clove and Malaria

Malaria in pregnancy (MIP) increases the risk of poor maternal and infant outcomes. To reduce these risks, WHO recommends insecticide-treated net (ITN) use, intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP), and prompt case management. However, uptake of these interventions remains sub-optimal in Madagascar. A scoping review was conducted to determine the breadth and depth of information available during 2010-2021 about Madagascar's MIP activities and to identify barriers and facilitators to MIP interventions uptake.. PubMed, Google Scholar, and USAID's files (Development Experience Catalog) were searched using the terms "Madagascar AND pregnancy AND malaria," and reports and materials from stakeholders were collected. Documents in English and French from 2010 to 2021 with data regarding MIP were included. Documents were systematically reviewed and summarized; results were captured in an Excel database.. Of 91 project reports, surveys and published articles, 23 (25%) fell within the stated time period and contained relevant data on MIP activities in Madagascar and were categorized accordingly: eight (35%) quality of care, including health facility readiness, provider knowledge and commodity availability; nine (39%) care-seeking behaviour; and, six (26%) prevention of MIP. Key barriers were identified: nine articles mentioned SP stockouts; seven found limitations of provider knowledge, attitudes, and behaviours (KAB) regarding MIP treatment and prevention; and, one reported limited supervision. MIP care seeking and prevention barriers and facilitators included women's KAB regarding MIP treatment and prevention, distance, wait times, poor service quality, cost, and/or unwelcoming providers. A 2015 survey of 52 health facilities revealed limited client access to antenatal care due to financial and geographic barriers; two 2018 surveys revealed similar findings. Self-treatment and care-seeking delays were reported even when distance was not a barrier.. Among the studies and reports on MIP in Madagascar, the scoping review frequently noted barriers that could be mitigated by reducing stockouts, improving provider knowledge and attitudes, refining MIP communication, and improving service access. There is a need for coordinated efforts to address the identified barriers is the key implication of the findings.

Topics: Antimalarials; Drug Combinations; Female; Humans; Madagascar; Malaria; Patient Acceptance of Health Care; Pregnancy; Pregnancy Complications, Parasitic; Prenatal Care; Pyrimethamine

Madagascar is cited as one of the most vulnerable countries to the effects of climate change, with significant impacts to the health of its population. In this study, the vulnerability of Madagascar's health sector to climate change was assessed and appropriate adaptation measures were identified. In order to assess climate risks, vulnerability and identify adaptation options, the Madagascar Ministry of Public Health as well as the National Meteorological and Hydrological Service worked in close collaboration with a team of local experts to conduct a literature review, field surveys, and analyses of current and future climate and health trends. Four climate-sensitive diseases of primary concern are described in the study: acute respiratory infections (ARI), diarrhea, malnutrition, and malaria. Baseline conditions of these four diseases from 2000 to 2014 show acute respiratory infections and diarrheal diseases are increasing in incidence; while incidence of malnutrition and malaria decreased over this period. To assess future impacts in Madagascar, this baseline information was used with climate projections for the two scenarios-RCP 4.5 and RCP 8.5-for the periods 2016⁻2035, 2036⁻2070 and 2071⁻2100. Future climate conditions are shown to exacerbate and increase the incidence of all four climate sensitive diseases. Further analysis of the exposure, sensitivity and adaptive capacity to the climate hazards suggests that the health sector in four regions of Madagascar is particularly vulnerable. The study recommends adaptation measures to improve the monitoring and early warning systems for climate sensitive diseases, as well as to reduce population vulnerability.

Topics: Acclimatization; Adaptation, Physiological; Climate Change; Diarrhea; Environmental Monitoring; Health Status Indicators; Humans; Incidence; Madagascar; Malaria; Malnutrition; Population Surveillance; Public Health Surveillance; Respiratory Tract Infections

Malaria epidemiology differs greatly in the geographically close islands of the southwestern Indian Ocean. In Madagascar and the Comoros Union malaria is still a major public health problem. In Mayotte indigenous transmission resumed in 1995 and is currently high in some communities. In the Mascarene Islands (Reunion and Mauritius), indigenous transmission has been eradicated (Reunion) or become rare (Mauritius). The Seychelles Islands are malaria-free since local conditions are unfavorable for Anopheles mosquitoes. The level of resistance to antimalarials also differs from one island to another. Resistance to chloroquine ranges from moderate in Madagascar to high in the Comoros Union. Health recommendations for travelers must be adapted to the epidemiological features on each island.

Topics: Animals; Anopheles; Antimalarials; Chloroquine; Comoros; Drug Resistance; Humans; Indian Ocean Islands; Madagascar; Malaria; Mauritius; Plasmodium falciparum; Reunion; Seychelles; Travel

The purpose of this article is to present data on malaria in the central highland plateaux of Madagascar and strategies to improve the national malaria control program. Use of rapid diagnosis strips, early home-based fever management with pre-packaged chloroquine treatment kits and proposed new therapeutic combination based on artemisinine are discussed for management of patients with high suspicion of malaria attack. Preventive measures including alternated targeted and full-house indoor spraying for vector control, use of insecticide-impregnated bednets, implementation of intermittent preventive treatment in risk groups, optimization of the epidemic early detection and warning system using the Lot Quality Assurance Sampling method for epidemiological investigation if the alert threshold is exceeded, and provision of rapid diagnosis strips are presented.

Topics: Humans; Madagascar; Malaria; Quality Assurance, Health Care; Sampling Studies

Schistosomiasis and malaria constitute major health problems in Madagascar. The main objectives of the national schistosomiasis control programme--launched in 1998--are to improve knowledge about the modes of transmission of the disease and conduct mass treatment in hyperendemic areas, so as to lower incidence rates. A Geographic Information System (GIS) was established aiming to conduct a series of remote sensing studies based on digital image processing and analysis from Landsat TM and panchromatic Spot. The importance of local environmental and geographic characteristics in the Ihosy region such as proximity to roads and water were assessed by spatial analysis in order to construct a predictive model of Schistosoma mansoni endemicity. Unstable transmission in the Central Highlands of Madagascar caused severe outbreaks of malaria in the 1980s. Attempts to prevent such events reoccurring have been highlighted in the national malaria control programme. Thanks to intense vector control measures introduced in the area over a five-year period, a marked decrease in incidence of malaria was observed. This region borders on the Highlands as well as southern areas, allowing for vector control evaluation. The GIS and remote sensing system were applied to analyse ricefield areas, where the main vector are Anopheles funestus. Rice-field surfaces were statistically linked with abundance of vectors evaluated by entomological parametres.

Topics: Animals; Disease Outbreaks; Disease Vectors; Endemic Diseases; Geography; Humans; Information Systems; Madagascar; Malaria; Meteorological Concepts; Schistosomiasis; Spacecraft

It is well known that 'in many instances the rice agrosystem perfectly fits the ecological requirements of pathogens or vectors' and in fact 'malaria, schistosomiasis and Japanese encephalitis are important vector-borne diseases associated with rice production in developing countries' (IRRI, 1987). In spite of these fears, rice cultivation has been on the increase in the African region in response to demographic and economic pressures. However, although rice fields provide suitable breeding places for Anopheles mosquitoes and rice cultivation leads to an increase in the biting rates, the species which are adapted to these sites are not the same in all parts of Africa. Several examples illustrate this phenomenon: An. funestus in the rice fields of Madagascar, An. pharoensis in saline water rice fields in the delta of the Senegal river, An. arabiensis in northern Cameroon and Burundi, An. gambiae Mopti form in the Kou Valley (Burkina Faso) and An. gambiae Savanna form in the rice fields of Kafine near Bouaké (Côte d'Ivoire). The vectorial capacities of these species are not the same and malaria inoculation rates are not necessarily increased in the riceland agroecosystem. The consequences for malaria of introducing rice cultivation depend on the situation before its introduction: it could be worsened in unstable malaria areas but not in stable malaria areas. Therefore, sound epidemiological and entomological knowledge are needed before causing any environmental modifications for agricultural purposes and there should be regular monitoring to avoid any outbreak.

Topics: Burkina Faso; Burundi; Cameroon; Cote d'Ivoire; Humans; Madagascar; Malaria; Oryza; Senegal

The Italian Development Cooperation (DGCS) support the health reform process in Developing Countries, with the aim to provide populations in greatest need with access to decentralized health services. DGCS acts in close coordination with the donor community, United Nations' system and the World Bank, in agreement with sector-wide approach (SWAP) for health sector development. Since malaria control in endemic countries is a relevant component of the health system, DGCS is actively involved in the struggle against malaria in sub-Saharan Africa, supporting control activities and research capability strengthening. The following African countries are presently receiving bilateral support for antimalaria activities: Burkina Faso, Centre de Lutte contre le Paludisme in Ouagadougou; Ethiopia, community-based malaria control in Tigray; Eritrea, malaria control at national level in the framework of the Public Health and Rehabilitation Programme for Eritrea (PHARPE) initiative; Madagascar, malaria surveillance at national level; Tanzania, feasibility study for the support to the national malaria control programme. Support is provided by technical/financial assistance involving Italian academic and research institutions. On the multilateral channel, DGCS has provided regular contribution for WHO's work in malaria control and participates to the WHO Roll Back Malaria initiative. A new commitment to malaria is the trilateral joint scientific endeavour USA-Italy-Burkina Faso for the development and field testing of a candidate vaccine suitable for African populations.

Topics: Adult; Burkina Faso; Child, Preschool; Eritrea; Ethiopia; Female; Humans; International Cooperation; Italy; Madagascar; Malaria; Male; Tanzania

The Highlands of Madagascar were malaria free until 1878, when a severe epidemic occurred, following the development of irrigated rice farming. Then, the disease became endemic. Between 1949 and 1962, malaria was "eradicated" on the Highlands by joint house spraying and chemoprophylaxis measures. The main vector An. funestus disappeared. In 1986-1988, a very severe epidemic with high lethality rate devastated the Highlands. It is now under control. Thanks to the data of a religious dispensary, we could follow the evolution of malaria on the Highlands from 1971 to 1995. The number of cases begin to grow in 1975 when the surveillance was neglected. A second step was observed in 1979, when chemoprophylaxis/chemotherapy centres were closed. Then, the increase of malaria became exponential up to 1988. At the time, the prevalence had became similar to that of 1948, before the eradication. The epidemic is not due to global warming because the temperature has been stable for the last 30 years. The malaria rise was due the cancellation of control measures. When control was reactivated, the epidemic ceased. In Swaziland, Zimbabwe and South Africa, malaria epidemics were also due to control failure. In Uganda Highlands, above 1500 m, malaria rise seems linked to the environmental changes, e.g. the cultures which replace papyrus swamp in the valley. But malaria did not overcame the altitude of 1900 which it had already reached in 1960. Rainfall should also be considered as a key factor in the epidemics. In the Sahel West Africa, temperature increased from 0.5 degree C to 01 degree C degree in the last 25 years, but rainfall decreased from 30%. As a result, one of the vector, Anopheles funestus disappeared and malaria prevalence dropped by 60 to 80%. It is not acceptable to predict the future evolution of malaria in taking in account only one parameter: the temperature. The whole factors involved in the epidemiology should be taken into account. The predictions based only on the temperature increase (global warming) can be totally wrong if the rainfall, for example, decreases.

Topics: Africa; Animals; Anopheles; Humans; Madagascar; Malaria; Mosquito Control

A strong malaria epidemic with a high mortality rate occurred on the Madagascar Highlands in 1986-88. Vector control and free access to antimalaria drugs controlled the disease. The authors have searched for the causes of the epidemic to propose a strategy avoiding such events. The Highlands on Madagascar were known as malaria free. In 1878 a very severe epidemic flooded all the country. Development of irrigated ricefields which house both An. arabiensis and An. funestus had created a new anthropic environment. Moreover manpower imported from malarious coastal areas for rice cultivation and also for building large temples, could have brought P. falciparum. After several outbreaks the disease became endemic up to 1949. In 1949 a malaria eradication programme based on DDT spraying and drug chemoprophylaxis and chemotherapy was launched. By 1960 malaria was eliminated and DDT spraying cancelled. Only 3 foci were kept under surveillance with irregular spraying until 1975. The prophylaxis and treatment centres ("centres de nivaquinisation") were kept open up to 1979. The catholic dispensary of Analaroa, 100 km N.E. of Tananarive, opened in 1971 and worked without interruption up to now. The malaria diagnosis has always been controlled by microscopy. Its registers are probably the more reliable source of information on malaria in the area. They show that malaria was already present on the Highlands in 1971 but at a low prevalence; in 1980 when the "centres de nivaquinisation" were closed the number of cases increased by three times the progressive increase of the number of cases became exponential from 1986 to 1988 which was the peak of the epidemic; malaria remained at a high level until the end of 1993; yearly DDT spraying since 1993 have decreased the number of malaria cases among the dispensary attendants by 90%. The epidemic peak of 1988 was well documented by the Pasteur Institute of Madagascar around Tananarive. Before the epidemic started it was observed a come back of An. funestus which had been previously eliminated of most of the villages by DDT spraying. More than an epidemic the malaria increase in 1988 was a reconquest by malaria of the land from which it had been eliminated in the years 1950. This episode became dramatic because the lack of immunity of the population and the shortage of medicaments. The global warming which was advocated to explain the epidemic has no responsibility because the temperature on the Madagascar Highlands has not chan

Topics: DDT; History, 18th Century; History, 19th Century; History, 20th Century; Humans; Madagascar; Malaria; Mosquito Control

Madagascar is considered as a sub-region of the Afrotropical geographical Region in spite of the high endemicity of 95% of the invertebrates. Nevertheless the three malaria vectors An. gambiae s.s., An. arabiensis and An. funestus are quite similar to those of the continental Africa. This support the hypothesis of their recent introduction. Plasmodium falciparum is the dominant parasite but the prevalence of P. vivax is not negligible. It is linked to the Asian component of the human population. P. malariae and P. ovale are of minor importance. The main epidemiological "facies" of Africa are found in Madagascar. The equatorial facies on the East Coast is characterized by a high transmission all year long. In the tropical facies on the West Coast transmission is seasonal (7 months at least). In both areas, malaria is stable and the inhabitants acquire a high immunity before the age of ten; most of the severe cases touch children below 10. The three vectors can be found but An. gambiae s.s. is dominant. In the exophilic southern facies the transmission is seasonal (two to four months). The only vector is An. arabiensis. Malaria is unstable and severe epidemics occur during the years of high rainfall. All age groups are vulnerable because the population is not immune in the Plateaux facies above 1,000 m., malaria is unstable. Severe epidemics occurred in 1987-1988. The vectors are An. Arabiensis and An. funestus. The occurrence of P. falciparum on the Plateaux seems linked to the development of irrigation of rice farming in the XIXth century. Most of the anopheles breeding places on the Plateaux are dependent on rice cultivation. Urban development has brought the inhabitants of the suburbs in close contact with rice fields. Despite the high number of anopheline bites the number of malaria cases remains by far lower than in the neighbouring rural areas. Regional migrations inside the island bring non-immune populations, from the south and the plateaux, in highly malarious areas of the coast, where the migrants are exposed to high risk. In spite of 40 years of uncontrolled use, chloroquine can still cure most, if not all, of malaria cases. Control measures appropriated to the different areas of Madagascar are discussed.

Topics: Agriculture; Animals; Anopheles; Chloroquine; Emigration and Immigration; Humans; Insect Vectors; Madagascar; Malaria; Malaria, Falciparum; Malaria, Vivax; Oryza; Plasmodium malariae; Population Surveillance; Prevalence; Risk Factors; Seasons; Severity of Illness Index; Urbanization; Water

Two-hundred thirty-nine Madagascan medicinal plants have been either retrieved from computerized ethnobotany information or identified in our own ethnomedicine work as having antimalarial properties. Such a high rate percent of plants compared to those used empirically to treat other diseases reflects the importance and the complication of this major tropical disease in Madagascar.

Topics: Antimalarials; Humans; Madagascar; Malaria; Plants, Medicinal

Topics: Animals; Chloroquine; Drug Resistance; Humans; Madagascar; Malaria; Plasmodium falciparum

Malaria remains a leading cause of morbidity and mortality worldwide, with progress in malaria control stalling in recent years. Proactive community case management (pro-CCM) has been shown to increase access to diagnosis and treatment and reduce malaria burden. However, lack of experimental evidence may hinder the wider adoption of this intervention. We conducted a cluster randomized community intervention trial to assess the efficacy of pro-CCM at decreasing malaria prevalence in rural endemic areas of Madagascar.. Twenty-two fokontany (smallest administrative unit) of the Mananjary district in southeast Madagascar were selected and randomized 1:1 to pro-CCM (intervention) or conventional integrated community case management (iCCM). Residents of all ages in the intervention arm were visited by a community health worker every 2 weeks from March to October 2017 and screened for fever; those with fever were tested by a rapid diagnostic test (RDT) and treated if positive. Malaria prevalence was assessed using RDTs on all consenting study area residents prior to and following the intervention. Hemoglobin was measured among women of reproductive age. Intervention impact was assessed via difference-in-differences analyses using logistic regressions in generalized estimating equations.. A total of 27,087 and 20,475 individuals participated at baseline and endline, respectively. Malaria prevalence decreased from 8.0 to 5.4% in the intervention arm for individuals of all ages and from 6.8 to 5.7% in the control arm. Pro-CCM was associated with a significant reduction in the odds of malaria positivity in children less than 15 years (OR = 0.59; 95% CI [0.38-0.91]), but not in older age groups. There was no impact on anemia among women of reproductive age.. This trial suggests that pro-CCM approaches could help reduce malaria burden in rural endemic areas of low- and middle-income countries, but their impact may be limited to younger age groups with the highest malaria burden.. NCT05223933. Registered on February 4, 2022.

Topics: Aged; Case Management; Child; Community Health Workers; Female; Humans; Infant, Newborn; Madagascar; Malaria; Prevalence

Malaria infections are the leading cause of death for children in Madagascar. Insecticide-treated bednets offer effective prevention, but it is unclear how well free bednet distribution programs reach young children.. We conducted a secondary analysis of a free bednet distribution program in Madagascar from 2007-2008. Interviews were performed at baseline and 6 months. Principal components analysis was used to construct a wealth and malaria knowledge index. Coverage efficiency was calculated as coverage of children per bednet owned. Univariable and multivariable regressions were used to determine predictors of bednet use.. Bednet use, among the 560 households in the study, increased from 6 to 91% after 6 months. Coverage efficiency increased from 1.29 to 1.56 children covered per bednet owned. In multivariable analysis, having a child under 5 years of age was the only variable associated with bednet use (OR 9.10; p=0.001), yielding a 99% likelihood of using a bednet (95% CI 96.4 to 99.9%) versus 82% (95% CI 72.2 to 88.4%) in households without young children.. This free bednet distribution program achieved high levels of adherence after 6 months. Household presence of children was associated with bednet use, but not household income or education, suggesting that distribution to priority groups may help overcome traditional barriers to adoption in some settings.

Topics: Adult; Child; Child, Preschool; Family Characteristics; Female; Humans; Infant; Insecticide-Treated Bednets; Insecticides; Interviews as Topic; Madagascar; Malaria; Male; Odds Ratio; Outcome Assessment, Health Care; Pregnancy; Principal Component Analysis; Program Evaluation; Public Health; Regression Analysis; Rural Population; Socioeconomic Factors; Surveys and Questionnaires

We report the results of clinical studies carried out at six sites in Madagascar, between January and October 2006. The aims were (i) to update our knowledge of the burden of Plasmodium malariae infection and (ii) to assess the therapeutic efficacy of chloroquine for uncomplicated quartan malaria. Our findings confirm that P. malariae is the third leading cause of malaria, accounting for 1.1% of all malarial infections. They also demonstrate that chloroquine-currently recommended for the home management of presumed malaria in children under the age of five years and commonly used by adults-remains highly effective in patients with uncomplicated P. malariae infection.

Topics: Adolescent; Adult; Animals; Antimalarials; Child; Child, Preschool; Chloroquine; Female; Humans; Infant; Madagascar; Malaria; Male; Parasitemia; Plasmodium malariae; Prevalence; Time Factors; Treatment Outcome

Topics: Altitude; Animals; Anopheles; Household Articles; Humans; Insecticides; Interior Design and Furnishings; Madagascar; Malaria; Morbidity; Mosquito Control; Nitriles; Population Surveillance; Pyrethrins; Seasons

The therapeutic effects and side effects of mefloquine in falciparum malaria were investigated in an open prospective trial involving 20 patients. None of them had a history of neurologic or psychiatric disorders. Mefloquine was given in a total dose of 1500 mg base. The cure rate was 100%, fever and parasitemia subsided within 3 days. Side effects were vomitus and nausea in 25% of the patients. No neurological or psychiatric disorders were observed. Mefloquine was shown to be a safe therapeutic agent in the dosage used. However, regular follow-up examinations should be done in short intervals because of the possibility of late neuropsychiatric side effects; the patients and their relatives should be informed about this fact.

Topics: Adolescent; Adult; Africa, Western; Animals; Female; Germany; Humans; Madagascar; Malaria; Male; Mefloquine; Mental Disorders; Nausea; Nervous System Diseases; Plasmodium falciparum; Prospective Studies; Travel; Uganda; Vomiting

Intermittent preventive treatment of malaria in pregnancy (IPTp) with sulfadoxine-pyrimethamine is recommended at each antenatal care clinic visit in high-moderate transmission areas. However, its coverage remains unacceptably low in many countries. Community health workers can effectively deliver malaria preventive interventions. The aim of this study was to assess the effect of community delivery of IPTp (C-IPTp) on antenatal care and IPTp coverage.. A community-based IPTp administration approach was implemented in four sub-Saharan countries: the Democratic Republic of the Congo (DR Congo), Madagascar, Mozambique, and Nigeria. A quasi-experimental before and after evaluation by cluster sampling was designed where C-IPTp was implemented in selected country areas in different phases. Baseline (before C-IPTp implementation), midline, and endline household surveys were carried out to assess IPTp intake in pregnant women in 2018, 2019, and 2021. Eligible participants of the household survey were women of reproductive age (13-50 years old, depending on the country) that had a pregnancy that ended (any pregnancy regardless of pregnancy outcome) in the 6 months before the interview. For the first baseline surveys, the target population was women who had a pregnancy that ended in the 12 months before the interview. The primary outcome from the household surveys was the proportion of women who reported having received at least three doses of IPTp during pregnancy. The trial is registered at ClinicalTrials.gov, NCT03600844.. A total of 32 household surveys were conducted between March 15, and Oct 30, 2018, and data from 18 215 interviewed women were analysed. The coverage of at least three doses of IPTp (IPTp3+) increased after the first year of C-IPTp implementation in all project areas in DR Congo (from 22·5% [170/755] to 31·8% [507/1596]), Madagascar (from 17·7% [101/572] to 40·8% [573/1404]), and Nigeria (from 12·7% [130/1027] to 35·2% [423/1203]), with increases between 145·6% (Madagascar) and 506·6% (Nigeria). IPTp3+ coverage increased between baseline and endline in all districts, except for Murrupula (Mozambique) and ranged between 9·6% and 533·6%. This pattern was similar in DR Congo, Madagascar, and Nigeria, and in Mozambique, the increase was lower than the other countries. Antenatal care attendance did not change or increased lightly in all study countries.. C-IPTp was associated with an increase in IPTp uptake without reducing antenatal care attendance. The strategy might be considered for malaria control in pregnancy.. UNITAID [2017-13-TIPTOP].

Topics: Adolescent; Adult; Antimalarials; Democratic Republic of the Congo; Drug Combinations; Female; Humans; Madagascar; Malaria; Male; Middle Aged; Mozambique; Nigeria; Pregnancy; Pregnancy Complications, Parasitic; Pyrimethamine; Sulfadoxine; Young Adult

Historically, vector control, including entomological monitoring, has been a field dominated by men. Each year, the U.S. President's Malaria Initiative (PMI) VectorLink project hires 50,000 to 70,000 seasonal workers across the countries in which it works to implement vector control activities, creating an economic opportunity for both men and women. Remaining barriers to women's employment in vector control include social and cultural norms regarding acceptability of formal employment for women, perceptions that women are not fit to serve as spray operators, and a historical context of male-dominated fields such as entomology.. We use PMI VectorLink project data from Madagascar, Rwanda, and Zambia for 2019-2021 and key informant interviews with project staff in these countries to examine levels of female employment, effectiveness and efficiency of female versus male malaria spray operators, and strategies to expand the role of women in vector control.. The percentage of female seasonal employees ranges from 25% in Madagascar to 32% in Rwanda and 45% in Zambia. The percentage of women in leadership positions ranges from 32% in Madagascar and Rwanda to 38% in Zambia. Men and women are equally effective and efficient as spray operators. Best practices for recruiting and retaining women in vector control include engaging community leaders in recruitment, implementing affirmative action hiring policies, mentoring women to progress to leadership positions, and ensuring equitable, safe, and attractive workplaces.. As vector control programs transition away from donor funding and are increasingly government led, sustaining gains in female empowerment is critical. Country programs should work closely with national, regional, district, and local leaders to demonstrate the importance of hiring women in vector control-including leadership positions-and the impact on female economic empowerment, community well-being, and success of vector control programs.

Topics: Employment; Female; Humans; Madagascar; Malaria; Male; Rwanda; Zambia

Indoor residual spraying (IRS) and insecticide-treated bed nets (ITNs) are cornerstone malaria prevention methods in Madagascar. This retrospective observational study uses routine data to evaluate the impacts of IRS overall, sustained IRS exposure over multiple years and level of spray coverage (structures sprayed/found) in nine districts where non-pyrethroid IRS was deployed to complement standard pyrethroid ITNs from 2017 to 2020.. Multilevel negative-binomial generalised linear models were fit to estimate the effects of IRS exposure overall, consecutive years of IRS exposure and spray coverage level on monthly all-ages population-adjusted malaria cases confirmed by rapid diagnostic test at the health facility level. The study period extended from July 2016 to June 2021. Facilities with missing data and non-geolocated communes were excluded. Facilities in IRS districts were matched with control facilities by propensity score analysis. Models were controlled for ITN survivorship, mass drug administration coverage, precipitation, enhanced vegetation index, seasonal effects and district. Predicted cases under a counterfactual. Exposure to IRS overall reduced case incidence by an estimated 30.3% from 165.8 cases per 1000 population (95% CI=139.7 to 196.7) under a counterfactual no IRS scenario, to 114.3 (95% CI=96.5 to 135.3) over 12 months post-IRS campaign in nine districts. A third year of IRS reduced malaria cases 30.9% more than a first year (incidence rate ratio (IRR)=0.578, 95% CI=0.578 to 0.825, p<0.001) and 26.7% more than a second year (IRR=0.733, 95% CI=0.611 to 0.878, p=0.001). There was no significant difference between the first and second year (p>0.05). Coverage of 86%-90% was associated with a 19.7% reduction in incidence (IRR=0.803, 95% CI=0.690 to 0.934, p=0.005) compared with coverage ≤85%, although these results were not robust to sensitivity analysis.. This study demonstrates that non-pyrethroid IRS appears to substantially reduce malaria incidence in Madagascar and that sustained implementation of IRS over three years confers additional benefits.

Topics: Humans; Insecticides; Madagascar; Malaria; Mosquito Control; Retrospective Studies

Malaria in pregnancy is a major driver of maternal and infant mortality in sub-Saharan Africa. The WHO recommends the administration of intermittent preventive treatment with sulfadoxine pyrimethamine (IPTp-SP) at antenatal care (ANC) visits. Despite being a highly cost-effective strategy, IPTp-SP coverage and uptake remains low. A pilot project was conducted to assess the cost-effectiveness (CE) of community-based delivery of IPTp (C-IPTp) in addition to ANC delivery to increase IPTp uptake in the Democratic Republic of Congo (DRC), Madagascar (MDG), Mozambique (MOZ) and Nigeria (NGA).. Costs and CE estimates of C-IPTp were calculated according to two scenarios: (1) costs in 'programmatic mode' (ie, costs if C-IPTp was to be implemented by national health systems) and (2) costs from the pilot project. The effectiveness of C-IPTp was obtained through estimates of the averted disability-adjusted life-years (DALYs) associated with maternal clinical malaria and anaemia, low birth weight and neonatal mortality.. Net incremental costs of C-IPTp ranged between US$6138-US$47 177 (DRC), US$5552-US$31 552 (MDG), US$10 202-US$53 221 (MOZ) and US$667-US$28 645 (NGA) per 1000 pregnant women, under scenarios (1) and (2), respectively. Incremental cost-effectiveness ratios (ICERs) ranged between US$15-US$119 in DRC, US$9-US$53 in MDG, US$104-US$543 in MOZ and US$2-US$66 in NGA per DALY averted, under scenarios (1) and (2), respectively. ICERs fall below the WHO recommended CE threshold based on the gross domestic product per capita.. Findings suggest that C-IPTp is a highly cost-effective intervention. Results can inform policy decisions on adopting and optimising effective interventions for preventing malaria in pregnancy.

Topics: Cost-Benefit Analysis; Delivery of Health Care; Democratic Republic of the Congo; Female; Humans; Infant; Infant, Newborn; Madagascar; Malaria; Mozambique; Nigeria; Pilot Projects; Pregnancy

Data on population health are vital to evidence-based decision making but are rarely adequately localized or updated in continuous time. They also suffer from low ascertainment rates, particularly in rural areas where barriers to healthcare can cause infrequent touch points with the health system. Here, we demonstrate a novel statistical method to estimate the incidence of endemic diseases at the community level from passive surveillance data collected at primary health centers. The zero-corrected, gravity-model (ZERO-G) estimator explicitly models sampling intensity as a function of health facility characteristics and statistically accounts for extremely low rates of ascertainment. The result is a standardized, real-time estimate of disease incidence at a spatial resolution nearly ten times finer than typically reported by facility-based passive surveillance systems. We assessed the robustness of this method by applying it to a case study of field-collected malaria incidence rates from a rural health district in southeastern Madagascar. The ZERO-G estimator decreased geographic and financial bias in the dataset by over 90% and doubled the agreement rate between spatial patterns in malaria incidence and incidence estimates derived from prevalence surveys. The ZERO-G estimator is a promising method for adjusting passive surveillance data of common, endemic diseases, increasing the availability of continuously updated, high quality surveillance datasets at the community scale.

Topics: Endemic Diseases; Humans; Incidence; Madagascar; Malaria; Patient Acceptance of Health Care

Histidine-rich protein 2 (HRP2)-based rapid diagnostic tests detect Plasmodium falciparum malaria and are used throughout sub-Saharan Africa. However, deletions in the pfhrp2 and related pfhrp3 (pfhrp2/3) genes threaten use of these tests. Therapeutic efficacy studies (TESs) enroll persons with symptomatic P. falciparum infection. We screened TES samples collected during 2016-2018 in Ethiopia, Kenya, Rwanda, and Madagascar for HRP2/3, pan-Plasmodium lactate dehydrogenase, and pan-Plasmodium aldolase antigen levels and selected samples with low levels of HRP2/3 for pfhrp2/3 genotyping. We observed deletion of pfhrp3 in samples from all countries except Kenya. Single-gene deletions in pfhrp2 were observed in 1.4% (95% CI 0.2%-4.8%) of Ethiopia samples and in 0.6% (95% CI 0.2%-1.6%) of Madagascar samples, and dual pfhrp2/3 deletions were noted in 2.0% (95% CI 0.4%-5.9%) of Ethiopia samples. Although this study was not powered for precise prevalence estimates, evaluating TES samples revealed a low prevalence of pfhrp2/3 deletions in most sites.

Topics: Antigens, Protozoan; Diagnostic Tests, Routine; Ethiopia; Gene Deletion; Humans; Kenya; Madagascar; Malaria; Malaria, Falciparum; Plasmodium falciparum; Protozoan Proteins; Rwanda

Prompt diagnosis and treatment of malaria contributes to reduced morbidity, particularly among children and pregnant women; however, in Madagascar, care-seeking for febrile illness is often delayed. To describe factors influencing decisions for prompt care-seeking among caregivers of children aged < 15 years and pregnant women, a mixed-methods assessment was conducted with providers (HP), community health volunteers (CHV) and community members.. One health district from each of eight malaria-endemic zones of Madagascar were purposefully selected based on reported higher malaria transmission. Within districts, one urban and one rural community were randomly selected for participation. In-depth interviews (IDI) and focus group discussions (FGD) were conducted with caregivers, pregnant women, CHVs and HPs in these 16 communities to describe practices and, for HPs, system characteristics that support or inhibit care-seeking. Knowledge tests on malaria case management guidelines were administered to HPs, and logistics management systems were reviewed.. Participants from eight rural and eight urban communities included 31 HPs from 10 public and 8 private Health Facilities (HF), five CHVs, 102 caregivers and 90 pregnant women. All participants in FGDs and IDIs reported that care-seeking for fever is frequently delayed until the ill person does not respond to home treatment or symptoms become more severe. Key care-seeking determinants for caregivers and pregnant women included cost, travel time and distance, and perception that the quality of care in HFs was poor. HPs felt that lack of commodities and heavy workloads hindered their ability to provide quality malaria care services. Malaria commodities were generally more available in public versus private HFs. CHVs were generally not consulted for malaria care and had limited commodities.. Reducing cost and travel time to care and improving the quality of care may increase prompt care-seeking among vulnerable populations experiencing febrile illness. For patients, perceptions and quality of care could be improved with more reliable supplies, extended HF operating hours and staffing, supportive demeanors of HPs and seeking care with CHVs. For providers, malaria services could be improved by increasing the reliability of supply chains and providing additional staffing. CHVs may be an under-utilized resource for sick children.

Topics: Caregivers; Child; Female; Humans; Madagascar; Malaria; Patient Acceptance of Health Care; Pregnancy; Pregnant Women; Reproducibility of Results

Intermittent preventive treatment in pregnancy with sulphadoxine pyrimethamine (IPTp) is a key malaria prevention strategy in sub-Saharan African countries. We conducted an anthropological study as part of a project aiming to evaluate a community-based approach to the delivery of IPTp (C-IPTp) through community health workers (CHWs) in four countries (the Democratic Republic of Congo, Madagascar, Mozambique and Nigeria), to understand the social context in order to identify key factors that could influence C-IPTp acceptability.. A total of 796 in-depth interviews and 265 focus group discussions were undertaken between 2018 and 2021 in the four countries with pregnant women, women of reproductive age, traditional and facility-based healthcare providers, community leaders, and relatives of pregnant women. These were combined with direct observations (388) including both community-based and facility-based IPTp delivery. Grounded theory guided the overall study design and data collection, and data were analysed following a combination of content and thematic analysis.. A series of key factors were found to influence acceptability, delivery and uptake of C-IPTp in project countries. Cross-cutting findings include the alignment of the strategy with existing social norms surrounding pregnancy and maternal health-seeking practices, the active involvement of influential and trusted actors in implementation activities, existing and sustained trust in CHWs, the influence of husbands and other relatives in pregnant women's care-seeking decision-making, the working conditions of CHWs, pregnant women's perceptions of SP for IPTp and persistent barriers to facility-based antenatal care access.. The findings provide evidence on the reported acceptability of C-IPTp among a wide range of actors, as well as the barriers and facilitators for delivery and uptake of the intervention. Overall, C-IPTp was accepted by the targeted communities, supporting the public health value of community-based interventions, although the barriers identified should be examined if large-scale implementation of the intervention is considered.

Topics: Antimalarials; Democratic Republic of the Congo; Female; Humans; Madagascar; Malaria; Mozambique; Nigeria; Pregnancy

Integrated community case management of malaria, pneumonia, and diarrhoea can reduce mortality in children under five years (CU5) in resource-poor countries. There is growing interest in expanding malaria community case management (mCCM) to older individuals, but limited empirical evidence exists to guide this expansion. As part of a two-year cluster-randomized trial of mCCM expansion to all ages in southeastern Madagascar, a cross-sectional survey was conducted to assess baseline malaria prevalence and healthcare-seeking behaviours.. Two enumeration areas (EAs) were randomly chosen from each catchment area of the 30 health facilities (HFs) in Farafangana district designated for the mCCM age expansion trial; 28 households were randomly selected from each EA for the survey. All household members were asked about recent illness and care-seeking, and malaria prevalence was assessed by rapid diagnostic test (RDT) among children < 15 years of age. Weighted population estimates and Rao-Scott chi-squared tests were used to examine illness, care-seeking, malaria case management, and malaria prevalence patterns.. Illness in the two weeks prior to the survey was reported by 459 (6.7%) of 8050 respondents in 334 of 1458 households surveyed. Most individuals noting illness (375/459; 82.3%) reported fever. Of those reporting fever, 28.7% (112/375) sought care; this did not vary by participant age (p = 0.66). Most participants seeking care for fever visited public HFs (48/112, 46.8%), or community healthcare volunteers (CHVs) (40/112, 31.0%). Of those presenting with fever at HFs or to CHVs, 87.0% and 71.0%, respectively, reported being tested for malaria. RDT positivity among 3,316 tested children < 15 years was 25.4% (CI: 21.5-29.4%) and increased with age: 16.9% in CU5 versus 31.8% in 5-14-year-olds (p < 0.0001). Among RDT-positive individuals, 28.4% of CU5 and 18.5% of 5-14-year-olds reported fever in the two weeks prior to survey (p = 0.044).. The higher prevalence of malaria among older individuals coupled with high rates of malaria testing for those who sought care at CHVs suggest that expanding mCCM to older individuals may substantially increase the number of infected individuals with improved access to care, which could have additional favorable effects on malaria transmission.

Topics: Adolescent; Case Management; Child; Child, Preschool; Cross-Sectional Studies; Female; Humans; Infant; Madagascar; Malaria; Male; Patient Acceptance of Health Care; Prevalence; Rural Population

In low-malaria-transmission areas of Madagascar, annual parasite incidence (API) from routine data has been used to target indoor residual spraying at subdistrict commune level. To assess validity of this approach, we conducted school-based serological surveys and health facility (HF) data quality assessments in 7 districts to compare API to gold-standard commune-level serological measures.. At 2 primary schools in each of 93 communes, 60 students were randomly selected with parents and teachers. Capillary blood was drawn for rapid diagnostic tests (RDTs) and serology. Multiplex bead-based immunoassays to detect antibodies to 5 Plasmodium falciparum antigens were conducted, and finite mixture models used to characterize seronegative and seropositive populations. Reversible catalytic models generated commune-level annual seroconversion rates (SCRs). HF register data were abstracted to assess completeness and accuracy.. RDT positivity from 12 770 samples was 0.5%. Seroprevalence to tested antigens ranged from 17.9% (MSP-1) to 59.7% (PF13). Median commune-level SCR was 0.0108 (range, 0.001-0.075). Compared to SCRs, API identified 71% (95% confidence interval, 51%-87%) of the 30% highest-transmission communes; sensitivity declined at lower levels. Routine data accuracy did not substantially affect API performance.. API performs reasonably well at identifying higher-transmission communes but sensitivity declined at lower transmission levels.

Topics: Health Facilities; Humans; Madagascar; Malaria; Schools; Seroepidemiologic Studies

Intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) is a key malaria prevention strategy in areas with moderate to high transmission. As part of the TIPTOP (Transforming IPT for Optimal Pregnancy) project, baseline information about IPTp coverage was collected in eight districts from four sub-Saharan countries: Democratic Republic of Congo (DRC), Madagascar, Mozambique and Nigeria.. Cross-sectional household surveys were conducted using a multistage cluster sampling design to estimate the coverage of IPTp and antenatal care attendance. Eligible participants were women of reproductive age who had ended a pregnancy in the 12 months preceding the interview and who had resided in the selected household during at least the past 4 months of pregnancy. Coverage was calculated using percentages and 95% confidence intervals.. A total of 3911 women were interviewed from March to October 2018. Coverage of at least three doses of IPTp (IPTp3+) was 22% and 24% in DRC project districts; 23% and 12% in Madagascar districts; 11% and 16% in Nigeria local government areas; and 63% and 34% in Mozambique districts. In DRC, Madagascar and Nigeria, more than two-thirds of women attending at least four antenatal care visits during pregnancy received less than three doses of IPTp.. The IPTp3+ uptake in the survey districts was far from the universal coverage. However, one of the study districts in Mozambique showed a much higher coverage of IPTp3+ than the other areas, which was also higher than the 2018 average national coverage of 41%. The reasons for the high IPTp3+ coverage in this Mozambican district are unclear and require further study.

Topics: Antimalarials; Cross-Sectional Studies; Drug Combinations; Female; Humans; Infant; Madagascar; Malaria; Mozambique; Nigeria; Pregnancy; Pregnancy Complications, Parasitic; Prenatal Care; Pyrimethamine; Sulfadoxine

In sub-Saharan Africa (SSA), millions of pregnant women are exposed to malaria infection. The cornerstone of the WHO strategy to prevent malaria in pregnancy in moderate to high-transmission areas is the administration of intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine at each scheduled antenatal care (ANC) visit. However, overall coverage remains low. 'Transforming IPT for Optimal Pregnancy' (TIPTOP) project aims at delivering IPTp at the community level (C-IPTp) to complement ANC provision with the goal of increasing IPTp coverage and improving maternal and infant's health. This protocol describes the approach to measure the effect of this strategy through household surveys (HHS) in four SSA countries: Democratic Republic of Congo (DRC), Madagascar, Mozambique and Nigeria.. A quasi-experimental evaluation has been designed. Delivery of C-IPTp will start first in one area per country, and later it will be extended to two more areas per country. HHS will be carried out before C-IPTp implementation in all study sites, at midterm in initial implementation areas, and after the implementation in all project areas. A multistage cluster sampling method will be followed for the selection of participants. Women of reproductive age who had a pregnancy that ended in the 6 or 12 months prior to the interview, depending on the survey, will be invited to participate by responding to a questionnaire. The main indicators will be coverage of three or more doses of IPTp and attendance to at least four ANC visits. A difference-in-difference analysis will be performed to evaluate the effectiveness of C-IPTp.. The project has been reviewed by the ethics committees of WHO, Hospital Clinic of Barcelona and all project country boards. Project results will be disseminated to in-country stakeholders and at regional and international meetings. TIPTOP project aims to develop and disseminate global recommendations for C-IPTp delivery.. NCT03600844; Pre-results.

Topics: Antimalarials; Drug Combinations; Female; Humans; Infant; Madagascar; Malaria; Mozambique; Nigeria; Pregnancy

Although it is accepted that long-lasting insecticidal net (LLIN) use is an effective means to prevent malaria, children aged 5 to 15 years do not appear to be sufficiently protected in Madagascar; the malaria prevalence is highest in this age group. The purpose of this research is to summarize recent qualitative studies describing LLIN use among the Malagasy people with a focus on children aged 5-15 years.. Qualitative data from three studies on malaria conducted between 2012 and 2016 in 10 districts of Madagascar were analysed. These studies cover all malaria epidemiological profiles and 10 of the 18 existing ethnic groups in Madagascar. A thematic analysis was conducted on the collected data from semi-structured interviews, direct observation data, and informal interviews.. A total of 192 semi-structured interviews were conducted. LLINs are generally perceived positively because they protect the health and well-being of users. However, regional representations of mosquito nets may contribute to LLIN lower use by children over 5 years of age including the association between married status and LLIN use, which leads to the refusal of unmarried young men to sleep under LLINs; the custom of covering the dead with a mosquito net, which leads to fear of LLIN use; and taboos governing sleeping spaces for siblings of opposite sexes, which leads to LLIN shortages in households. Children under 5 years of age are known to be the most vulnerable age group for acquiring malaria and, therefore, are prioritized for LLIN use when there are limited supplies in households. In contrast, children over 5 years of age, who are perceived to be at less risk for malaria, often sleep without LLINs.. Perceptions, social practices and regional beliefs regarding LLINs and vulnerability to malaria contribute to the nonuse of LLINs among children over 5 years of age in Madagascar. Modifying LLIN policies to account for these factors may increase LLIN use in this age group and reduce disease burden.

Topics: Adolescent; Child; Child, Preschool; Female; Humans; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Mosquito Control

Acute Kidney Injury (AKI) is one of the criteria for severe malaria with a varied incidence. Our objectives are to determine the prevalence of malaria-associated AKI and to report the characteristics of patients with the evolution of cases.. This is a 5-year retrospective descriptive study from January 1, 2015 to December 31, 2019 in the Infectious Diseases department of the University Hospital Center of Befelatanana Antananarivo. Among 379 patients diagnosed, 103 patients (27,18%) with associated AKI were included. We used the criteria of Kidney Disease Improving Global Outcomes group to define AKI.. The prevalence of AKI was 27.18%. The mean age of patients was 34.92 years and the sex-ratio was 3.68. Plasmodium falciparum was the causative agent in 98.06% of cases followed by Plasmodium vivax. Diuresis was preserved in 69.86% of cases. Jaundice was the main sign of severity associated (49.51%). The mean creatinine level was 466.93μmol/L. The evolution was favorable under antimalarial drug and rehydration. Dialysis was required in 25.24% of cases. Thirteen patients had died, a rate of 12.62%, of which 8 patients (61.54%) had dialysis criteria but had not been purged for economic reasons.. AKI is a frequent complication of malaria. It is responsible for significant mortality despite improved care in the fight against malaria.

Topics: Acute Kidney Injury; Adult; Humans; Incidence; Madagascar; Malaria; Retrospective Studies

Large-scale variation in ecological parameters across Madagascar is hypothesized to drive varying spatial patterns of malaria infection. However, to date, few studies of parasite prevalence with resolution at finer, sub-regional spatial scales are available. As a result, there is a poor understanding of how Madagascar's diverse local ecologies link with variation in the distribution of infections at the community and household level. Efforts to preserve Madagascar's ecological diversity often focus on improving livelihoods in rural communities near remaining forested areas but are limited by a lack of data on their infectious disease burden.. To investigate spatial variation in malaria prevalence at the sub-regional scale in Madagascar, we sampled 1476 households (7117 total individuals, all ages) from 31 rural communities divided among five ecologically distinct regions. The sampled regions range from tropical rainforest to semi-arid, spiny forest and include communities near protected areas including the Masoala, Makira, and Mikea forests. Malaria prevalence was estimated by rapid diagnostic test (RDT) cross-sectional surveys performed during malaria transmission seasons over 2013-2017.. Indicative of localized hotspots, malaria prevalence varied more than 10-fold between nearby (< 50 km) communities in some cases. Prevalence was highest on average in the west coast region (Morombe district, average community prevalence 29.4%), situated near protected dry deciduous forest habitat. At the household level, communities in southeast Madagascar (Mananjary district) were observed with over 50% of households containing multiple infected individuals at the time of sampling. From simulations accounting for variation in household size and prevalence at the community level, we observed a significant excess of households with multiple infections in rural communities in southwest and southeast Madagascar, suggesting variation in risk within communities.. Our data suggest that the malaria infection burden experienced by rural communities in Madagascar varies greatly at smaller spatial scales (i.e., at the community and household level) and that the southeast and west coast ecological regions warrant further attention from disease control efforts. Conservation and development efforts in these regions may benefit from consideration of the high, and variable, malaria prevalences among communities in these areas.

Topics: Cross-Sectional Studies; Humans; Madagascar; Malaria; Prevalence; Rural Population

Topics: Humans; Madagascar; Malaria; Surveys and Questionnaires

Many malaria-endemic areas experience seasonal fluctuations in case incidence as Anopheles mosquito and Plasmodium parasite life cycles respond to changing environmental conditions. Identifying location-specific seasonality characteristics is useful for planning interventions. While most existing maps of malaria seasonality use fixed thresholds of rainfall, temperature, and/or vegetation indices to identify suitable transmission months, we construct a statistical modelling framework for characterising the seasonal patterns derived directly from monthly health facility data.. With data from 2669 of the 3247 health facilities in Madagascar, a spatiotemporal regression model was used to estimate seasonal patterns across the island. In the absence of catchment population estimates or the ability to aggregate to the district level, this focused on the monthly proportions of total annual cases by health facility level. The model was informed by dynamic environmental covariates known to directly influence seasonal malaria trends. To identify operationally relevant characteristics such as the transmission start months and associated uncertainty measures, an algorithm was developed and applied to model realisations. A seasonality index was used to incorporate burden information from household prevalence surveys and summarise 'how seasonal' locations are relative to their surroundings.. Positive associations were detected between monthly case proportions and temporally lagged covariates of rainfall and temperature suitability. Consistent with the existing literature, model estimates indicate that while most parts of Madagascar experience peaks in malaria transmission near March-April, the eastern coast experiences an earlier peak around February. Transmission was estimated to start in southeast districts before southwest districts, suggesting that indoor residual spraying should be completed in the same order. In regions where the data suggested conflicting seasonal signals or two transmission seasons, estimates of seasonal features had larger deviations and therefore less certainty.. Monthly health facility data can be used to establish seasonal patterns in malaria burden and augment the information provided by household prevalence surveys. The proposed modelling framework allows for evidence-based and cohesive inferences on location-specific seasonal characteristics. As health surveillance systems continue to improve, it is hoped that more of such data will be available to improve our understanding and planning of intervention strategies.

Topics: Data Analysis; Health Facilities; Humans; Incidence; Madagascar; Malaria; Seasons

Mosquito-borne diseases like malaria are a major public health problem in tropical countries, such as Madagascar. Female Anopheles mosquito vectors the human malaria parasites (Plasmodium spp.) and is important indicator in malaria surveillance activities. Among the various means of vector control in Madagascar, the use of attractants for mass trapping of target species could be an alternative to insecticides. The aim of this study is to evaluate whether 4-hydroxycoumarin can be used as an attractant for anthropophilic Anopheles spp. vectors of malaria. For this, a field study was conducted using CDC light traps in the village of Ambohidray, Madagascar. 16 days of trapping was conducted and four replicates nights were performed for each product tested. 4-hydroxycoumarin, octenol and two types of blend of these products were tested. The results showed that 4-hydroxycoumarin (2 mg) have a significant attractive effect on Anopheles spp. and significant selectivity towards Anopheles gambiae s.l, and Anopheles mascarensis which are both significant malaria vectors in Madagascar. A synergy of 4-hydroxycoumarin with octenol was found to attract these mosquito vectors. A significant decrease in vector populations was observed during this experiment. These results suggest that 4-hydroxycoumarin could be useful for malaria surveillance and the control of vector populations.

Topics: 4-Hydroxycoumarins; Animals; Anopheles; Chemotactic Factors; Female; Geography; Humans; Humidity; Madagascar; Malaria; Mosquito Control; Mosquito Vectors; Pheromones; Temperature

Deforestation and land use change is widespread in Madagascar, altering local ecosystems and creating opportunities for disease vectors, such as the Anopheles mosquito, to proliferate and more easily reach vulnerable, rural populations. Knowledge of risk factors associated with malaria infections is growing globally, but these associations remain understudied across Madagascar's diverse ecosystems experiencing rapid environmental change. This study aims to uncover socioeconomic, demographic, and ecological risk factors for malaria infection across regions through analysis of a large, cross-sectional dataset.. The objectives were to assess (1) the ecological correlates of malaria vector breeding through larval surveys, and (2) the socioeconomic, demographic, and ecological risk factors for malaria infection in four ecologically distinct regions of rural Madagascar. Risk factors were determined using multilevel models for the four regions included in the study.. The presence of aquatic agriculture (both within and surrounding communities) is the strongest predictive factor of habitats containing Anopheles larvae across all regions. Ecological and socioeconomic risk factors for malaria infection vary dramatically across study regions and range in their complexity.. Risk factors for malaria transmission differ dramatically across regions of Madagascar. These results may help stratifying current malaria control efforts in Madagascar beyond the scope of existing interventions.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animal Distribution; Animals; Anopheles; Child; Child, Preschool; Cross-Sectional Studies; Demography; Ecosystem; Female; Humans; Infant; Madagascar; Malaria; Male; Middle Aged; Mosquito Vectors; Risk Factors; Socioeconomic Factors; Young Adult

Madagascar's Malaria National Strategic Plan 2018-2022 calls for progressive malaria elimination beginning in low-incidence districts (< 1 case/1000 population). Optimizing access to prompt diagnosis and quality treatment and improving outbreak detection and response will be critical to success. A malaria elimination readiness assessment (MERA) was performed in health facilities (HFs) of selected districts targeted for malaria elimination.. A mixed methods survey was performed in September 2018 in five districts of Madagascar. Randomly selected HFs were assessed for availability of malaria commodities and frequency of training and supervision conducted. Health providers (HPs) and community health volunteers (CHVs) were interviewed, and outpatient consultations at HFs were observed. To evaluate elimination readiness, a composite score ranging from 0 to 100 was designed from all study tools and addressed four domains: (1) resource availability, (2) case management (CM), (3) data management and use, and (4) training, supervision, and technical assistance; scores were calculated for each HF catchment area and district based on survey responses. Stakeholder interviews on malaria elimination planning were conducted at national, regional and district levels.. A quarter of the 35 HFs surveyed had no rapid diagnostic tests (RDTs). Of 129 patients with reported or recorded fever among 300 consultations observed, HPs tested 56 (43%) for malaria. Three-quarters of the 35 HF managers reviewed data for trends. Only 68% of 41 HPs reported receiving malaria-specific training. Of 34 CHVs surveyed, 24% reported that treating fever was no longer among their responsibilities. Among treating CHVs, 13 (50%) reported having RDTs, and 11 (42%) had anti-malarials available. The average district elimination readiness score was 52 out of 100, ranging from 48 to 57 across districts. Stakeholders identified several challenges to commodity management, malaria CM, and epidemic response related to lack of training and funding disruptions.. This evaluation highlighted gaps in malaria CM and elimination readiness in Madagascar to address during elimination planning. Strategies are needed that include training, commodity provision, supervision, and support for CHVs. The MERA can be repeated to assess progress in filling identified gaps and is a feasible tool that could be used to assess elimination targets in other countries.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antimalarials; Case Management; Child; Child, Preschool; Disease Eradication; Health Facilities; Humans; Infant; Madagascar; Malaria; Middle Aged; Young Adult

The Demographic and Health Surveys (DHS) Program has supported three household Malaria Indicator Surveys (MIS) in Madagascar. The results of 13 key malaria indicators from these surveys have been mapped as continuous surfaces using model-based geostatistical methods. The opportunities and limitations of these mapped outputs were discussed during a workshop in Antananarivo, Madagascar in July 2018, attended by 15 representatives from various implementation, policy and research stakeholder institutions in Madagascar. Participants evaluated the findings from the maps, using these to develop figures and narratives to support their work in the control of malaria in Madagascar.

Topics: Humans; Madagascar; Malaria; Stakeholder Participation; Surveys and Questionnaires

This study aims to assess the adherence of private health providers to the use of malaria rapid diagnostic tests (RDTs) and to the prescription of artemisinin-containing combinations (ACT) in patients with uncomplicated malaria.. We conducted an analytical, retrospective and cross-sectional study in 11 Madagascar's health districts divided into four epidemiological strata in September and in October 2015. A total of 43 health providers from 39 private health care facilities (PHF) were interviewed and visited.. Health providers declared having read the malaria management manual in 16.3% of cases (4/43). Only one quarter (25.6%) of health providers had RDTs in their office. ACT was reported as "first-line drug" for the treatment of uncomplicated malaria by 83.7% of health providers. In practice, 55.6% of health providers had doubts about the results of the RDTs. The use of antimalarial drugs, despite having had negative RDTs results (38.2%), was more frequent among those who had raised doubts (p = 0.03). Conversely, despite having had positive RDTs results, half of the health providers did not prescribe ACT (50%). The decision to not participate in periodic reviews by the Health District (p = 0.05) negatively influenced the adherence to the policies.. The low adherence of private health providers to the national guidelines for the management of uncomplicated malaria raises questions about the importance of exercising more control over health providers activities.

Topics: Antimalarials; Artemisinins; Cross-Sectional Studies; Diagnostic Tests, Routine; Drug Therapy, Combination; Guideline Adherence; Humans; Madagascar; Malaria; Practice Guidelines as Topic; Private Sector; Retrospective Studies

On the island of Madagascar, prior to the arrival of the Europeans, some pathologies including malaria, locally known as tazo (fever), were already described. As part of the Malagasy traditional knowledge, traditional medicine mainly based on the use of herbal remedies is part of the malaria treatment still today. Across the country, hundreds of plants are identified as antimalarial, and some compounds from plants show interesting in vitro activities against human Plasmodium. However, it has become clear that most of the antimalarial herbal remedies traditionally used are not efficient antimalarials. In order to identify authentic antimalarial herbal remedies, methodical approaches should range from plant selection to biological screening. In this paper, we share our point of view based on our experience on antimalarial plants in Madagascar.

Topics: Antimalarials; Humans; Madagascar; Malaria; Plants, Medicinal; Plasmodium falciparum

The Madagascar National Strategic Plan for Malaria Control 2018 (NSP) outlines malaria control pre-elimination strategies that include detailed goals for mosquito control. Primary surveillance protocols and mosquito control interventions focus on indoor vectors of malaria, while many potential vectors feed and rest outdoors. Here we describe the application of tools that advance our understanding of diversity, host choice, and Plasmodium infection in the Anopheline mosquitoes of the Western Highland Fringe of Madagascar.. We employed a modified barrier screen trap, the QUadrant Enabled Screen Trap (QUEST), in conjunction with the recently developed multiplex BLOOdmeal Detection Assay for Regional Transmission (BLOODART). We captured a total of 1252 female Anopheles mosquitoes (10 species), all of which were subjected to BLOODART analysis. QUEST collection captured a heterogenous distribution of mosquito density, diversity, host choice, and Plasmodium infection. Concordance between Anopheles morphology and BLOODART species identifications ranged from 93-99%. Mosquito feeding behavior in this collection frequently exhibited multiple blood meal hosts (single host = 53.6%, two hosts = 42.1%, three hosts = 4.3%). The overall percentage of human positive bloodmeals increased between the December 2017 and the April 2018 timepoints (27% to 44%). Plasmodium positivity was frequently observed in the abdomens of vectors considered to be of secondary importance, with an overall prevalence of 6%.. The QUEST was an efficient tool for sampling exophilic Anopheline mosquitoes. Vectors considered to be of secondary importance were commonly found with Plasmodium DNA in their abdomens, indicating a need to account for these species in routine surveillance efforts. Mosquitoes exhibited multiple blood feeding behavior within a gonotrophic cycle, with predominantly non-human hosts in the bloodmeal. Taken together, this complex feeding behavior could enhance the role of multiple Anopheline species in malaria transmission, possibly tempered by zoophilic feeding tendencies.

Topics: Animals; Anopheles; Blood; Disease Vectors; Epidemiological Monitoring; Feeding Behavior; Female; Host-Parasite Interactions; Humans; Madagascar; Malaria; Mosquito Control; Plasmodium

Malaria remains one of the leading causes of morbidity and mortality among children under five years old in many low- and middle-income countries. In this study, we examined how malaria-related ideational factors may influence care-seeking behavior among female caregivers of children under five with fever. Data came from population-based surveys conducted in 2014-2015 by U.S. Agency for International Development-funded surveys in Madagascar, Mali, and Nigeria. The outcome of interest was whether a child under five with fever within two weeks prior to the survey was brought to a formal health facility for care. Results show a wide variation in care-seeking practices for children under five with fever across countries. Seeking care for febrile children under five in the formal health sector is far from a norm in the study countries. Important ideational factors associated with care-seeking behavior included caregivers' perceived social norms regarding treatment of fever among children under five in Nigeria and Madagascar, and caregiver's knowledge of the cause of malaria in Mali. Findings indicate that messages aimed to increase malaria-related knowledge should be tailored to the specific country, and that interventions designed to influence social norms about care-seeking are likely to result in increased care-seeking behavior for fever in children under five.

Topics: Adult; Caregivers; Child, Preschool; Female; Fever; Humans; Infant; Madagascar; Malaria; Male; Mali; Nigeria; Patient Acceptance of Health Care

The use of insecticide-treated bed nets (ITNs) is crucial to the prevention, control, and elimination of malaria. Using household surveys conducted in 2014-2015 by the Health Communication Capacity Collaborative project in Madagascar, Mali, and Nigeria, we compared a model of psychosocial influence, called Ideation, to examine how malaria-related variables influence individual and household bed net use in each of these countries. Evaluations of non-malaria programs have confirmed the value of the ideational approach, but it is infrequently used to guide malaria interventions. The study objective was to examine how well this model could identify potentially effective malaria prevention approaches in different contexts.. Sampling and survey designs were similar across countries. A multi-stage random sampling process selected female caregivers with at least one child under 5 years of age for interviews. Additional data were collected from household heads about bed net use and other characteristics of household members. The caregiver survey measured psychosocial variables that were subjected to bivariate and multivariate analysis to identify significant ideational variables related to bed net use.. In all three countries, children and adolescents over five were less likely to sleep under a net compared to children under five (OR = 0.441 in Madagascar, 0.332 in Mali, 0.502 in Nigeria). Adults were less likely to sleep under a net compared to children under five in Mali (OR = 0.374) and Nigeria (OR = 0.448), but not Madagascar. In all countries, the odds of bed net use were lower in larger compared to smaller households (OR = 0.452 in Madagascar and OR = 0.529 in Nigeria for households with 5 or 6 members compared to those with less than 5; and OR = 0.831 in Mali for larger compared to smaller households). Of 14 common ideational variables examined in this study, six were significant predictors in Madagascar (all positive), three in Mali (all positive), and two in Nigeria (both negative).. This research suggests that the systematic use of this model to identify relevant ideational variables in a particular setting can guide the development of communication strategies and messaging, thereby improving the effectiveness of malaria prevention and control.

Topics: Adolescent; Adult; Caregivers; Child; Child, Preschool; Family Characteristics; Female; Health Communication; Humans; Infant; Infant, Newborn; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Mali; Models, Psychological; Nigeria; Surveys and Questionnaires; Thinking

Reliable measures of disease burden over time are necessary to evaluate the impact of interventions and assess sub-national trends in the distribution of infection. Three Malaria Indicator Surveys (MISs) have been conducted in Madagascar since 2011. They provide a valuable resource to assess changes in burden that is complementary to the country's routine case reporting system.. A Bayesian geostatistical spatio-temporal model was developed in an integrated nested Laplace approximation framework to map the prevalence of Plasmodium falciparum malaria infection among children from 6 to 59 months in age across Madagascar for 2011, 2013 and 2016 based on the MIS datasets. The model was informed by a suite of environmental and socio-demographic covariates known to influence infection prevalence. Spatio-temporal trends were quantified across the country.. Despite a relatively small decrease between 2013 and 2016, the prevalence of malaria infection has increased substantially in all areas of Madagascar since 2011. In 2011, almost half (42.3%) of the country's population lived in areas of very low malaria risk (<1% parasite prevalence), but by 2016, this had dropped to only 26.7% of the population. Meanwhile, the population in high transmission areas (prevalence >20%) increased from only 2.2% in 2011 to 9.2% in 2016. A comparison of the model-based estimates with the raw MIS results indicates there was an underestimation of the situation in 2016, since the raw figures likely associated with survey timings were delayed until after the peak transmission season.. Malaria remains an important health problem in Madagascar. The monthly and annual prevalence maps developed here provide a way to evaluate the magnitude of change over time, taking into account variability in survey input data. These methods can contribute to monitoring sub-national trends of malaria prevalence in Madagascar as the country aims for geographically progressive elimination.

Topics: Child, Preschool; Female; History, 21st Century; Humans; Infant; Madagascar; Malaria; Malaria, Falciparum; Male; Plasmodium falciparum; Prevalence; Surveys and Questionnaires

The increasing use of malaria diagnostic tests reveals a growing proportion of patients with fever but no malaria. Clinicians and health care workers in low-income countries have few tests to diagnose causes of fever other than malaria although several diseases share common symptoms. We propose here to assess etiologies of fever in Madagascar to ultimately improve management of febrile cases.. Consenting febrile outpatients aged 6 months and older were recruited in 21 selected sentinel sites throughout Madagascar from April 2014 to September 2015. Standard clinical examinations were performed, and blood and upper respiratory specimens were taken for rapid diagnostic tests and molecular assays for 36 pathogens of interest for Madagascar in terms of public health, regardless of clinical status.. A total of 682 febrile patients were enrolled. We detected at least one pathogen in 40.5% (276/682) of patients and 6.2% (42/682) with co-infections. Among all tested patients, 26.5% (181/682) had at least one viral infection, 17.0% (116/682) had malaria and 1.0% (7/682) presented a bacterial or a mycobacterial infection. None or very few of the highly prevalent infectious agents in Eastern Africa and Asia were detected in this study, such as zoonotic bacteria or arboviral infections.. These results raise questions about etiologies of fever in Malagasy communities. Nevertheless, we noted that viral infections and malaria still represent a significant proportion of causes of febrile illnesses. Interestingly our study allowed the detection of pathogens of public health interest such as Rift Valley Fever Virus but also the first case of laboratory-confirmed leptospirosis infection in Madagascar.

Topics: Adolescent; Adult; Aged; Bacterial Infections; Child; Child, Preschool; Community Health Centers; Female; Fever; Humans; Madagascar; Malaria; Male; Middle Aged; Prospective Studies; Public Health; Virus Diseases; Young Adult

In areas where malaria epidemiology is spatially and temporally heterogeneous, human-mediated parasite importation can result in non-locally acquired clinical cases and outbreaks in low-transmission areas. Using mobility estimates derived from the mobile phone data and spatial malaria prevalence data, we identify travel routes relevant to malaria transmission in Madagascar. We find that the primary hubs of parasite importation are in a spatially connected area of the central highlands. Surprisingly, sources of these imported infections are not spatially clustered. We then related these source locations directly to clinical cases in the low-transmission area of the capital. We find that in the capital, a major sink, the primary sources of infection are along the more populated coastal areas, although these sources are seasonally variable. Our results have implications for targeting interventions at source locations to achieve local or national malaria control goals.

Topics: Animals; Cell Phone; Geography; Humans; Madagascar; Malaria; Plasmodium; Population Surveillance; Prevalence; Seasons; Travel

The private sector supplies anti-malarial treatment for large proportions of patients in sub-Saharan Africa. Following the large-scale piloting of the Affordable Medicines Facility-malaria (AMFm) from 2010 to 2011, a private sector co-payment mechanism (CPM) provided continuation of private sector subsidies for quality-assured artemisinin combination therapies (QAACT). This article analyses for the first time the extent to which improvements in private sector QAACT supply and distribution observed during the AMFm were maintained or intensified during continuation of the CPM through 2015 in Kenya, Madagascar, Nigeria, Tanzania and Uganda using repeat cross-sectional outlet survey data.. QAACT market share in all five countries increased during the AMFm period (p < 0.001). According to the data from the last ACTwatch survey round, in all study countries except Madagascar, AMFm levels of private sector QAACT availability were maintained or improved. In 2014/15, private sector QAACT availability was greater than 70% in Nigeria (84.3%), Kenya (70.5%), Tanzania (83.0%) and Uganda (77.1%), but only 11.2% in Madagascar. QAACT market share was maintained or improved post-AMFm in Nigeria, Tanzania and Uganda, but statistically significant declines were observed in Kenya and Madagascar. In 2014/5, QAACT market share was highest in Kenya and Uganda (48.2 and 47.5%, respectively) followed by Tanzania (39.2%), Nigeria (35.0%), and Madagascar (7.0%). Four of the five countries experienced significant decreases in median QAACT price during the AMFm period. Private sector QAACT prices were maintained or further reduced in Tanzania, Nigeria and Uganda, but prices increased significantly in Kenya and Madagascar. SP prices were consistently lower than those of QAACT in the AMFm period, with the exception of Kenya and Tanzania in 2011, where they were equal. In 2014/5 QAACT remained two to three times more expensive than the most popular non-artemisinin therapy in all countries except Tanzania.. Results suggest that a private sector co-payment mechanism for QAACT implemented at national scale for 5 years was associated with positive and sustained improvements in QAACT availability, price and market share in Nigeria, Tanzania and Uganda, with more mixed results in Kenya, and few improvements in Madagascar. The subsidy mechanism as implemented over time across countries was not sufficient on its own to achieve optimal QAACT uptake. Supporting interventions to address continued availability and distribution of non-artemisinin therapies, and to create demand for QAACT among providers and consumers need to be effectively implemented to realize the full potential of this subsidy mechanism. Furthermore, there is need for comprehensive market assessments to identify contemporary market barriers to high coverage with both confirmatory testing and appropriate treatment.

Topics: Africa South of the Sahara; Antimalarials; Artemisinins; Commerce; Drug Combinations; Health Facilities; Madagascar; Malaria; Pilot Projects; Private Sector

It was previously reported that a malaria infection may interfere with the specificity of a commercial ELISA test against Zika virus (ZIKV). We analyzed 1,216 plasma samples from healthy, pregnant women collected in two sites in Madagascar in 2010 for ZIKV antibodies using a commercial ELISA and for Plasmodium infection by PCR. This screen revealed six putative ZIKV-positive samples by ELISA. These results could not be confirmed by indirect immunofluorescence assays or virus neutralization tests. Four of these six samples were also positive for P. falciparum. We noted that the frequency of malaria positivity was higher in ZIKV-ELISA positive samples (50% and 100% in the two study sites) than ZIKV-negative samples (17% and 10%, respectively), suggesting that malaria may have led to false ZIKV-ELISA positives.

Topics: Antibodies, Neutralizing; Antibodies, Viral; Coinfection; Cross-Sectional Studies; Enzyme-Linked Immunosorbent Assay; Female; Geography; Humans; Madagascar; Malaria; Neutralization Tests; Population Surveillance; Pregnancy; Sensitivity and Specificity; Seroepidemiologic Studies; Zika Virus; Zika Virus Infection

Continuous distribution of insecticide-treated nets (ITNs) is thought to be an effective mechanism to maintain ITN ownership and access between or in the absence of mass campaigns, but evidence is limited. A community-based ITN distribution pilot was implemented and evaluated in Toamasina II District, Madagascar, to assess this new channel for continuous ITN distribution.. Beginning 9 months after the December 2012 mass campaign, a community-based distribution pilot ran for an additional 9 months, from September 2013 to June 2014. Households requested ITN coupons from community agents in their village. After verification by the agents, households exchanged the coupon for an ITN at a distribution point. The evaluation was a two-stage cluster survey with a sample size of 1125 households. Counterfactual ITN ownership and access were calculated by excluding ITNs received through the community pilot.. At the end of the pilot, household ownership of any ITN was 96.5%, population access to ITN was 81.5 and 61.5% of households owned at least 1 ITN for every 2 people. Without the ITNs provided through the community channel, household ownership of any ITN was estimated at 74.6%, population access to an ITN at 55.5%, and households that owned at least 1 ITN for 2 people at only 34.7%, 18 months after the 2012 campaign. Ownership of community-distributed ITNs was higher among the poorest wealth quintiles. Over 80% of respondents felt the community scheme was fair and simple to use.. Household ITN ownership and population ITN access exceeded RBM targets after the 9-month community distribution pilot. The pilot successfully provided coupons and ITNs to households requesting them, particularly for the least poor wealth quintiles, and the scheme was well-perceived by communities. Further research is needed to determine whether community-based distribution can sustain ITN ownership and access over the long term, how continuous availability of ITNs affects household net replacement behaviour, and whether community-based distribution is cost-effective when combined with mass campaigns, or if used with other continuous channels instead of mass campaigns.

Topics: Adult; Delivery of Health Care; Family Characteristics; Female; Humans; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Middle Aged; Mosquito Control; Ownership; Pilot Projects

The performance of the malaria rapid diagnostic test OnSite-for detecting pan specific pLDH and Plasmodium falciparum specific HRP2 - was assessed during the malaria transmission peak period in Miandrivazo, in the southwestern part of Madagascar from April 20 to May 6, 2010. At the laboratory, the quality control OnSite Malaria Rapid Test according to the WHO/TDR/FIND method demonstrated that the test had good sensitivity. Of the 218 OnSite tests performed at the Miandrivazo Primary Health Center on patients with fever or a recent history of fever, four (1.8%, 95% CI: 0.6-4.9%) were invalid. Ninety four (43,1%) cases of malaria were confirmed by microscopy, of which 90 were P. falciparum malaria and 4 Plasmodium vivax malaria. With a Cohen's kappa coefficient of 0.94, the agreement between microscopy and OnSite is excellent. Compared with the rapid test CareStart™ commonly used within the public health structures in Madagascar, the sensitivity and specificity of the OnSite test were 97.9% and 96.8%.

Topics: Adolescent; Adult; Antigens, Protozoan; Blood Chemical Analysis; Child; Child, Preschool; Diagnostic Tests, Routine; Female; Humans; L-Lactate Dehydrogenase; Madagascar; Malaria; Male; Mass Screening; Middle Aged; Protozoan Proteins; Quality Control; Reagent Kits, Diagnostic; Sensitivity and Specificity; Time Factors; Young Adult

Insecticide-based vector control, which comprises use of insecticide-treated bed nets (ITNs) and indoor residual spraying (IRS), is the key method to malaria control in Madagascar. However, its effectiveness is threatened as vectors become resistant to insecticides. This study investigated the resistance status of malaria vectors in Madagascar to various insecticides recommended for use in ITNs and/or IRS.. WHO tube and CDC bottle bioassays were performed on populations of Anopheles gambiae (s.l.), An. funestus and An. mascarensis. Adult female An. gambiae (s.l.) mosquitoes reared from field-collected larvae and pupae were tested for their resistance to DDT, permethrin, deltamethrin, alpha-cypermethrin, lambda-cyhalothrin, bendiocarb and pirimiphos-methyl. Resting An. funestus and An. mascarensis female mosquitoes collected from unsprayed surfaces were tested against permethrin, deltamethrin and pirimiphos-methyl. The effect on insecticide resistance of pre-exposure to the synergists piperonyl-butoxide (PBO) and S,S,S-tributyl phosphorotrithioate (DEF) also was assessed. Molecular analyses were done to identify species and determine the presence of knock-down resistance (kdr) and acetylcholinesterase resistance (ace-1. Anopheles funestus and An. mascarensis were fully susceptible to permethrin, deltamethrin and pirimiphos-methyl. Anopheles gambiae (s.l.) was fully susceptible to bendiocarb and pirimiphos-methyl. Among the 17 An. gambiae (s.l.) populations tested for deltamethrin, no confirmed resistance was recorded, but suspected resistance was observed in two sites. Anopheles gambiae (s.l.) was resistant to permethrin in four out of 18 sites (mortality 68-89%) and to alpha-cypermethrin (89% mortality) and lambda-cyhalothrin (80% and 85%) in one of 17 sites, using one or both assay methods. Pre-exposure to PBO restored full susceptibility to all pyrethroids tested except in one site where only partial restoration to permethrin was observed. DEF fully suppressed resistance to deltamethrin and alpha-cypermethrin, while it partially restored susceptibility to permethrin in two of the three sites. Molecular analysis data suggest absence of kdr and ace-1. This study suggests involvement of detoxifying enzymes in the phenotypic resistance of An. gambiae (s.l.) to pyrethroids. The absence of resistance in An. funestus and An. mascarensis to pirimiphos-methyl and pyrethroids and in An. gambiae (s.l.) to carbamates and organophosphates presents greater opportunity for managing resistance in Madagascar.

Topics: Acetylcholinesterase; Animals; Anopheles; Female; Insecticide Resistance; Insecticide-Treated Bednets; Insecticides; Larva; Madagascar; Malaria; Mosquito Control; Mutation; Nitriles; Permethrin; Pupa; Pyrethrins

Madagascar conducted the first two phases of a national free mass distribution campaign of long-lasting insecticidal nets (LLINs) during a political crisis in 2009 aiming to achieve coverage of two LLINs per household as part of the National Malaria Control Strategy. The campaign targeted households in 19 out of 91 total health districts.. A community-based cross-sectional household survey using a three-stage cluster sample design was conducted four months post campaign to assess LLIN ownership, access and use. Multivariable logistic regression analysis was used to identify factors associated with household LLIN access and individual LLIN use.. A total of 2211 households were surveyed representing 8867 people. At least one LLIN was present in 93.5% (95% confidence interval [CI], 91.6-95.5%) of households and 74.8% (95% CI, 71.0-78.6%) owned at least two LLINs. Access measured as the proportion of the population that could potentially be covered by household-owned LLINs was 77.2% (77.2% (95% CI, 72.9-81.3%) and LLIN use by all individuals was 84.2% (95% CI, 81.2-87.2%). LLIN use was associated with knowledge of insecticide treated net use to prevent malaria (OR = 3.58, 95% CI, 1.85-6.94), household ownership of more LLINs (OR 2.82, 95% CI 1.85-4.3), presence of children under five (OR = 2.05, 95% CI, 1.67-2.51), having traveled to the distribution point and receiving information about hanging a bednet (OR = 1.56, 95% CI, 1.41-1.74), and having received a post-campaign visit by a community mobilizer (OR = 1.75, 95% CI, 1.26-2.43). Lower LLIN use was associated with increasing household size (OR = 0.81 95% CI 0.77-0.85) and number of sleeping spaces (OR = 0.55, 95% CI, 0.44-0.68).. A large scale free mass LLIN distribution campaign was feasible and effective at achieving high LLIN access and use in Madagascar. Campaign process indicators highlighted potential areas for strengthening implementation to optimize access and equity.

Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Child; Child, Preschool; Cross-Sectional Studies; Female; Humans; Infant; Infant, Newborn; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Middle Aged; Mosquito Control; Ownership; Pregnancy; Young Adult

There is growing awareness of the likely impact increased numbers of LLINs will have on the environment, if not disposed of or recycled appropriately. As part of a World Health Organization (WHO) and United Nations Environment Programme (UNEP) pilot study to assess environmentally-sound and cost-effective LLIN recycling strategies, the USAID-Deliver Project collected 22,559 used bed nets in Madagascar. A social science study was conducted to provide data on socio-cultural factors related to collection and replacement of LLINs, including impact on primary and other net uses.. Ethnographic exploratory research was carried out following the pilot USAID-Deliver net collection and recycling campaign in Betioky, Tsihombe, Fenerive Est and Ambanja districts of Madagascar, triangulating participant observation, interviewing and group discussions. Sampling was theoretical and data analysis was a continuous and iterative process concurrent to data collection. Final analysis was conducted using NVivo10.. The following themes emerged as contributing to the success of collecting expired LLINs in the community for recycling purposes: (i) net adequacy and preference: characteristic differences between collected and newly distributed nets lead to communities' reticence to relinquish old nets before confirming new nets were appropriate for intended use. Where newly distributed nets failed to meet local requirements, this was expected to increase alternative uses and decrease household turn over. (ii) Net collection strategies: the net collection campaign brought net use out of the private sphere and into the public arena. Net owners reported feeling ashamed when presenting damaged nets in public for collection, leading to reduced net relinquishment. (iii) Net lifecycle: communities perceived nets as being individually owned and economic value was attributed both to good-condition nets for sleeping and to worn nets for alternative/secondary purposes. Collecting nets at the stage of waste rather than at their prescribed end of life was locally acceptable.. The collection of LLINs for recycling/disposal can lead to lower coverage under certain conditions. Collecting used LLINs may be appropriate under the following conditions: (i) nets are collected at the stage of waste; (ii) new nets are in line with community preferences; and (iii) collection strategies have been agreed upon within the community prior to replacement activities. Any collection/recycling of old LLINs should be based on in-depth understanding of the local context and include participatory processes to prevent reduced coverage.

Topics: Cost-Benefit Analysis; Ethical Analysis; Family Characteristics; Insecticide-Treated Bednets; Madagascar; Malaria; Mosquito Control; Ownership; Pilot Projects; Recycling; Socioeconomic Factors

Long-lasting insecticidal mosquito nets (LLINs) are highly effective for malaria prevention. However, it is also clear that durability monitoring is essential to predict when, post-distribution, a net population, no longer meets minimum WHO standards and needs to be replaced. Following a national distribution campaign in 2013, we tracked two durability indicators, physical integrity and bio-efficacy at six and 12 months post-distribution. While the loss of net integrity during this period was in line with expectations for a one-year net life, bio-efficacy results suggested that nets were losing insecticidal effect faster than expected. The rate of bio-efficacy loss varied significantly between different net brands.. We tested 600 randomly selected LLINs, 200 from each of three net brands. Each brand came from different eco-epidemiological zones reflecting the original distribution scheme. Fabric integrity (size and number of holes) was quantified using the proportional hole index (pHI). A subsample of the nets, 134 new nets, 150 at six months and 124 at 12 months, were then tested for bio-efficacy using the World Health Organization (WHO) recommended method.. Three net types, Netprotect®, Royalsentry® and Yorkool®, were followed. After six months, 54%, 39% and 45%, respectively, showed visible loss of integrity. The median pHI by type was estimated to be one, zero and one respectively. The percentage of damaged nets increased after 12 months such that 83.5%, 74% and 68.5%, had holes. The median pHI for each brand of nets was 47.5, 47 and 23. No significant difference in the estimated pHI at either six or 12 months was observed. There was a statistically significant difference in the proportion of hole size category between the three brands (χ. These findings suggest that there is a need for better net quality control before distribution. More frequent replacement of LLINs is probably not an option programmatically. Regardless of prior approval, LLIN durability monitoring for quality assessment as well as net loss following distribution is necessary to improve malaria control efforts.

Topics: Humans; Insecticide-Treated Bednets; Insecticides; Madagascar; Malaria; Mosquito Control; Quality Control; Textiles; Time Factors; World Health Organization

The use of a malaria early warning system (MEWS) to trigger prompt public health interventions is a key step in adding value to the epidemiological data routinely collected by sentinel surveillance systems.. This study describes a system using various epidemic thresholds and a forecasting component with the support of new technologies to improve the performance of a sentinel MEWS. Malaria-related data from 21 sentinel sites collected by Short Message Service are automatically analysed to detect malaria trends and malaria outbreak alerts with automated feedback reports.. Roll Back Malaria partners can, through a user-friendly web-based tool, visualize potential outbreaks and generate a forecasting model. The system already demonstrated its ability to detect malaria outbreaks in Madagascar in 2014.. This approach aims to maximize the usefulness of a sentinel surveillance system to predict and detect epidemics in limited-resource environments.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Epidemics; Female; Forecasting; Humans; Infant; Infant, Newborn; Internet; Madagascar; Malaria; Male; Middle Aged; Prospective Studies; Retrospective Studies; Sentinel Surveillance; Software; Text Messaging; Young Adult

The malaria burden in Madagascar dropped down last decade, largely due to scale-up of control measures. Nevertheless, a significant rise of malaria cases occurred in 2011-2012 in two regions of the rainy South-Eastern Madagascar, where malaria is considered as mesoendemic and the population is supposed to be protected by its acquired immunity against Plasmodium. A multidisciplinary investigation was conducted in order to identify the causes of the outbreak.. In March 2012, a cross-sectional study was conducted in 20 randomly selected clusters, involving the rapid diagnostic testing of all ≥6 month-old members of households and a questionnaire about socio-demographic data and exposure to malaria control interventions. Changes in environmental conditions were evaluated by qualitative interview of local authorities, climatic conditions were evaluated by remote-sensing, and stock outs of malaria supplies in health facilities were evaluated by quantitative means. Two long-lasting insecticidal nets (LLINs) were sampled in each cluster in order to evaluate their condition and the remanence of their insecticidal activity. The entomological investigation also encompassed the collection Anopheles vectors in two sites, and the measure of their sensitivity to deltamethrin.. The cross-sectional survey included 1615 members of 440 households. The mean Plasmodium infection rate was 25.6 % and the mean bed net use on the day before survey was 71.1 %. The prevalence of Plasmodium infections was higher in 6-14 year-old children (odds ratio (OR) 7.73 [95 % CI 3.58-16.68]), in rural areas (OR 6.25 [4.46-8.76]), in poorest socio-economic tercile (OR 1.54 [1.13-2.08]), and it was lower in individuals sleeping regularly under the bed net (OR 0.51 [0.32-0.82]). Stock outs of anti-malarial drugs in the last 6 months have been reported in two third of health facilities. Rainfalls were increased as compared with the three previous rainy seasons. Vectors collected were sensitive to pyrethroids. Two years after distribution, nearly all LLINs collected showed a loss of physical integrity and insecticide activity,. Increased rainfall, decreasing use and reduced insecticide activity of long-lasting insecticide-treated nets, and drug shortages may have been responsible for, or contributed to, the outbreak observed in South-Eastern Madagascar in 2011-2012. Control interventions for malaria elimination must be sustained at the risk of triggering harmful epidemics, even in zones of high transmission.

Topics: Adolescent; Adult; Antimalarials; Child; Child, Preschool; Cross-Sectional Studies; Disease Outbreaks; Female; Humans; Infant; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Middle Aged; Nitriles; Plasmodium; Pyrethrins; Young Adult

Madagascar, as other malaria endemic countries, depends mainly on international funding for the implementation of malaria control interventions (MCI). As these funds no longer increase, policy makers need to know whether these MCI actually provide the expected protection. This study aimed at measuring the effectiveness of MCI deployed in all transmission patterns of Madagascar in 2012-2013 against the occurrence of clinical malaria cases.. From September 2012 to August 2013, patients consulting for non-complicated malaria in 31 sentinel health centres (SHC) were asked to answer a short questionnaire about long-lasting insecticidal nets (LLIN) use, indoor residual spraying (IRS) in the household and intermittent preventive treatment of pregnant women (IPTp) intake. Controls were healthy all-ages individuals sampled from a concurrent cross-sectional survey conducted in areas surrounding the SHC. Cases and controls were retained in the database if they were resident of the same communes. The association between Plasmodium infection and exposure to MCI was calculated by multivariate multilevel models, and the protective effectiveness (PE) of an intervention was defined as 1 minus the odds ratio of this association.. Data about 841 cases (out of 6760 cases observed in SHC) and 8284 controls was collected. The regular use of LLIN provided a significant 51 % PE (95 % CI [16-71]) in multivariate analysis, excluding in one transmission pattern where PE was -11 % (95 % CI [-251 to 65]) in univariate analysis. The PE of IRS was 51 % (95 % CI [31-65]), and the PE of exposure to both regular use of LLIN and IRS was 72 % (95 % CI [28-89]) in multivariate analyses. Vector control interventions avoided yearly over 100,000 clinical cases of malaria in Madagascar. The maternal PE of IPTp was 73 %.. In Madagascar, LLIN and IRS had good PE against clinical malaria. These results may apply to other countries with similar transmission profiles, but such case-control surveys could be recommended to identify local failures in the effectiveness of MCI.

Topics: Adolescent; Adult; Child; Cross-Sectional Studies; Female; Humans; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Mosquito Control; Young Adult

Although its incidence has been decreasing during the last decade, malaria is still a major public health issue in Madagascar. The use of Long Lasting Insecticidal Nets (LLIN) remains a key malaria control intervention strategy in Madagascar, however, it encounters some obstacles. The present study aimed to explore the local terminology related to malaria, information channels about malaria, attitude towards bed nets, and health care seeking practices in case of fever. This article presents novel qualitative findings about malaria. Until now, no such data has been published for Madagascar.. A comparative qualitative study was carried out at four sites in Madagascar, each differing by malaria epidemiology and socio-cultural background of the populations. Seventy-one semi-structured interviews were conducted with biomedical and traditional caregivers, and members of the local population. In addition, observations of the living conditions and the uses of bed net were conducted.. Due to the differences between local and biomedical perspectives on malaria, official messages did not have the expected impact on population in terms of prevention and care seeking behaviors. Rather, most information retained about malaria was spread through informal information circulation channels. Most interviewees perceived malaria as a disease that is simple to treat. Tazomoka ("mosquito fever"), the Malagasy biomedical word for malaria, was not used by populations. Tazo ("fever") and tazomahery ("strong fever") were the terms more commonly used by members of the local population to refer to malaria related symptoms. According to local perceptions in all areas, tazo and tazomahery were not caused by mosquitos. Each of these symptoms required specific health recourse. The usual fever management strategies consisted of self-medication or recourse to traditional and biomedical caregivers. Usage of bed nets was intermittent and was not directly linked to protection against malaria in the eyes of most Malagasy people.. This article highlights the conflicting understanding of malaria between local perceptions and the biomedical establishment in Madagascar. Local perceptions of malaria present a holistic vision of the disease that includes various social and cultural dimensions, rather than reflecting one universal understanding, as in the biomedical image. The consideration of this "holistic vision" and other socio-cultural aspects surrounding the understanding of malaria is essential in implementing successful control intervention strategies.

Topics: Adult; Aged; Case Management; Female; Fever; Health Knowledge, Attitudes, Practice; Humans; Madagascar; Malaria; Male; Middle Aged; Mosquito Nets; Patient Acceptance of Health Care; Terminology as Topic

Bioassay guided fractionation of a MeOH extract of the stem bark of Syncarpia glomulifera (Myrtaceae) led to the isolation of the two new phloroglucinol derivatives (±)-rhodomyrtosone F (1) and (±)-calliviminone I (2), the three known triterpenes, betulinic acid (3), ursolic acid-3-acetate (4), and ursolic acid (5), and 1-(2,4,6-trihydroxyphenyl)-1-hexanone (6). Compound 1 exhibited strong antiplasmodial activity, while compounds 2-4 were moderately active and 5 and 6 were inactive in this assay. The structures of 1 and 2 were elucidated based on analyses of their mass spectrometric data, 1D and 2D NMR spectra, and comparison with related compounds.

Topics: Antimalarials; Cell Survival; Dose-Response Relationship, Drug; HEK293 Cells; Humans; Malaria; Molecular Structure; Myrtaceae; Parasitic Sensitivity Tests; Phloroglucinol; Plant Bark; Plasmodium falciparum; Structure-Activity Relationship

Because international funding for malaria control is plateauing, affected countries that receive foreign funding are expected to maintain a constant budget while continuing to reduce Plasmodium transmission. To investigate the appropriateness of a malaria control policy in Madagascar, the effectiveness of all currently deployed malaria control interventions (MCIs) was measured.. A nationwide cross-sectional survey was conducted in 2012-2013 at 62 sites throughout Madagascar. A total of 15,746 individuals of all ages were tested for Plasmodium infection using rapid diagnostic tests and were interviewed about their use of long-lasting insecticidal nets (LLINs), indoor residual spraying (IRS), intermittent preventive treatment of pregnant women (IPTp), and exposure to information, education and communication (IEC) campaigns. The association between Plasmodium infection and MCI exposure was calculated using multivariate multilevel models, and the protective effectiveness (PE) of an intervention was defined as one minus the odds ratio of this association.. The individual PE of regular LLIN use was high and significant (41 %, 95 % confidence interval [CI] 23-54), whereas its community PE was not. The PE of IRS at the household level was significant in one transmission pattern only (44 %, 95 % CI 11-65), and the community PE with high IRS coverage (>75 %) was high and significant overall (78 %, 95 % CI 44-91). Using LLINs after IRS increased the PE, and the reciprocal was also true. The maternal PE of IPTp was high but non-significant (65 %, 95 % CI -32 to 91). The PE of IEC was low, non-significant and restricted to certain areas (24 %, 95 % CI -34 to 57).. This snapshot of the effectiveness of MCIs confirms that integrated vector control is required in malaria control policies in Madagascar and suggests combining MCIs when one is questionable. Policymakers should consider the local effectiveness of all deployed MCIs through a similar phase IV assessment.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Communicable Disease Control; Cross-Sectional Studies; Diagnostic Tests, Routine; Disease Transmission, Infectious; Female; Health Education; Health Services Research; Humans; Infant; Madagascar; Malaria; Male; Mass Screening; Middle Aged; Mosquito Control; Surveys and Questionnaires; Young Adult

In the President's Malaria Initiative (PMI)-funded Africa Indoor Residual Spraying Project (AIRS), end-of-day clean-up operations require the safe disposal of wash water resulting from washing the exterior of spray tanks and spray operators' personal protective equipment. Indoor residual spraying (IRS) programs typically use soak pits - large, in-ground filters - to adsorb, filter and then safely degrade the traces of insecticide found in the wash water. Usually these soak pits are permanent installations serving 30 or more operators, located in a central area that is accessible to multiple spray teams at the end of their workday. However, in remote areas, it is often impractical for teams to return to a central soak pit location for cleanup. To increase operational efficiency and improve environmental compliance, the PMI AIRS Project developed and tested mobile soak pits (MSP) in the laboratory and in field applications in Madagascar, Mali, Senegal, and Ethiopia where the distance between villages can be substantial and the road conditions poor. Laboratory testing confirmed the ability of the easily-assembled MSP to reduce effluent concentrations of two insecticides (Actellic 300-CS and Ficam VC) used by the PMI AIRS Project, and to generate the minimal practicable environmental "footprint" in these remote areas. Field testing in the Mali 2014 IRS campaign demonstrated ease of installation and use, resulted in improved and more consistent standards of clean-up, decreased transportation requirements, improved spray team working conditions, and reduced potential for operator exposure to insecticide.

Topics: Animals; Decontamination; Environmental Exposure; Ethiopia; Humans; Insecticides; Madagascar; Malaria; Mali; Mosquito Control; Occupational Exposure; Organothiophosphorus Compounds; Phenylcarbamates; Senegal; Water Pollutants, Chemical

Prof. Philippe Rasoanaivo was a highly dedicated and brilliant scientist in the field of ethnopharmacology. He worked for the Institut Malgache de Recherches Appliquées and the University of Antananarivo, Madagascar. His research was mainly focused on the endemic medicinal and aromatic plants used by traditional healers in Madagascar against a range of parasites, with special reference to Plasmodium spp. In this Editorial, we resumed the key findings of his research activity, with special reference to the discovery of alkaloids that markedly enhance the action of chloroquine against malaria parasites.

Topics: Biomedical Research; Brain Diseases; Ethnopharmacology; History, 20th Century; History, 21st Century; Madagascar; Malaria; Plant Preparations; Plasmodium

Malaria epidemiology in Madagascar is classified into four different areas, ranging from unstable seasonal transmission in the highlands to hyperendemic perennial transmission areas in the costal level. Most malaria studies in Madagascar are focused on symptomatic children. However, because of the low transmission in some areas with correspondingly low level of semi-immunity, adults are also at risk, in particular pregnant women. The objective of this study was to gain information on the genetic epidemiology of malarial infections in pregnant women in order to provide information for malaria control and elimination programmes in Madagascar.. Between May and August 2010, we carried out cross-sectional surveys targeting healthy pregnant women in six locations, three in the coastal area and three in the highlands at 850-1300 m. 1244 blood samples were screened for anti-Plasmodium falciparum antibodies by immunofluorescence test and for malarial infection by realtime-PCR. The prevalence of chloroquine and sulphadoxine-pyrimethamine resistance markers was also determined in all Plasmodium falciparum samples by PCR-RFLP as well as the multiplicity of infection through genotyping six neutral microsatellites.. In the highlands, 67.4% of the women presented antibodies against Plasmodium falciparum and 9.2% were carrying parasites, at the coast 95.6% and 14.8%, respectively. In the mean, 1.2 clones were detected in infected pregnant woman in the highlands and 1.5 at the coast. A higher level of monoclonal infections was found in the highlands (85.4%) compared to the coast (61.8%). Resistance markers for sulphadoxine-pyrimethamine were present only in two sites.. Immunity is triggered in Malagasy highland populations when they are infected with malaria parasites, but these populations could also serve as a reservoir for epidemics.

Topics: Adolescent; Adult; Antibodies, Protozoan; Antimalarials; Asymptomatic Infections; Chloroquine; Drug Combinations; Drug Resistance; Female; Fluorescent Antibody Technique, Indirect; Humans; Madagascar; Malaria; Middle Aged; Molecular Epidemiology; Plasmodium; Pregnancy; Prevalence; Protozoan Proteins; Pyrimethamine; Real-Time Polymerase Chain Reaction; Seroepidemiologic Studies; Sulfadoxine; Young Adult

Topics: Budgets; Female; Health Expenditures; Health Services; Health Services Accessibility; HIV Infections; Humans; Madagascar; Malaria; Male; Plague; Poliomyelitis; Politics

Indoor spraying of insecticides and the use of insecticide-treated bed nets are key strategies for national malaria vector control in the central highlands of Madagascar. During the year 2013, malaria outbreaks were reported by the National Malaria Control Programme in the highlands, including the district of Ankazobe.. Entomological trapping was carried out in April and May 2013 and in March 2014, using human landing catches, collection of mosquitoes resting in stables and in houses by oral aspirators, and Centers for Disease Control and Prevention light traps. Detection of Plasmodium in mosquitoes was carried out on head and thorax of anopheline females by ELISA, CSP and PCR (Plasmodium falciparum, Plasmodium malariae, Plasmodium vivax, or Plasmodium ovale). Human biting rate (HBR), sporozoite index and entomological infection rate (EIR) were calculated for Anopheles funestus, Anopheles arabiensis, Anopheles mascarensis, and Anopheles coustani.. In Ankazobe district, the presence of malaria vectors such as An. funestus, An. arabiensis and An. mascarensis was confirmed, and a new and abundant potential vector, An. coustani was detected. Indeed, one individual of An. funestus and two An. coustani were detected positive with P. falciparum while one An. mascarensis and four An. coustani were positive with P. vivax. For An. coustani, in March 2014, the EIR varied from 0.01 infectious bites/person/month (ipm) outdoors to 0.11 ipm indoors. For An. funestus, in April 2013, the EIR was 0.13 ipm. The highest HBR value was observed for An. coustani, 86.13 ipm outdoors. The highest sporozoite rate was also for An. coustani, 9.5 % of An. coustani caught in stable was sporozoite positive.. The implication of An. coustani in malaria transmission was not previously mentioned in Madagascar. Its very high abundance and the detection of Plasmodium coupled with an opportunistic feeding behaviour in villages with malaria cases supports its role in malaria transmission in Madagascar.

Topics: Animals; Anopheles; Disease Outbreaks; Female; Humans; Insect Vectors; Madagascar; Malaria; Plasmodium

In Madagascar, indoor residual spraying (IRS) with insecticide was part of the national malaria control programme since the middle of the twentieth century. It was mainly employed in the highlands and the foothill areas, which are prone to malaria epidemics. Prior to a policy change foreseeing a shift from DDT to pyrethroids, a study was carried out to assess the entomological and parasitological impacts of IRS in areas with DDT or pyrethroids and in areas without IRS.. The study was carried out from October 2002 to February 2005 in three communes of the western foothill area of Madagascar. Two communes received IRS with DDT in February 2003, then IRS with pyrethroids (alphacypermethrin or deltamethrin) in February 2004. The third commune remained untreated. Mosquitoes were collected at night using human landing catches and early in the morning in resting places. Blood smears were obtained from schoolchildren and microscopically examined for Plasmodium presence.. In total, 18,168 human landing mosquitoes and 12,932 resting anophelines were collected. The Anopheles species caught comprised 10 species. The main and most abundant malaria vector was Anopheles funestus (72.3% of human-seeking malaria vectors caught indoors). After IRS had taken place, this species exhibited a lower human biting rate and a lower sporozoite index. Overall, 5,174 blood smears were examined with a mean plasmodic index of 19.9%. A total of four Plasmodium species were detected. Amongst tested school children the highest plasmodial index was 54.6% in the untreated commune, compared to 19.9% in the commune sprayed with DDT and 11.9% in the commune sprayed with pyrethroid. The highest prevalence of clinical malaria attacks in children present at school the day of the survey was 33% in the untreated commune compared to 8% in the areas which received IRS.. In terms of public health, the present study shows (1) a high efficacy of IRS with insecticide, (2) a similar efficacy of DDT and pyrethroid and (3) a similar efficacy of alphacypermethrin and deltamethrin. The use of IRS with DDT and pyrethroid greatly decreased the vector-human contact, with an associated decrease of the plasmodial index. However malaria transmission did not reach zero, probably due to the exophilic host-seeking and resting behaviours of the malaria vectors, thus avoiding contact with insecticide-treated surfaces indoors. The study highlights the strengths and weaknesses of the IRS implementation and the need for complementary tools for an optimal vector control in Madagascar.

Topics: Animals; Anopheles; Child; DDT; Female; Housing; Humans; Insect Vectors; Insecticides; Madagascar; Malaria; Mosquito Control; Nitriles; Prevalence; Pyrethrins; Seasons

In the last decade, an important scale-up was observed in malaria control interventions. Madagascar entered the process for pre-elimination in 2007. Policy making needs operational indicators, but also indicators about effectiveness and impact of malaria control interventions (MCI). This study is aimed at providing data about malaria infection, morbidity, and mortality, and MCI in Madagascar.. Two nationwide surveys were simultaneously conducted in 2012-2013 in Madagascar: a study about non-complicated clinical malaria cases in 31 sentinel health facilities, and a cross-sectional survey (CSS) in 62 sites. The CSS encompassed interviews, collection of biological samples and verbal autopsies (VA). Data from CSS were weighted for age, sex, malaria transmission pattern, and population density. VA data were processed with InterVA-4 software.. CSS included 15,746 individuals of all ages. Parasite rate (PR) as measured by rapid diagnostic tests was 3.1%, and was significantly higher in five to 19 year olds, in males, poorer socio-economic status (SES) quintiles and rural areas. Long-lasting insecticidal nets (LLIN) use was 41.7% and was significantly lower in five to 19 year olds, males and wealthier SES quintiles. Proportion of persons covered by indoor residual spraying (IRS) was 66.8% in targeted zones. Proportion of persons using other insecticides than IRS was 22.8%. Coverage of intermittent preventive treatment during pregnancy was 21.5%. Exposure to information, education and communication messages about malaria was significantly higher in wealthier SES for all media but information meetings. The proportion of fever case managements considered as appropriate with regard to malaria was 15.8%. Malaria was attributed as the cause of death in 14.0% of 86 VA, and 50% of these deaths involved persons above the age of five years. The clinical case study included 818 cases of which people above the age of five accounted for 79.7%. In targeted zones, coverage of LLIN and IRS were lower in clinical cases than in general population.. This study provides valuable data for the evaluation of effectiveness and factors affecting MCI. MCI and evaluation surveys should consider the whole population and not only focus on under-fives and pregnant women in pre-elimination or elimination strategies.

Topics: Adolescent; Adult; Communicable Disease Control; Cross-Sectional Studies; Disease Transmission, Infectious; Epidemiological Monitoring; Female; Humans; Madagascar; Malaria; Male; Middle Aged; Pregnancy; Young Adult

Hypoglycemia is a defining feature of severe malaria and several other infectious diseases in children but the prevalence, significance, and prognosis of abnormal blood glucose, including hyperglycemia, have rarely been addressed in severely ill children in non-malaria endemic areas.. In Madagascar, consecutive children (1 month-15 years) admitted to the pediatric ward of a referral hospital, were categorized using the integrated management of childhood illness (IMCI). Samples were taken once on admission for measuring blood glucose concentration. Glycemia levels (hypoglycemia <2.2 mmol/l; low glycemia: 2.2-4.4 mmol/l; normoglycemia >4.4-8.3 mmol/l; and hyperglycemia >8.3 mmol/l) were related to the IMCI algorithm and case fatality. Factors associated with blood glucose concentration and case fatality were analysed using univariate and multivariate analysis.. Of 420 children, 48.1% (n = 202) were severely ill; 3.1% (n = 13) had hypoglycemia; 20.0% (n = 84) low glycemia; 65.9% (n = 277) normoglycemia; and 10.9% (n = 46) hyperglycemia. In univariate analysis, hypoglycemia and hyperglycemia both showed significant increase in the risk of death, as compared to normal blood glucose (RR: 12.2, 95% CI: 6.2-23.7 and RR: 2.5, 95% CI: 1.0-6.2, respectively). Children with low glycemia had no increased risk of death (RR: 1.2, 95% CI: 0.4-3.2) despite a poorer IMCI status on admission. After logistic regression, hypoglycemia (RR: 19.4, 95% CI: 5.0-.74.7, hepatomegaly (RR: 12.2, 95% CI: 3.3-44.9) and coma (RR: 4.8, 95% CI: 1.3-17.6) were the features on admission associated with an increased risk of death.. Dysglycemia in non-neonates is associated with increased mortality. These findings underline the need for the use of rapid screening tests to initiate early treatment. Alternative treatments such as oral or sublingual administration of glucose should be developed in structures with limited resources.

Topics: Blood Glucose; Child; Child, Preschool; Female; Hospital Mortality; Hospitalization; Humans; Hyperglycemia; Hypoglycemia; Infant; Madagascar; Malaria; Male; Patient Outcome Assessment; Prevalence; Referral and Consultation; Risk Factors

Molecular investigations performed following the emergence of sulfadoxine-pyrimethamine (SP) resistance in Plasmodium falciparum have allowed the identification of the dihydrofolate reductase (DHFR) enzyme as the target of pyrimethamine. Although clinical cases of Plasmodium malariae are not usually treated with antifolate therapy, incorrect diagnosis and the high frequency of undetected mixed infections has probably exposed non-P. falciparum parasites to antifolate therapy in many areas. In this context, we aimed to assess the worldwide genetic diversity of the P. malariae dhfr gene in 123 samples collected in Africa and Asia, areas with different histories of SP use. Among the 10 polymorphic sites found, we have observed 7 new mutations (K55E, S58R, S59A, F168S, N194S, D207G, and T221A), which led us to describe 6 new DHFR proteins. All isolates from African countries were classified as wild type, while new mutations and haplotypes were recognized as exclusive to Madagascar (except for the double mutations at nucleotides 341 and 342 [S114N] found in one Cambodian isolate). Among these nonsynonymous mutations, two were likely related to pyrimethamine resistance: S58R (corresponding to C59R in P. falciparum and S58R in Plasmodium vivax; observed in one Malagasy sample) and S114N (corresponding to S108N in P. falciparum and S117N in P. vivax; observed in three Cambodian samples).

Topics: Africa; Animals; Antimalarials; Cambodia; Drug Combinations; Drug Resistance; Genetic Variation; Humans; Madagascar; Malaria; Mutation; Parasitic Sensitivity Tests; Plasmodium malariae; Pyrimethamine; Sequence Analysis, DNA; Sulfadoxine; Tetrahydrofolate Dehydrogenase

Intermittent preventive treatment in infants (IPTi) is a malaria control strategy currently recommended by WHO for implementation at scale in Africa, consisting of administration of sulphadoxine-pyrimethamine (SP) coupled with routine immunizations offered to children under 1 year. In this study, we analysed IPTi acceptability by communities and health staff.. Direct observation, in-depth interviews (IDIs) and focus group discussions (FGDs) were conducted in Benin, Madagascar and Senegal during IPTi pilot implementation. Villages were stratified by immunization coverage. Data were transcribed and analysed using NVivo7 software.. Communities' knowledge of malaria aetiology and diagnosis was good, although generally villagers did not seek treatment at health centres as their first choice. Perceptions and attitudes towards IPTi were very positive among communities and health workers. A misconception that SP was an antipyretic that prevents post-vaccinal fever contributed to IPTi's acceptability. No refusals or negative rumours related to IPTi coupling with immunizations were identified, and IPTi did not negatively influence attitudes towards other malaria control strategies. Healthcare decisions about children, normatively made by the father, are starting to shift to educated and financially independent mothers.. Intermittent preventive treatment in infants is well accepted by providers and communities, showing a synergic acceptability when coupled with routine immunizations. However, a misconception that SP alleviates fever should be addressed when scaling up implementation.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antimalarials; Antipyretics; Attitude of Health Personnel; Bacterial Vaccines; Benin; Community Health Services; Decision Making; Drug Combinations; Female; Health Knowledge, Attitudes, Practice; Humans; Immunization Programs; Infant; Madagascar; Malaria; Male; Measles Vaccine; Middle Aged; Parents; Patient Acceptance of Health Care; Perception; Pyrimethamine; Residence Characteristics; Senegal; Sulfadoxine; Vaccination; World Health Organization; Young Adult

To evaluate the effect of integrating ITN distribution on measles vaccination campaign coverage in Madagascar.. Nationwide cross-sectional survey to estimate measles vaccination coverage, nationally, and in districts with and without ITN integration. To evaluate the effect of ITN integration, propensity score matching was used to create comparable samples in ITN and non-ITN districts. Relative risks (RR) and 95% confidence intervals (CI) were estimated via log-binomial models. Equity ratios, defined as the coverage ratio between the lowest and highest household wealth quintile (Q), were used to assess equity in measles vaccination coverage.. National measles vaccination coverage during the campaign was 66.9% (95% CI 63.0-70.7). Among the propensity score subset, vaccination campaign coverage was higher in ITN districts (70.8%) than non-ITN districts (59.1%) (RR=1.3, 95% CI 1.1-1.6). Among children in the poorest wealth quintile, vaccination coverage was higher in ITN than in non-ITN districts (Q1; RR=2.4, 95% CI 1.2-4.8) and equity for measles vaccination was greater in ITN districts (equity ratio=1.0, 95% CI 0.8-1.3) than in non-ITN districts (equity ratio=0.4, 95% CI 0.2-0.8).. Integration of ITN distribution with a vaccination campaign might improve measles vaccination coverage among the poor, thus providing protection for the most vulnerable and difficult to reach children.

Topics: Bedding and Linens; Child; Child Welfare; Child, Preschool; Cross-Sectional Studies; Delivery of Health Care, Integrated; Female; Health Promotion; Health Status; Humans; Infant; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Mass Vaccination; Measles; Measles Vaccine; Mosquito Control; Poverty; Preventive Health Services; Socioeconomic Factors

Malaria still represents a great cause of death in sub-Saharan African areas, mainly among pregnant women. We conducted this prospective study during two years in a malaria-endemic stable region in the east of Madagascar (Toamasina) with an aim to compare the efficacy of weekly chloroquine (CQ) and the use of intermittent presumptive treatment by sulfadoxine-pyrimethamine (SP). 519 pregnant women were included in this study (CQ = 285; SP = 256). Socio-demographical characteristics of each group were identical. We found more peripheral parasitemia (CQ = 8.07% vs SP = 2.73%; P = 0.0068) and severe malaria in the CQ group (CQ = 1.75% vs SP = 0%; P = 0.0332). Anemia was more frequent in the CQ group (CQ = 4.21% vs SP = 0.35%; P = 0.0038). Placental infestation rate was also higher in the CQ group (CQ = 7.01% vs SP = 0.39%; P = 0.00001). Low birth weight and fetal death were lower in the SP group respectively [(CQ = 4.21% vs SP = 0.78%; P = 0.0121) and (CQ = 1.75%vs SP = 0%; P = 0.0332)].

Topics: Adolescent; Adult; Antimalarials; Chloroquine; Drug Combinations; Endemic Diseases; Female; Humans; Infant, Newborn; Infectious Disease Transmission, Vertical; Madagascar; Malaria; Pregnancy; Pregnancy Complications, Infectious; Prospective Studies; Pyrimethamine; Sulfadoxine

Timing the origin of human malarias has been a focus of great interest. Previous studies on the mitochondrial genome concluded that Plasmodium in primates, including those parasitic to humans, radiated relatively recently during a process where host switches were common. Those investigations, however, assumed constant rate of evolution and tightly bound (fixed) calibration points based on host fossils or host distribution. We investigate the effect of such assumptions using different molecular dating methods. We include parasites from Lemuroidea since their distribution provides an external validation to time estimates allowing us to disregard scenarios that cannot explain their introduction in Madagascar.. We reject the assumption that the Plasmodium mitochondrial genome, as a unit or each gene separately, evolves at a constant rate. Our analyses show that Lemuroidea parasites are a monophyletic group that shares a common ancestor with all Catarrhini malarias except those related to P. falciparum. However, we found no evidence that this group of parasites branched with their hosts early in the evolution of primates. We applied relaxed clock methods and different calibrations points to explore the origin of primate malarias including those found in African apes. We showed that previous studies likely underestimated the origin of malarial parasites in primates.. The use of fossils from the host as absolute calibration and the assumption of a strict clock likely underestimate time when performing molecular dating analyses on malarial parasites. Indeed, by exploring different calibration points, we found that the time for the radiation of primate parasites may have taken place in the Eocene, a time consistent with the radiation of African anthropoids. The radiation of the four human parasite lineages was part of such events. The time frame estimated in this investigation, together with our phylogenetic analyses, made plausible a scenario where gorillas and humans acquired malaria from a Pan lineage.

Topics: Animals; Biological Evolution; Genome, Mitochondrial; Humans; Lemuridae; Madagascar; Malaria; Phylogeny; Plasmodium

In October 2007, Madagascar conducted a nationwide integrated campaign to deliver measles vaccination, mebendazole, and vitamin A to children six months to five years of age. In 59 of the 111 districts, long-lasting insecticidal nets (LLINs) were delivered to children less than five years of age in combination with the other interventions. A community-based, cross-sectional survey assessed LLIN ownership and use six months post-campaign during the rainy season. LLIN ownership was analyzed by wealth quintile to assess equity. In the 59 districts, 76.8% of households possessed at least one LLIN from any source and 56.4% of households possessed a campaign net. Equity of campaign net ownership was evident. Post-campaign, the LLIN use target of > or = 80% by children less than five years of age and a high level of LLIN use (69%) by pregnant women were attained. Targeted LLIN distribution further contributed to total population coverage (60%) through use of campaign nets by all age groups.

Topics: Adult; Child, Preschool; Endemic Diseases; Female; Humans; Infant; Insecticide-Treated Bednets; Madagascar; Malaria; Male; Mosquito Control; Pregnancy

Previous studies, conducted in the urban of Antananarivo, showed low rate of confirmed malaria cases. We used a geographical and environmental approach to investigate the contribution of environmental factors to urban malaria in Antananarivo.. Remote sensing data were used to locate rice fields, which were considered to be the principal mosquito breeding sites. We carried out supervised classification by the maximum likelihood method. Entomological study allowed vector species determination from collected larval and adult mosquitoes. Mosquito infectivity was studied, to assess the risk of transmission, and the type of mosquito breeding site was determined. Epidemiological data were collected from November 2006 to December 2007, from public health centres, to determine malaria incidence. Polymerase chain reaction was carried out on dried blood spots from patients, to detect cases of malaria. Rapid diagnostic tests were used to confirm malaria cases among febrile school children in a school survey.A geographical information system was constructed for data integration. Altitude, temperature, rainfall, population density and rice field surface area were analysed and the effects of these factors on the occurrence of confirmed malaria cases were studied.. Polymerase chain reaction confirmed malaria in 5.1% of the presumed cases. Entomological studies showed An. arabiensis as potential vector. Rice fields remained to be the principal breeding sites. Travel report was considered as related to the occurrence of P. falciparum malaria cases.. Geographical and environmental factors did not show direct relationship with malaria incidence but they seem ensuring suitability of vector development. Absence of relationship may be due to a lack of statistical power. Despite the presence of An. arabiensis, scarce parasitic reservoir and rapid access to health care do not constitute optimal conditions to a threatening malaria transmission. However, imported malaria case is suggestive to sustain the pocket transmission in Antananarivo.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Child; Child, Preschool; Climate; Culicidae; Ecosystem; Female; Geography; Humans; Incidence; Infant; Larva; Madagascar; Malaria; Male; Middle Aged; Parasitology; Polymerase Chain Reaction; Urban Population; Young Adult

Malaria remains a major public health problem in Madagascar, as it is the first cause of morbidity in health care facilities. Its transmission remains poorly documented. An entomological study was carried out over 1 year (October 2003-September 2004) in Saharevo, a village located at an altitude of 900m on the eastern edge of the Malagasy central highlands. Mosquitoes were sampled weekly upon landing on human volunteers and in various resting-places. Out of 5515 mosquitoes collected on humans, 3219 (58.4%) were anophelines. Eleven anopheline species were represented, among which Anopheles funestus, Anopheles gambiae, Anopheles arabiensis and Anopheles mascarensis. Out of 677 mosquitoes collected in bedrooms by pyrethrum spray catches and in Muirhead-Thomson pits, 656 (96.9%) were anopheline belonging to these four latter species. The proportion of mosquitoes that fed on human varied according to the resting-places and the mosquito species: 86% of An. funestus resting in bedrooms fed on humans, whereas only 16% of An. funestus and 0% of An. mascarensis resting in pits fed on humans. The proportion of anopheline mosquitoes infected with human Plasmodium was measured by circumsporozoite protein-ELISA: 10/633 An. funestus (1.58%), 1/211 An. gambiae s.l. (0.48%) and 2/268 An. mascarensis (0.75%). The annual entomological inoculation rate (number of bites of infected anophelines per adult) was estimated at 2.78. The transmission was mainly due to An. funestus and only observed in the second half of the rainy season, from February to May. These results are discussed in the context of the current malaria vector control policy in Madagascar.

Topics: Adult; Animals; Antigens, Protozoan; Biodiversity; Culicidae; Disease Vectors; Enzyme-Linked Immunosorbent Assay; Female; Humans; Madagascar; Malaria; Plasmodium; Seasons

The aim of this study was to provide baseline information of the epidemiological situation of malaria in Madagascar using serological markers. We carried out cross-sectional studies in schoolchildren from eight sites in the four different malarious epidemiological strata of Madagascar. We studied the prevalence of anti-MSP1 antibodies to assess the burden, and anti-CSP antibodies to estimate the transmission intensity, of malaria. The overall prevalence of each antibody tested was 46.1% for anti-PfMSP-1, 15.2% for anti-PvMSP-1, 14.9% for anti-PfCSP, 4.9% for anti-PvCSP and 2.4% for anti-PmCSP. The prevalence of the five antibodies varied significantly between the sites (P<10(-6)). We also found significant effects of ethnic origin on the prevalence of anti-PfMSP1 antibodies. With regular testing in the same target populations, this data will be particularly useful for managing the elimination strategy supported by the Malagasy Government.

Topics: Adolescent; Antibodies, Protozoan; Child; Child, Preschool; Cross-Sectional Studies; Ethnicity; Female; Geography; Humans; Madagascar; Malaria; Male; Merozoite Surface Protein 1; Seroepidemiologic Studies

Madagascar has been known for having bio-geo-ecological diversity which is reflected by a complex malaria epidemiology ranging from hyperendemic to malaria-free areas. Malaria-related attacks and infection are frequently recorded both in children and adults living in areas of low malaria transmission. To integrate this variability in the national malaria control policy, extensive epidemiological studies are required to up-date previous records and adjust strategies.. A longitudinal malaria survey was conducted from July 1996 to June 2005 among an average cohort of 214 villagers in Saharevo, located at 900 m above the sea. Saharevo is a typical eastern foothill site at the junction between a costal wet tropical area (equatorial malaria pattern) and a drier high-altitude area (low malaria transmission).. Passive and active malaria detection revealed that malaria transmission in Saharevo follows an abrupt seasonal variation. Interestingly, malaria was confirmed in 45% (1,271/2,794) of malaria-presumed fevers seen at the health centre. All four Plasmodia that infect humans were also found: Plasmodium falciparum; Plasmodium vivax, Plasmodium malariae and Plasmodium ovale. Half of the malaria-presumed fevers could be confirmed over the season with the highest malaria transmission level, although less than a quarter in lower transmission time, highlighting the importance of diagnosis prior to treatment intake. P. falciparum malaria has been predominant (98%). The high prevalence of P. falciparum malaria affects more particularly under 10 years old children in both symptomatic and asymptomatic contexts. Children between two and four years of age experienced an average of 2.6 malaria attacks with P. falciparum per annum. Moreover, estimated incidence of P. falciparum malaria tends to show that half of the attacks (15 attacks) risk to occur during the first 10 years of life for a 60-year-old adult who would have experienced 32 malaria attacks.. The incidence of malaria decreased slightly with age but remained important among children and adults in Saharevo. These results support that a premunition against malaria is slowly acquired until adolescence. However, this claims for a weak premunition among villagers in Saharevo and by extension in the whole eastern foothill area of Madagascar. While the Malagasy government turns towards malaria elimination plans nowadays, choices and expectations to up-date and adapt malaria control strategies in the foothill areas are discussed in this paper.

Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Animals; Cattle; Child; Child, Preschool; Female; Humans; Incidence; Infant; Infant, Newborn; Longitudinal Studies; Madagascar; Malaria; Male; Middle Aged; Plasmodium falciparum; Plasmodium malariae; Plasmodium ovale; Plasmodium vivax; Rural Population; Seasons; Young Adult

The use of plant repellents against nuisance biting insects is common and its potential for malaria vector control requires evaluation in areas with different level of malaria endemicity. The essential oils of Ocimum suave and Ocimum kilimandscharicum were evaluated against malaria vectors in north-eastern Tanzania.. An ethnobotanical study was conducted at Moshi in Kilimanjaro region north-eastern Tanzania, through interviews, to investigate the range of species of plants used as insect repellents. Also, bioassays were used to evaluate the protective potential of selected plants extracts against mosquitoes.. The plant species mostly used as repellent at night are: fresh or smoke of the leaves of O. suave and O. kilimandscharicum (Lamiaceae), Azadirachta indica (Meliaceae), Eucalyptus globules (Myrtaceae) and Lantana camara (Verbenaceae). The most popular repellents were O. kilimandscharicum (OK) and O. suave (OS) used by 67% out of 120 households interviewed. Bioassay of essential oils of the two Ocimum plants was compared with citronella and DEET to study the repellence and feeding inhibition of untreated and treated arms of volunteers. Using filter papers impregnated with Ocimum extracts, knockdown effects and mortality was investigated on malaria mosquito Anopheles arabiensis and Anopheles gambiae, including a nuisance mosquito, Culex quinquefasciatus. High biting protection (83% to 91%) and feeding inhibition (71.2% to 92.5%) was observed against three species of mosquitoes. Likewise the extracts of Ocimum plants induced KD90 of longer time in mosquitoes than citronella, a standard botanical repellent. Mortality induced by standard dosage of 30 mg/m2 on filter papers, scored after 24 hours was 47.3% for OK and 57% for OS, compared with 67.7% for citronella.. The use of whole plants and their products as insect repellents is common among village communities of north-eastern Tanzania and the results indicate that the use of O. suave and O. kilimandscharicum as a repellent would be beneficial in reducing vector biting. The widespread use of this approach has a potential to complement other control measures.

Topics: Animals; Anopheles; Ethnobotany; Female; Humans; Insect Repellents; Lamiaceae; Malaria; Male; Meliaceae; Mosquito Control; Myrtaceae; Ocimum; Plant Extracts; Plant Leaves; Plant Oils; Tanzania; Verbenaceae

An entomological study was performed to document the transmission of Plasmodium, agents of human malaria in Antananarivo, capital of Madagascar. Human landing mosquitoes were collected at night during two years, between May 2003 and September 2005, in the two sites of Ambohimiandra-Manakambahiny and Ambolokandrina. The genuses of collected mosquitoes were, in order of abundance, Culex, Mansonia and Anopheles. The only potential vector was Anopheles arabiensis. Its maximal abundance was observed in January (22 and 15 bites per man per night, outdoors, respectively in the two sites), during the rainier month of the austral summer This anopheles was biting indoors, in bedrooms, but its agressivity was always higher outdoors than indoors. Its maximal agressivity was observed indoors between 00 and 01 am. The absence of An. gambiae and An. funestus in the catches on the one hand, and the absence of An. arabiensis infected by Plasmodium falciparum on the other hand, are discussed.

Topics: Animals; Anopheles; Biodiversity; Ecology; Ecosystem; Humans; Madagascar; Malaria; Plasmodium; Urban Population

Rapid diagnostic tests (RDTs) are becoming increasingly indispensable in malaria management, as a means of increasing the accuracy of diagnosis. The WHO has issued recommendations, but the selection of the most suitable RDT remains difficult for users in endemic countries. The genetic variability of the antigens detected with RDTs has been little studied, but may affect the sensitivity of RDTs. This factor has been studied by comparisons between countries at continental level, but little information is available concerning antigen variability within a given country.. A country-wide assessment of polymorphism of the PfHRP2, PfHRP3, pLDH and aldolase antigens was carried out in 260 Plasmodium falciparum and 127 Plasmodium vivax isolates, by sequencing the genes encoding these antigens in parasites originating from the various epidemiological strata for malaria in Madagascar.. Higher levels of polymorphism were observed for the pfhrp2 and pfhrp3 genes than for the P. falciparum and P. vivax aldolase and pldh genes. Pfhrp2 sequence analysis predicted that 9% of Malagasy isolates would not be detected at parasite densities < or = 250 parasites/mul (ranging from 6% in the north to 14% in the south), although RDTs based on PfHRP2 detection are now recommended in Madagascar.. These findings highlight the importance of training of health workers and the end users of RDTs in the provision of information about the possibility of false-negative results for patients with clinical symptoms of malaria, particularly in the south of Madagascar.

Topics: Animals; Antigens, Protozoan; DNA, Protozoan; False Negative Reactions; Humans; Madagascar; Malaria; Molecular Sequence Data; Plasmodium falciparum; Plasmodium vivax; Polymorphism, Genetic; Protozoan Proteins; Reagent Kits, Diagnostic; Sensitivity and Specificity; Sequence Analysis, DNA

The main purpose of this study was to assess the accuracy of various techniques available for diagnosis of malaria. Blood samples were collected from 313 patients with clinical suspicion of uncomplicated malaria in 2 primary health centers in Madagascar. The presence of Plasmodium parasites was assessed by conventional microscopy, 2 rapid diagnostic tests (one HRP2-based test, PALUTOP(+4), and one pLDH-based test, OptiMAL-IT), and real-time polymerase chain reaction (PCR), which is used as the "gold standard" method. The degree of agreement observed was very high for microscopy (0.99) and the HRP2-based test (0.93) and high for the pLDH-based test (0.82). Public-health implications are also discussed in this paper.

Topics: Adolescent; Adult; Aged; Animals; Antigens, Protozoan; Child; Child, Preschool; Endemic Diseases; Female; Fever; Humans; Immunoassay; Infant; Madagascar; Malaria; Male; Microscopy; Middle Aged; Parasitemia; Plasmodium; Predictive Value of Tests; Reproducibility of Results

The Atelier Paludisme (Malaria Workshop) is an international training course organized by the Institut Pasteur de Madagascar, which has been held annually for the past five years. The course was designed for both young and experienced researchers, as well as for healthcare professionals, mostly from malaria-endemic countries. Its objective is to provide participants with a broad knowledge of all features of malaria, to improve their skills in project management, to break geographical isolation by using the Internet as a source of documentary information. This six-week course makes use of concepts of andragogy and problem-based learning, i.e. a relationship between participants and tutors, which promotes a process of exchange rather than the simple transmission of knowledge, where participants have to search actively for information. This approach to training, combined with the wide background and experience of those involved, creates positive dynamics and enables participants to acquire new skills, develop their critical and analytical abilities. This paper describes the course and the lessons learned from its evaluation.

Topics: Curriculum; Health Personnel; Humans; Internationality; Madagascar; Malaria; Problem-Based Learning; Program Evaluation; Role Playing

The highlands of Madagascar present an unstable transmission pattern of malaria. The population has no immunity, and the central highlands have been the sites of epidemics with particularly high fatality. The most recent epidemic occurred in the 1980s, and caused about 30,000 deaths. The fight against malaria epidemics in the highlands has been based on indoor insecticide spraying to control malaria vectors. Any preventive programme involving generalised cover in the highlands will require very substantial logistical support. We used multicriteria evaluation, by the method of weighted linear combination, as basis for improved targeting of actions by determining priority zones for intervention.. Image analysis and field validation showed the accuracy of mapping rice fields to be between 82.3% and 100%, and the Kappa coefficient was 0.86 to 0.99.A significant positive correlation was observed between the abundance of the vector Anopheles funestus and temperature; the correlation coefficient was 0.599 (p < 0.001). A significant negative correlation was observed between vector abundance and human population density: the correlation coefficient was -0.551 (p < 0.003). Factor weights were determined by pair-wise comparison and the consistency ratio was 0.04. Risk maps of the six study zones were obtained according to a gradient of risk. Nine of thirteen results of alert confirmed by the Epidemiological Surveillance Post were in concordance with the risk map.. This study is particularly valuable for the management of vector control programmes, and particularly the reduction of the vector population with a view to preventing disease. The risk map obtained can be used to identify priority zones for the management of resources, and also help avoid systematic and generalised spraying throughout the highlands: such spraying is particularly difficult and expensive. The accuracy of the mapping, both as concerns time and space, is dependent on the availability of data. Continuous monitoring of malaria transmission factors must be undertaken to detect any changes. A regular case notification allows risk map to be verified. These actions should therefore be implemented so that risk maps can be satisfactorily assessed.

Topics: Animals; Anopheles; Crops, Agricultural; Decision Support Techniques; Humans; Insect Vectors; Insecticides; Madagascar; Malaria; Mosquito Control; Oryza; Risk Factors; Topography, Medical

The Malaria Workshop organized by Institut Pasteur de Madagascar is an original course that applies innovative concepts to training of health professionals involved in malaria control in endemic countries. Course objectives are to enhance the skills needed to fight malaria (transversal competencies, critical approach, and position statement), to reinforce project cycle management proficiency, and to demonstrate how the Internet can be used as a source of documentation to compensate for geographical isolation. The Malaria Workshop is a six-consecutive-week full-day course that has been presented once a year since 2003. Seventy-six researchers, physicians or health ministry officials have already benefited from this training. Teaching methods emphasize andragogy that facilitates a learner/mentor relationship promoting exchange rather than transmission of knowledge and problem-based learning that engages learners to take an active part in gathering information. These methods in combination with the diverse backgrounds and experience of course participants foster a positive dynamic environment for learning that is monitored by weekly progress evaluation. Follow-up surveys have confirmed the positive effect of this training on the professional performance of former participants who become more involved in program development and fund-raising efforts. A professional network is growing and learners are starting to their experience. In this report workshop organizers describe the course's origins and concepts and present the conclusions drawn based on the first five yearly sessions.

Topics: Curriculum; Endemic Diseases; Health Personnel; Humans; Madagascar; Malaria; Problem-Based Learning

The study of urban malaria is an area undergoing rapid expansion, after many years of neglect. The problem of over-diagnosis of malaria, especially in low transmission settings including urban areas, is also receiving deserved attention. The primary objective of the present study was to assess the frequency of malaria among febrile outpatients seen in private and public primary care facilities of Antananarivo. The second aim was to determine, among the diagnosed malaria cases, the contribution of autochthonous urban malaria.. Two cross-sectional surveys in 43 health centres in Antananarivo in February 2003 (rainy season) and in July 2003 (dry season) were conducted. Consenting clinically suspected malaria patients with fever or history of fever in the past 48 hours were included. Malaria rapid diagnostic tests and microscopy were used to diagnose malaria. Basic information was collected from patients to try to identify the origin of the infection: autochthonous or introduced.. In February, among 771 patients, 15 (1.9%) positive cases were detected. Three malaria parasites were implicated: Plasmodium. falciparum (n = 12), Plasmodium vivax (n = 2) and Plasmodium. ovale (n = 1). Only two cases, both P. falciparum, were likely to have been autochthonous (0.26%). In July, among 739 blood smears examined, 11 (1.5%) were positive: P. falciparum (n = 9) and P. vivax (n = 2). Three cases of P. falciparum malaria were considered to be of local origin (0.4%).. This study demonstrates that malaria cases among febrile episodes are low in Antananarivo and autochthonous malaria cases exist but are rare.

Topics: Animals; Anopheles; Antigens, Protozoan; Child, Preschool; Cross-Sectional Studies; Female; Fever; Humans; Madagascar; Malaria; Malaria, Falciparum; Male; Plasmodium falciparum; Plasmodium ovale; Plasmodium vivax; Polymerase Chain Reaction; Prevalence; Protozoan Proteins; Seasons; Urban Population

Malaria transmission remains poorly documented in areas of low transmission. A study has been carried out over two consecutive years in Analamiranga, a village located at an altitude of 885m on the western edge of the Malagasy highlands, with the aim of generating and updating malariometric indexes for both mosquitoes and schoolchildren. In this village, no vector control measures were performed during the study period nor during previous decades. Mosquitoes were collected monthly when landing on human volunteers and in various resting-places. Blood samples were taken every 3 months from schoolchildren aged 6-12 years and microscopically examined. Of 7,480 mosquitoes collected on human subjects, 5,790 were anophelines. Ten anopheline species were represented and three of these, Anopheles funestus, Anopheles arabiensis and Anopheles mascarensis, accounted for 59.2% of the collection. Of these three species 4,640 were also collected in resting places. The proportion of mosquitoes fed on bovids was high; conversely, the anthropophilic rate (mosquitoes fed on human beings) was especially low: 31%, 7% and 1%, respectively, for A. funestus, A. arabiensis and A. mascarensis. The only confirmed malaria vector was A. funestus with a low sporozoite index (of 6,830 A. funestus, five were positive for Plasmodium falciparum and four for Plasmodium vivax). The annual entomological inoculation rate (number of bites of infected anophelines per adult person) was estimated at 2.49 with low variation over the 2 years. Overall, 909 thick blood smears were tested from blood samples taken from schoolchildren with 30.3% being malaria-positive. The four Plasmodium species infecting human subjects were detected in the following proportions: P. falciparum 78.9%, P. vivax 19.4%, Plasmodium malariae 1.0% and Plasmodium ovale 0.7%. The proportions of children who were infected with any Plasmodium ranged from 10.7% in February to 51.0% in September. Parasitemic children with fever (axillary temperature >37.5 degrees C) accounted for 16.4% of the children sampled. This study demonstrates that there are substantial parasitological consequences of even a relatively low entomological transmission and also recommends including exterior resting-places of mosquitoes in future spraying campaigns in the highlands of Madagascar.

Topics: Animals; Anopheles; Child; Female; Humans; Insect Vectors; Madagascar; Malaria; Malaria, Falciparum; Malaria, Vivax; Population Density; Prevalence; Rural Health; Seasons; Time Factors

Anopheles gambiae s.s. Giles (Diptera: Culicidae), the primary African malaria vector, has been characterized at the subspecies level in Madagascar, where only the molecular form S and haplotype gIA occur. The haplotype gIC proposed by other authors was not observed amongst the 35 mosquito genomes sequenced. These S/gIA characteristics are also found on the Comoros archipelago and in continental Africa.

Topics: Animals; Anopheles; DNA, Ribosomal Spacer; Female; Haplotypes; Insect Vectors; Madagascar; Malaria

Malaria diagnosis is part of the daily activities of the Clinical Biology Center (CBC) of the Institut Pasteur de Madagascar in Antananarivo. Over a period of four years (2001-2004), regardless the methods being used, out of 6537 blood samples examined, 159 (2.43%) tests were positive. All four species of Plasmodium infecting human. were detected with a high prevalence of P. falciparum (87.2%). 49/159 patients were foreigners, but their files did not allow us to distinguish imported from locally acquired malaria cases. Also, among Malagasy patients, there was no possibility to recognize introduced malaria cases (contracted in coastal areas). In Madagascar malaria remains a public health problem. But fever and recent history of fever are often considered and treated as malaria. Our results demonstrated that confirmed malaria rate was very low. Reporting malaria on the basis of clinical signs overestimates malaria cases at the national level. The importance of malaria biological diagnosis is discussed in this article.

Topics: Humans; Madagascar; Malaria; Retrospective Studies; Urban Population

A 4-year entomological study was carried out in Southern Madagascar to identify malaria vectors, evaluate the transmission and compare the influence of irrigation in the sub-arid and adjacent humid regions. Three villages were involved in this entomological survey: Androvasoa (located in the natural sub-arid ecosystem), Pépiniére (sited at the centre of an irrigated rice scheme in the sub-arid region) and Esana (bordered with rice fields in the humid region). Mosquitoes were collected inside and outside dwellings when landing on human beings, with light traps and with knockdown indoor sprays. Anopheles arabiensis, Anopheles merus and Anopheles funestus were found in every village while Anopheles gambiae s.s. was only found in the village bordering the rice-fields (Pépiniére) and Anopheles mascarensis, a mosquito native to Madagascar, was only found in the humid region (Esana). In Pépiniére, the annual entomological inoculation rate (EIR) was low (EIR=0.4 infective bites/man/year (IBM)). In the irrigated scheme of the sub-arid region, malaria transmission was 150 times higher (mean EIR=63 IBM) than in the natural ecosystem and A. funestus was the main vector, responsible for 90% of infective bites. In Esana, the level of malaria transmission was high (EIR=41 IBM) and 2/3 of the infective bites were due to A. mascarensis, despite the presence of A. gambiae s.s. and A. funestus. These results are discussed with reference to the impact of irrigation on malaria in Africa ("the paddies paradox").

Topics: Animals; Anopheles; Crops, Agricultural; Ecosystem; Insect Vectors; Madagascar; Malaria; Mosquito Control; Oryza; Population Density; Seasons; Water Supply

The anopheline vectors and malaria transmission were investigated in the Middle West of Madagascar, in the village of Ambohimena (at the altitude of 940 meters) during two years (August 1996 to July 1998). This village is located outside the vector control area, where yearly DDT house spraying campaigns have been conducted between 1993 and 1998. Collection of mosquitoes was mainly based on all night man billing collections (650 man-nights), pyrethrum spray catches (224 bedrooms) and direct collections in outdoor resting places (140 toilets, 61 pigsties, 33 holes, 19 sheds, 79 sisal hedges, 70 cart shelters). Blood fed anophelines allowed analysis of the origin of blood with an ELISA method. Presence of circum-sporozoite protein was assessed with another ELISA method. The total number of collected anophelines was 14,280. Two malaria vectors were identified: Anopheles funestus Giles, 1900 and An. arabiensis Patton, 1902. An. funestus was the most abundant mosquito, especially during the hot rainy season. Two peaks of abundance were observed (in December and April). Endophagic rate (for mosquitoes aggressive for man) of 35.3%, an endophilic rate (for resting mosquitoes) of 78.0% and an anthropophilic rate (for indoor resting mosquitoes) of 64.0% were calculated. The average parity rate was relatively low (61.2%). The Plasmodium falciparum immunological sporozoite rate was 0.20%. An. funestus presented a higher vectorial capacity during the first round of rice cultivation (January) than during the second round (April-May). An. arabiensis was mostly abundant in December and January at the beginning of the rainy season. This species was exophagic (endophagic rate = 27.5%) and zoophilic (anthropophilic rate = 7.8%). The sporozoitic index was determined as zero (number of examined mosquitoes = 871). In this village, An. arabiensis presented only marginal importance for malaria transmission. Malaria transmission occurred from December to April. Annual entomological inoculation rate, only due to An. funestus, was 8.96 during the first year, and 3.17 during the second year. In this area where transmission is moderately stable, we suggest an extension of vector imagocidal control activities up to the western fringes of the Highlands.

Topics: Animals; Anopheles; Ecosystem; Humans; Insect Bites and Stings; Insect Vectors; Madagascar; Malaria; Oryza; Seasons

The clinical efficacy of chloroquine was assessed in the Primary Health Centre of Ankazobe, Central Highlands of Madagascar. This study shows an increase in the level of chloroquine resistance with the appearance of early treatment failures and RIII resistance. Furthermore, the prevalence of clinical treatment failures is approaching the level of 25%, at which WHO recommends a change of first-line drug.

Topics: Adolescent; Adult; Antimalarials; Child; Child, Preschool; Chloroquine; Drug Resistance; Female; Follow-Up Studies; Humans; Madagascar; Malaria; Male; Middle Aged; Treatment Failure

Malaria is influenced by a web of individual and ecological factors, i.e. factors relating to people and relating to environment. For a long time analysing these factors concurrently has raised statistical problems. Multilevel modelling provides a new attractive solution, which is still uncommon in tropical medicine.. Using an actual data set of 3864 individuals from 38 villages of the Highland Madagascar, a two-level modelling process is presented. Individual malaria parasitaemia is modelled step by step according to age (individual factor), altitude, and DDT indoor house-spraying status (village factors).. The hierarchical organization of a data set in levels, fixed and random effects, and cross-level interactions are considered. Accurate estimations of standard errors, impact of unknown or unmeasured variables quantified and accounted for through random effects, are the highlighted advantages of multilevel modelling.. While not denying the importance of understanding an aetiological chain, the authors recommend an increased use of multilevel modelling, mainly to identify accurately ecological targets for public health policy.

Topics: Adolescent; Adult; Altitude; Antiparasitic Agents; Child; Cross-Sectional Studies; DDT; Disease Outbreaks; Humans; Madagascar; Malaria; Middle Aged; Models, Statistical; Public Health Practice; Seasons

The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani--the dog--has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar). Migrants coming from Africa and Arabia brought with them the two African forms of bilharziosis: S. haematobium and S. mansoni.

Topics: Africa; Animals; Disease Reservoirs; Echinococcosis; Elephantiasis, Filarial; Emigration and Immigration; Europe; History, Ancient; Humans; Insect Vectors; Leishmaniasis; Madagascar; Malaria; Parasitic Diseases; Schistosomiasis

To evaluate the determining factors of the malaria transmission in the northwest region of Madagascar, transversal studies were carried out through one year, from March 1997 to April 1998, in two villages located near Mandritsara, at less than 300 meters above sea level. The rice-growing region forms an intermediate zone between the central highlands with epidemic and instable malaria and the coastal zone with endemic and stable malaria. Mosquitoes were collected when landing on humans during the night and by pyrethrum spray catches as regards endophilic mosquitoes. Three vectors were identified: Anopheles arabiensis, An. gambiae and An. funestus. An. arabiensis and An. gambiae were exophagic and zoophilic. An. funestus was endo-exophagic and anthropophilic but this species shows also a zoophilic trophic deviation. In both villages, An. funestus is the main vector of human malaria. Malaria transmission was estimated to be around 50 and 70 infective bites/person/year in each village.

Topics: Altitude; Animals; Anopheles; Ecosystem; Ethology; Humans; Insect Bites and Stings; Insect Vectors; Madagascar; Malaria; Oryza

Anopheles mascarensis has been demonstrated to be a vector of human malaria in the East coast of Madagascar. Here, we present original data obtained from 1996 to 2003 on the distribution, biology and vectorial capacity of An. mascarensis in the Middle-West of Madagascar. This species is consistently exophilic both for its trophic and resting behaviour. This accounts for the absence of clear impact of any indoor insecticide spraying. This species is mainly zoophilic, but can occasionally bite humans, which explains a low sporozoitic index (1/2218 = 0.045%). The densities of human landing mosquitoes are most of the time very low, with the exception of a peak between May and August at the beginning of the dry season. It implies that the vector's efficiency is very low but not insignificant in the Middle-West of Madagascar, a situation opposite to what is observed on the East coast. The vectorial efficiency of An. mascarensis and An. arabiensis would enable to maintain a low malarial endemicity in the Middle-West, even in the complete absence of An. funestus.

Topics: Altitude; Animals; Anopheles; Climate; Endemic Diseases; Enzyme-Linked Immunosorbent Assay; Feeding Behavior; Humans; Insect Vectors; Longevity; Longitudinal Studies; Madagascar; Malaria; Mosquito Control; Population Density; Population Surveillance; Residence Characteristics; Seasons

Madagascar is a tropical island affected by many natural disasters. The eastern coastal zone--an area of perennial malaria transmission--is regularly exposed to cyclones. Few malaria studies have been done in this area of Madagascar, and none have examined the potential relationship between malaria and natural disasters. A mobile team spent six weeks in the fields doing three lines of research: an entomological study by catching mosquitoes and determining their species: a therapeutic study of chloroquine (CQ) and sulphadoxine-pyrimethamine (SP) according to a 14 days WHO protocol and also a study of physician's diagnostic ability. Physicians were asked to make a presumptive clinical diagnosis of all febrile patients, and these results were compared to those obtained from blood smear examinations. The entomological study found three major vectors species: Anopheles gambiae, An. funestus and An. mascarensis. The therapeutic study showed that SP was 100% effective (n = 13) and only one case of CQ treatment failure was recorded (1/15). Finally the diagnostic study demonstrated that presumptive diagnosis of malaria based on the only clinical signs leads to an over-estimation of malaria frequency. Over 68% (102/149) of febrile patients were diagnosed by physicians to have malaria while only 52 (34.9%) were proven positive. Of the 47 patients diagnosed clinically as malaria-negative, 12 (25.5%) turned out to be positive. Outbreaks of malaria during or after natural disasters in Madagascar can be successfully treated with either CQ or SP, but compliance may be better with SP since it requires only one dose. Perhaps equally important in the context of natural disasters is to have the capacity to make a definitive diagnosis, and the dipsticks should be made available.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Anopheles; Antimalarials; Child; Child, Preschool; Chloroquine; Cross-Sectional Studies; Disasters; Drug Combinations; Female; Humans; Infant; Infant, Newborn; Insect Vectors; Madagascar; Malaria; Male; Middle Aged; Mosquito Control; Parasitic Sensitivity Tests; Population Density; Population Surveillance; Prevalence; Pyrimethamine; Risk Factors; Seasons; Sulfadoxine; Surveys and Questionnaires; Treatment Outcome

This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds, belonging to 43 species sampled at six localities in different bio-climatic zones of the island, 139 (35.9%) showed at least 1 hemoparasite with, by order of frequency, Plasmodium and/or Haemoproteus (19.9%), microfilariae (13.7% of 387 birds), Leucocytozoon (11.1%) and Trypanosoma (1.0%). An analysis to further elucidate these observations took into account the interaction of different environmental variables (altitude, season, site of collection) or aspects of the birds (age, weight, sex). There is evidence that some parasites preferentially infect some bird species or families. The largest male birds harboured the highest prevalences and densities of haemoparasite, regardless of species. These findings extend knowledge of bird/blood parasite relationships of Malagasy birds and provide interesting insights, especially concerning the pathogenicity of this type of parasitism and the parasite transmission by insect vectors.

Topics: Age Distribution; Altitude; Animals; Animals, Wild; Bird Diseases; Body Weight; Climate; Helminthiasis, Animal; Madagascar; Malaria; Male; Parasitic Diseases, Animal; Population Surveillance; Prevalence; Seasons; Sex Distribution; Trypanosomiasis

Malaria transmission in Madagascar is highly variable from one region to the next, and the consequences of the disease on pregnant women and their foetuses are not fully documented. In midwestern Madagascar, the high-transmission lowlands in the west of the country meet the central plateaux, where malaria is unstable because of the high altitude and annual indoor spraying of DDT since 1993. We studied five of the region's main maternity clinics. We began by interviewing sample groups of women of childbearing age living within the vicinity of each clinic. This enabled us to determine the extent to which they had accessed and made use of available maternal health services during pregnancy and delivery, and, hence, to estimate the feasibility of boosting the prophylaxis. We then spent a whole year (from June 1996 to May 1997) observing deliveries at the five clinics in order to gauge the prevalence of placental infection and its consequences on birthweight in various transmission situations. Although only between 2 and 15% of the women said that they had taken prophylaxis during their previous pregnancy, the vast majority had benefited from preventive care: 97% had attended an antenatal visit on at least one occasion and 84% had had the assistance of medical or paramedical staff during delivery, even when their homes were situated relatively far away from the clinic (76%). In total, we observed 1637 deliveries with a mean placental malaria prevalence rate of 8.1%. Individual prevalence rates, however, were found to differ significantly between the maternity clinics situated in the east (minimum 2.1%) and west (maximum 26.2%) of the region. There were also marked variations in line with the seasonal fluctuations in entomological transmission. On the whole, a greater percentage of low birthweights (LBWs) was recorded at the lowland clinics than at the highland ones (17.1% vs. 9.7%), possibly because of the higher malaria infection rate in low altitude areas. On the other hand, the relative risk of LBW linked to placental infection was far greater in the highlands [4.9 (3.3-7.3)] than in the lowlands [1.9 (1.2-3.0)]. Although the rate of placental malaria among women inhabiting the country's central plateaux may be low, it means that transmission--and, hence, the risk of LBW because of placental infection--still persists in spite of the indoor DDT spraying programme. For maximum efficacy, we recommend a combination of vector control (extended to lower altitude

Topics: Altitude; Birth Weight; Comorbidity; Environmental Monitoring; Epidemiological Monitoring; Female; Geography; Humans; Infant, Low Birth Weight; Infant, Newborn; Interviews as Topic; Logistic Models; Madagascar; Malaria; Placenta; Pregnancy; Pregnancy Complications, Parasitic; Prenatal Care; Prevalence; Preventive Medicine; Risk

The central highlands in Madagascar are characterized by an unstable occurrence of malaria with the risk of sporadic outbreaks. In major parts of the region DDT indoor spraying campaigns have been carried out from 1993 to 1998. This strategy was in 1999 replaced by another anti-vector intervention program targeting residual foci as detected by a surveillance and early warning system. This system is based on monitoring of presumptive malaria cases in the communities by which the number of presumptive cases exceeded a defined warning threshold value per month. The system was in the follow-up period shown to be very sensitive to variation of the coverage of anti-vector interventions: the number of presumptive cases decreased in the villages in which indoor spraying had been carried out and a minor increase was observed in those villages, where indoor spraying has been suspended. An increase of malaria cases was observed in 44 (20.8%) out of 212 study sites in the same period. The increase was in particular predominant in areas at lower attitude at the outer zones of the central highlands.

Topics: Altitude; Animals; DDT; Disease Outbreaks; Housing; Humans; Incidence; Madagascar; Malaria; Mosquito Control; Program Evaluation; Risk Factors; Seasons; Sensitivity and Specificity

Following the severe malaria outbreak in the central highlands in Madagascar in 1986, a vector control program by use DDT pm 75 house-spraying has been implemented to operate in areas located at altitudes between 1000 and 1500 m. Early treatment with chloroquine has also been incorporated in the control program. To detect areas at particular high risk for malaria outbreak the Geographic Information System (GIS) has been applied and tested. The study has shown that the system can be used in malaria surveillance in order to identify areas in which an intense distribution of Anopheles funestus can be anticipated and, hence, targeted in spraying campaigns. The system may also be used to monitor changes in anti-malarial drug resistance, in addition, to control of other vector-born diseases.

Topics: Altitude; Animals; Anopheles; Antimalarials; Chloroquine; DDT; Disease Outbreaks; Drug Resistance; Endemic Diseases; Geographic Information Systems; Housing; Humans; Insect Vectors; Madagascar; Malaria; Mosquito Control; Population Surveillance; Risk Factors; Seasons

Topics: Aspirin; Cause of Death; Child; Developing Countries; Female; Health Promotion; Humans; Madagascar; Malaria; Male; Nitric Oxide; Reye Syndrome

For malaria vector control in Madagascar, the efficacy of lambda-cyhalothrin 10% wettable powder (ICON 10 WP) was compared with DDT 75% WP for house-spraying. This evaluation was conducted from November 1997 to September 1998 in highland villages of Vakinankaratra Region, at the fringe of the malaria epidemic zone, outside the zone covered by routine DDT house-spraying (Opération de pulvérisation intro-domiciliaire de DDT: OPID zone). Treatments were compared by house-spraying in four areas: 1) application of DDT 2g ai/m2 and 2) lambda-cyhalothrin 30 mg ai/m2 in previously unsprayed villages; 3) no intervention (control); 4) OPID 5th cycle of DDT 2g ai/m2. The prevalent vector Anopheles funestus almost disappeared from both the DDT and ICON sprayed areas, whereas in the unsprayed (control) area An. funeslus density went up to 60 females per room in April and there were two seasonal peaks of malaria transmission in January and March (see following paper). In the area sprayed with ICON, the parous rate of An. funestus decreased from 47% pre-spray to 39% six months post-spraying, while the parous rate increased in DDT-sprayed area (from 57% pre-spray to 64% six months post-spray). Bioassays of An. funestus on treated walls, six months post-spray, gave mortality rates of 100% on DDT and 90% on ICON. Conversely, ICON appeared to be more effective than DDT on thatched roofs (66% versus 100%, respectively, six months post-spray). In areas sprayed with DDT or ICON the density of An. arabiensis were little affected. This study demonstrated that, under equivalent conditions, both DDT and lambda-cyhalothrin were effective in reducing malaria transmission on the western fringes of the malaria epidemic zone of the malagasy highlands, with a residual effect lasting at least for six months. Lambda-cyhalothrin appeared to be more effective than DDT in reducing the longevity of malaria vectors. In addition to efficacy, the choice of insecticide for malaria vector control should take into account their acceptability by human populations and their toxicity and persistence in the environment.

Topics: Aerosols; Animals; Anopheles; DDT; Female; Housing; Humans; Insect Vectors; Insecticides; Longevity; Madagascar; Malaria; Male; Mosquito Control; Nitriles; Pyrethrins; Seasons; Time Factors

For malaria vector control in Madagascar, 10 WP (lambda-cyhalothrin 10% wettable powder) was compared with DDT 75% WP for house-spraying, from November 1997 to September 1998. This study was implemented at the fringe of the malaria epidemic zone, in villages on western slopes of the central highlands, outside the area covered for the past five years by routine DDT house-spraying (OPID). Four types of treatment were compared in different areas: 1) DDT 2 g ai/m2 and 2) lambda-cyhalothrin 30 mg ai/m2 in previously unsprayed villages, 3) no intervention (control); 4) yearly DDT spraying (OPID fifth cycle). To investigate the malariological impact of spraying, cross-sectional surveys of the village populations were performed in each study area at intervals of two months, before and after spraying. In the newly sprayed areas, from December to June, malaria indices decreased by 62% in the ICON area and 44% in the DDT area, whereas in the unsprayed village malaria increased by 32% during the same season. There was a similar decrease in the number of gametocyte carriers in the newly sprayed areas. Active malaria case detection among febrile individuals was performed fortnightly in each village outside the OPID area. Results showed decreased malaria incidence from February (two months post-spraying) in the sprayed villages, despite the rainy season, whereas in the unsprayed area the decline occurred only after the main transmission season. This study demonstrated that, parasitologically as well as entomologically, house-spraying with residual insecticide (DDT or ICON) was an effective method for controlling malaria on the western fringes of the Madagascar highlands epidemic zone. Both products were effective, but ICON had slightly better impact than DDT, i.e. more reduction of malaria indices and of vector longevity, less irritancy of mosquitoes. For best results in this area of transition between stable and unstable malaria, we recommend earlier annual spraying (as soon as November) and extension of the OPID barrier towards western and northern slopes of the Plateau.

Topics: Adolescent; Aerosols; Animals; Anopheles; Child; Child, Preschool; Cross-Sectional Studies; DDT; Female; Housing; Humans; Infant; Insect Vectors; Insecticides; Longevity; Madagascar; Malaria; Male; Mosquito Control; Nitriles; Pyrethrins; Risk Factors; Seasons; Time Factors

Burkitt lymphoma (LB), a frequent, very progressive cancer with multiple factors, can be cured. However, the mortality rate remains high in Madagascar.. To analyse the epidemiological aspects of LB as well as related socio-economical issues in order to improve successful treatment of the disease.. Retrospective study of files for children aged under 15 years, hospitalised for LB in the Antananarivo oncology unit from October 1985 to June 2000. The inclusion criteria were anatomo-pathological, clinical and/or X-ray results. Studied parameters included age, sex, ethnic group, medical history, and the distance covered by the child before his/her hospitalisation.. The 77 cases of LB represented 16% of all children aged under 15 years seen in the hospital. The characteristics of the cases corresponded to those of African endemic LB. Most of the children with LB came from areas with endemic malaria, the Eastern and the Centre of Madagascar. All of them belonged to underprivileged families. Early medical advice was sought but distance from services delayed treatment. Various units referred the children, but especially oral surgeons (stomatologists) and ORL physicians.. A strategy to ensure rapid treatment for children suffering from LB should be developed, from their region of origin up until treatment. This should involve parents as well as all members of the medical staff in charge of these children.

Topics: Adolescent; Burkitt Lymphoma; Child; Child, Preschool; Endemic Diseases; Female; Humans; Infant; Infant, Newborn; Madagascar; Malaria; Male; Retrospective Studies; Socioeconomic Factors

The definition of severe malaria is no longer limited to cerebral malaria, but it is as well extended to other clinical forms of the disease. The authors reported the epidemiological and clinical survey and evaluative aspects of severe malaria in Antananarivo. This retrospective study included 48 children less than 15 years old, hospitalized at the paediatric unit Debré of the Centre Hospitalier Universitaire de Befelatanana (Antananarivo) for severe malaria as defined by world Health Organization (WHO) criteria. The hospitalization frequency was 0.87%. Higher frequency was noticed for the children less than 5 years old, the sex-ratio was 1.4/1. The cerebral complications as seen in many African countries were the most frequent clinical form. The death rate was 14.58% and the proportional mortality was 1.07%, 2.1% of the patients had sequel. The improvement of severe malaria prognosis was not only on better equipment in intensive care wards, but also on improved and early diagnosis and management.

Topics: Adolescent; Age Distribution; Cause of Death; Child; Child, Preschool; Female; Hospital Mortality; Hospitalization; Hospitals, General; Humans; Infant; Intensive Care Units, Pediatric; Madagascar; Malaria; Malaria, Cerebral; Male; Prognosis; Retrospective Studies; Seasons; Severity of Illness Index; Sex Distribution; Treatment Outcome

In 1991, Anopheles gambiae and Anopheles funestus, the main malaria vectors in the Highlands of Madagascar, were reported to be fully susceptible to DDT; nevertheless a slight decrease in the susceptibility levels was recorded when compared with previous assays carried out in 1962. From 1993 to 1997, five cycles of indoor residual spraying have been carried out in the Highlands: a total of 1,482,000 kg of 70% wp DDT have been used for the treatment of houses and animal shelters. From 1996 to 1999, adult mosquito susceptibility tests to DDT and to some pyrethroids (lambdacyalothrine, deltamethrine, permethrine and cyfluthrine) have been carried out on samples collected in 20 areas of the Highlands. Bioassays were carried out following the WHO standard method. All tested populations of An. funestus showed a full susceptibility to DDT. An. gambiae showed a widespread decrease in the susceptibility to DDT, particularly marked in the region of the capital city Antananarivo. Both species were susceptible to pyrethroids.

Topics: Adult; Altitude; Animals; Anopheles; Biological Assay; DDT; Female; Housing; Housing, Animal; Humans; Insect Vectors; Insecticide Resistance; Insecticides; Madagascar; Malaria; Mosquito Control; Pyrethrins

A retrospective study was conducted to assess mortality rates at the Befelatanana Women's Hospital from January 1st 1988 through December 31st 1997, define trends, study causes and identify problems encountered during treatment and those related to the referral system, in order to improve prevention and patient management. and method. Birth and death registries, operation reports and patient charts were analyzed. All maternal deaths wether of direct or indirect obstetrical origin were considered.. There were 997 cases of maternal death among 91, 032 births, i.e. 1.09% or 1,245 maternal deaths per 100,000 live births. Among direct obstetrical causes of death (93%), 65.8% involved infectious complications and 22.9% renal and vascular complications.Other causes were anesthesia accidents and thrombolic events. Among the direct obstetrical causes, complicated delivery was responsible for 57.4% of the deaths and 42.6% of the abortions. Indirect obstetrical causes were due to malaria (68.6%), heart disease (21.4%) and asthma (10%).. This high rate of maternal death illustrates the serious situation of obstetrics in our region. Our aim is to reduce this rate by promoting the Birth Place Without Risk program and improving management conditions. Implementation of this ambitious program requires implication of political decisions makers convinced of the importance of improving women's conditions and the health care system in Madagascar.

Topics: Asthma; Cause of Death; Female; Heart Diseases; Hospitals, University; Humans; Infections; Madagascar; Malaria; Maternal Mortality; Obstetric Labor Complications; Obstetrics and Gynecology Department, Hospital; Pregnancy; Pregnancy Complications; Retrospective Studies

Anopheles funestus and Anopheles gambiae s.l. have been considered until now the major vectors of malaria everywhere in Madagascar. Anopheles mascarensis, a mosquito native to Madagascar, has been identified in Sainte-Marie island as a secondary vector only. In 1997, an entomological study was carried out to identify the malaria vectors in the area of Fort-Dauphin, South-East of Madagascar. Every month, mosquitoes were collected from landing catches on human volunteers (from 7:00 am to 5:00 pm inside dwellings and from 7:00 am to 0:00 pm outside) and from knockdown spray-collections indoors. An mascarensis was the most abundant mosquito, the average number of An. mascarensis bites per man/night was 7.6. The sporozoite index was 0.89%. Despite the presence of An. funestus and An. gambiae s.l., An. mascarensis was found to be responsible for 2/3 of the infectious bites (25 infectious bites per man/year). An. mascarensis is widely distributed ih Madagascar but only specimens from the east coast have been found to carry sporozoites of human malaria. Further arguments are thus advanced for the hypothesis according to which a sibling species of An. mascarensis is present in Madagascar.

Topics: Animals; Anopheles; Humans; Insect Bites and Stings; Insect Vectors; Madagascar; Malaria; Population Density; Seasons

Polymorphism at nine microsatellite loci was examined to assess the level of genetic differentiation between four Anopheles arabiensis populations from Senegal, the high plateau of Madagascar, and Reunion and Mauritius islands. Eight of nine loci showed great polymorphism (2-16 alleles/locus) and significant genetic differentiation was revealed between all four populations by F- and R-statistics, with Fst estimates ranging from 0.080 to 0.215 and equivalent Rst values ranging between 0.022 and 0.300. These high amounts of genetic differentiation are discussed in relation to geographic distance including large bodies of water, and history of mosquito settlement, and insecticide use on the islands. The results suggest that historical events of drift rather than mutation are probably the forces generating genetic divergence between these populations, with homogenization of the gene pool by migration being drastically restricted across the ocean.

Topics: Animals; Anopheles; DNA; Electrophoresis, Polyacrylamide Gel; Female; Genetic Variation; Humans; Indian Ocean Islands; Insect Vectors; Linkage Disequilibrium; Madagascar; Malaria; Mauritius; Microsatellite Repeats; Polymerase Chain Reaction; Polymorphism, Genetic; Senegal

After the dramatic increase of malaria infections from 1985 to 1988 in the Highlands of Madagascar, the vector control programme was reactivated. In order to evaluate the impact of this strategy in the district of Arivonimamo, we have analysed the morbidity and the mortality data collected in all the health care centers of this district. Since 1988, extensive residual house spraying has been carried out on a yearly basis in the eastern part of this district whereas the western part was not included in this spraying programme. Data from each area were compared. In the eastern part, a dramatic decrease of morbitity and mortality related to malaria was observed, the benefit was 69% of expected simple cases, 87% of expected serious cases and 40% of expected deaths due to malaria. It has to be noted that only presumptive cases have been reported since no laboratory facilities are available in these health centers. Nevertheless such findings provide strong support to the continuation of the spraying programme, maybe in a less intensive way, together with an accurate epidemiological surveillance.

Topics: Humans; Madagascar; Malaria; Morbidity; Mosquito Control

Different malarial situations in Africa within the past 40 years are discussed in order to evaluate the impact of climatic and human factors on the disease. North of the equator, more droughts and lower rainfall have been recorded since 1972; and in eastern and southern Africa, there have been alternating dry and wet periods in relation to El Niño. Since 1955, the increase in human population from 125 to 450 million has resulted in both expansion of land cultivation and urbanization. In stable malaria areas of West and Central Africa and on the Madagascar coasts, the endemic situation has not changed since 1955. However, in unstable malaria areas such as the highlands and Sahel significant changes have occurred. In Madagascar, cessation of malaria control programs resulted in the deadly epidemic of 1987-88. The same situation was observed in Swaziland in 1984-85. In Uganda, malaria incidence has increased more than 30 times in the highlands (1,500-1,800 m), but its altitudinal limit has not overcome that of the beginning of the century. Cultivation of valley bottoms and extension of settlements are in large part responsible for this increase, along with abnormally heavy rainfall that favored the severe epidemic of 1994. A similar increase in malaria was observed in neighboring highlands of Rwanda and Burundi, and epidemics have been recorded in Ethiopia since 1958. In contrast, in the Sahel (Niayes region, Senegal), stricken by droughts since 1972, endemic malaria decreased drastically after the disappearance of the main vector, Anopheles funestus, due to the destruction of its larval sites by cultivation. Even during the very wet year of 1995. An funestus did not reinvade the region and malaria did not increase. The same situation was observed in the Sahelian zone of Niger. Therefore, the temperature increase of 0.5 degree C during the last 2 decades cannot be incriminated as a major cause for these malaria changes, which are mainly due to the combination of climatic, human, and operational factors.

Topics: Africa South of the Sahara; Climate; Eswatini; History, 20th Century; Humans; Madagascar; Malaria; Senegal; Uganda; Zimbabwe

Resistance of Plasmodium falciparum to chloroquine was first suspected in Madagascar in 1975 and later confirmed in vivo and in vitro. During the period from 1985 and 1990, the network of public health monitoring stations reported that 1% of the population living on the central Highlands of Madagascar died of malaria. Thereafter the National Malaria Control Program achieved good success by spraying homes with insecticide and reorganizing distribution of chloroquine in all villages. However data recorded between 1996 and 1998 indicates that, after four years of widespread chloroquine use, resistance to amino-4-quinolones is progressing in Madagascar. The tests described in this report were performed on patients with documented malaria included in cohorts and followed year round by a physician. The three villages studied were located along the borders of the highlands between the plateaus and coastal areas. In vivo tests showed that the incidence of chloroquine resistance was 0% in Mahakary, 32% in Ankazobe and 30% in Saharivo. Clinically, however, treatment was unsuccessful in only 16% and 8% of cases respectively. In vitro tests demonstrated chloroquine sensitivity in 79% of the 153 strains tested. No resistance to quinine or halofantrine was observed. In vitro tests indicated an onset of resistance to mefloquine. Although the success rate of chloroquine treatment is nearly 80%, spread of strongly chloroquine-resistant strains is a risk especially in subjects with mild immunity to malaria.

Topics: Animals; Antimalarials; Chloroquine; Communicable Disease Control; Drug Resistance, Microbial; Humans; Insect Vectors; Madagascar; Malaria; Microbial Sensitivity Tests; Plasmodium falciparum; Retrospective Studies

We report here a new variant of human malaria parasite found by comparison of diagnostic results obtained from a new DNA diagnostic method named microtiter plate-hybridization (MPH) and traditional microscopic method. Total five cases of malaria were diagnosed as microscopy-positive but MPH-negative; one case was found in epidemiological research in Vietnam and four cases were obtained from imported malaria in Japan. Although they were quite similar to typical P. ovale morphologically in microscopy, sequence analysis of PCR-amplified DNA fragment revealed that their 18S ribosomal RNA gene sequence was different from published sequence of P. ovale. Combination of MPH and microscopic examination provides us a new method for detection of a new type of malaria parasite which is difficult to distinguish morphologically.

Topics: Animals; DNA, Ribosomal; Genes, Protozoan; Genetic Variation; Humans; Madagascar; Malaria; Mali; Plasmodium; Polymerase Chain Reaction; RNA, Protozoan; RNA, Ribosomal, 18S; Tanzania

The authors reported the results of paludometric and entomological studies carried-out for two years: 1995-1996 in two localities: Ampanihy and Ankilimivory located in the South of Madagascar. These studies followed a suspect malaria epidemic in Ankilimivory in June and July 1994; the population plasmodic index was of 45%. In April 1995, this data was of 35% in Ampanihy and of 15% in Ankilimivory. Entomological studies carried out in April 1996 allowed to find Anopheles funestus in Ankilimivory and Anopheles gambiae l. s. in the two localities. Both the endemicity of malaria and the role of A. funestus had to be taken into account in the southern part of Madagascar. Until now, rare epidemics in this area were thought to occur only when climatic conditions were favorable, mainly during the rainy season. However, other factors, linked with the development could also facilitate the upset of epidemics, e.g.: irrigation programmes.

Topics: Adolescent; Adult; Age Distribution; Animals; Anopheles; Child; Child, Preschool; Endemic Diseases; Female; Humans; Incidence; Infant; Insect Vectors; Madagascar; Malaria; Male; Population Density; Population Surveillance; Prevalence; Seasons; Sex Distribution

Determine the sensitivity of the pathology examination of the placenta as a screening examination for malaria and the consequences of this infection on prematurity and birth-weight.. Eighty placentas were examined at the Mjunga, Madagascar dispensary at the beginning of the rainy season. The aspect of the placenta was compared with a malaria index and to malaria disease state as a function of parity and anti-malarial prophylaxis used by the mother as well as with the state of the infant.. Among the placentas examined, 41.3% were considered normal and abnormal or clearly pathological in 58.7%. Estimating the gestational age on the basis of the histological examination of the amniotic cells was in agreement with the gestational age calculated from the last cycle in 53 cases and in disagreement in 8 cases. The percentage of cases of malaria discovered by the pathology examination (20%) was greater than that after thick swab screening (10%). 75% of the mothers has Plasmodium falciparum infection at the time of delivery and 13.8% of the mothers with negative thick drops had malaria lesions of the placenta. The parity of infected mothers was similar to non infected mothers. All the premature newborns had pathological placentas included 12.5% with malarial lesions. 90% of the hypertrophic newborns had pathological placentas included 50% with malarial lesions. No case of congenital malaria was observed.. Pathology examination of the placenta is as sensitive as blood drop tests for screening for malaria. The histological examination of amniotic cells can give a good estimation of gestational age in developing countries.

Topics: Adolescent; Adult; Amnion; Birth Weight; Developing Countries; Female; Gestational Age; Humans; Hypertrophy; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Madagascar; Malaria; Malaria, Falciparum; Mass Screening; Parity; Placenta; Placenta Diseases; Pregnancy; Pregnancy Complications, Parasitic; Sensitivity and Specificity; Social Class

The Island of Sainte Marie is located at 6 km from the Eastern Coast of Madagascar. The climate is a muggy tropical one, with an average temperature rising above 20 degrees C all along the year and precipitations superior to 2500 mm. In 1990, a clinical surveillance of ten affections has been performed by every health units of the Island: paludal syndromes, nutrition disorders and anemia have been the focus of symptomatic definition. Blood samples have been taken from 100 pupils of the village of Ambodiforaha for hemogram determination and research of malaria hematozoon. Four pupils out of five show biological anemia, more than 10% suffer from acute anemia (less than 3.5 millions of red blood cells for each microliters, hematocrit inferior to 30, less than 9 g of hemoglobin for 100 ml). 87% suffer from nutritional anemia, 17% from iron-deficient anemia. Those figures cannot be found in health statistics. There is a high rate of nutritional and iron deficient anemia, but the problem is not well perceived or not at all by the health system. Anemia must be related to the strength of paludal transmission, to the importance of nutrition disorders and the prevalence of intestinal parasitosis. A better knowledge of the epidemiology of anemias and their morbid consequences would allow the setting of a prevention programme useful for children under 5 years and for pregnant women.

Topics: Adolescent; Anemia; Child; Child Nutrition Disorders; Child, Preschool; Female; Health Surveys; Hematocrit; Hemoglobins; Humans; Indian Ocean Islands; Intestinal Diseases, Parasitic; Madagascar; Malaria; Male; Population Surveillance; Prevalence; Referral and Consultation; Seasons

A study involving 169 schoolchildren (5-14 years old) living in Manarintsoa near Antananarivo (Madagascar, East Africa) was performed during the seasonal malaria transmission period. For the whole population examined, the prevalence of Plasmodium falciparum and the rates of spleen enlargement and of circulating stable antigen (S-Ag) were found to be 60.9%, 71.7%, and 46.8%, respectively. The prevalence of IgG antibody to RESA (ring-infected erythrocyte surface antigen) was 42.7% and that of IgG and IgM antibodies to E-Ag (exoantigens) was 44.9% and 2.9%, respectively. The positive rates for IgG and IgM antibodies to Som-Ag (somatic antigen) were 48.5% and 5.9%, respectively. Concerning S-Ag, no significant relationship was observed for parasitemia, spleen size, age, or IgM antibody responses to exoantigens (E-Ag) or to somatic antigen (Som-Ag). Levels of S-Ag were found to be related to IgG antibodies to E-Ag. Our results suggest that S-Ag at low levels may participate in the mechanisms involved in the development of the IgG antibody responses to E-Ag and to Som-Ag, whereas at a comparative population level, higher quantities of S-Ag down-regulate antibody responses to P. falciparum. The data we obtained were compared with those gathered in another malaria mesoendemic area (Bobo-Dioulasso, Burkina Faso, West Africa), where lower levels of S-Ag were found.

Topics: Adolescent; Age Factors; Animals; Antibody Formation; Antigens, Protozoan; Child; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin G; Immunoglobulin M; Madagascar; Malaria; Malaria, Falciparum; Malaria, Vivax; Plasmodium; Plasmodium falciparum; Plasmodium vivax; Prevalence; Spleen

A 17-mo longitudinal malaria survey (November 1988-March 1990) was carried out on Sainte Marie Island, an area on the east coast of Madagascar which is frequently visited by tourists. During 706 man-nights of capture, 46,401 mosquitoes belonging to 32 species were caught. Sporozoite rates were determined by ELISA and incriminated Anopheles gambiae Giles s.s., An. funestus Giles, and An. mascarensis De Meillon as vectors of malaria. An. gambiae, the main vector, was highly anthropophilic but largely exophilic. Transmission by this species occurred mainly from November to April; the overall circumsporozoite antigen positivity rate was 1.7%, with a maximum of 3.2% in March-April. The nightly peak of transmission occurred between midnight and 0400 hours. The annual inoculation rate was calculated to be 100 infective bites per human, of which 92 were of Plasmodium falciparum. An. funestus played a minor role in transmission. An. mascarensis, an anopheline endemic to Madagascar, was incriminated for the first time, as a malaria vector. The sporozoite rate in this species varied from 0.4 to 0.9% as shown by both ELISA and salivary gland dissections. Parasite indices in humans up to 20 yr of age fluctuated during the year from 64 to 80%. Bed nets are recommended for malaria protection for the local population and tourists.

Topics: Animals; Anopheles; Female; Humans; Insect Bites and Stings; Insect Vectors; Madagascar; Malaria; Plasmodium

A 17-month longitudinal malaria survey was carried out in Sainte Marie Island, on the East Coast of Madagascar, from November 1988 to March 1990. During 706 man-nights of captures, 46401 mosquitoes belonging to 32 species were caught. Sporozoïte rates were calculated by Elisa. The malaria vectors were Anopheles gambiae sensu stricto, An. funestus and An. mascarensis. An. gambiae was the main vector. It was highly anthropophilic and partially exophilic. Transmission by this species mainly occurred from November to April, monthly sporozoïte antigene positivity rate varied from 0 to 3.85. The annual inoculation rate was about 100 infecting bites per man, in which 92 by Plasmodium falciparum. An. funestus intervened weakly in transmission. An. mascarensis, a malagasy endemic region anopheline is a newly discovered vector. The observed sporozoïte rate varied from 0.4 to 0.9 between September and March 1990. Parasite indexes in human fluctuated during the year from 64 to 80%. Because of the high level of transmission, recommendations for inhabitants and tourists are proposed.

Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Culicidae; Entomology; Enzyme-Linked Immunosorbent Assay; Humans; Infant; Infant, Newborn; Insect Vectors; Longitudinal Studies; Madagascar; Malaria; Polymerase Chain Reaction; Population Surveillance; Seasons

The ring-infected erythrocyte surface antigen (RESA), a Plasmodium falciparum merozoite antigen, is a major vaccine candidate against falciparum malaria. To investigate the protective role of antibodies to RESA and its 4-mer, 8-mer, and 11-mer repeated amino acid sequences under conditions of natural exposure, a case-control and a cohort study were carried out in 1988 in a rural community in Madagascar where malaria reappeared recently. Fifty cases with greater than 1,000 P. falciparum per microliter of blood, and 45 controls with a negative blood smear were enrolled and sera were collected. Forty-one controls were followed for 20 weeks to identify malarial attacks. Protection against clinical malaria was assessed by the absence of malarial attacks requiring therapy. At enrollment, positivity rates and reactivity levels to RESA or repeats were similar in cases and controls. The 11-mer repeat antibody level was higher in the 26 controls who experienced at least one malarial attack during follow-up than in the 15 other controls (p less than 0.01). Thus, antibodies to the 11-mer repeat were predictors of the subsequent appearance of the disease. After adjustment for antibodies to the 11-mer repeat, antibodies to whole RESA had a negative predictive value on the occurrence of malarial attacks (p = 0.04). Different epitopes within the RESA molecule may elicit production of antibodies with different activities.

Topics: Adult; Animals; Antibodies, Protozoan; Antigens, Surface; Case-Control Studies; Cohort Studies; Humans; Madagascar; Malaria; Plasmodium falciparum; Protozoan Proteins

Topics: Adolescent; Adult; Animals; Chloroquine; Drug Administration Schedule; Drug Resistance; Female; Humans; Madagascar; Malaria; Male; Pefloxacin; Plasmodium falciparum

In a community follow-up conducted in the Central Highlands of Madagascar, the cellular responses to synthetic peptides from the immunodominant regions of Pf155/RESA and the repeat region of the circumsporozoite protein were studied. Seasonal variations of the T cell response were measured at the individual level; the relationship between this response and the presence of parasites in blood was assessed; the question of the possible protective value of the lymphocyte proliferation in presence of a specific antigen was addressed.

Topics: Adolescent; Adult; Aged; Amino Acid Sequence; Animals; Antigens, Protozoan; Antigens, Surface; Child; Epitopes; Humans; Immunity, Cellular; Longitudinal Studies; Madagascar; Malaria; Middle Aged; Molecular Sequence Data; Peptide Fragments; Plasmodium falciparum; Protozoan Proteins; Seasons

Topics: Animals; Female; France; Humans; Infant, Newborn; Madagascar; Malaria; Plasmodium vivax

Topics: Adolescent; Adult; Aged; Animals; Carrier State; Child; Child, Preschool; Disease Vectors; Female; Humans; Infant; Infant, Newborn; Madagascar; Malaria; Male; Middle Aged; Plasmodium falciparum; Plasmodium vivax; Seasons; Severity of Illness Index; Weather

This survey carried out from March to June 1989, demonstrated the important part of An. funestus in malaria transmission, in MAHISTY, a village near the malagasy capital city. End of March, the number of An. funestus bites reached 6 per man per night, and only 0.75 for An. gambiae s.l. In March a mean of 23 An. funestus per room were found as indoor resting mosquitoes. One indoor resting An. funestus, caught in June, was positive against P. vivax by ELISA. Observed of 52 indoor-resting An. funestus was 100%. In this village, Plasmodium indexes were 60%.

Topics: Adolescent; Animals; Anopheles; Child; Child, Preschool; Humans; Infant; Infant, Newborn; Insect Vectors; Madagascar; Malaria; Plasmodium falciparum; Plasmodium vivax; Prevalence; Rain; Seasons; Urban Population

To evaluate the factors determining malaria transmission level, entomological and parasitological surveys were conducted from October 1988 to February 1990 in MANARINTSOA, in the central highland plateaux of MADAGASCAR. Mosquitoes were collected during 928 man-nights of captures, in pit shelters and in indoors resting sites. The malaria vectors were An. arabiensis and An. funestus, with no evidence of the presence of An. gambiae s.s. The vectors were mainly exophilic and zoophilic. The index of stability was below 1.5. The sporozoite rate was 0.11 for An. gambiae s.l. and 0.47 for An. funestus. The transmission level was low: the inoculation rate was 0.91 infected bite per man and per year and the infection risk 0.62. Transmission occurs 7 months per year, from November to May. In the human population parasite rates fluctuated from 29% in October to 53% in May.

Topics: Altitude; Animals; Anopheles; Circadian Rhythm; Feeding Behavior; Humans; Insect Vectors; Madagascar; Malaria; Risk Factors; Seasons

Topics: Adolescent; Adult; Age Factors; Animals; Child; Child, Preschool; Humans; Infant; Infant, Newborn; Longitudinal Studies; Madagascar; Malaria; Plasmodium falciparum; Plasmodium malariae; Seasons; Severity of Illness Index; Weather

Topics: Adolescent; Animals; Antibodies, Protozoan; Child; Child, Preschool; Humans; Madagascar; Malaria; Plasmodium falciparum; Schools; Seasons; Severity of Illness Index

Topics: Animals; Antimalarials; Chloroquine; Drug Resistance; Female; Madagascar; Malaria; Male; Plasmodium falciparum

Plasmodium falciparum has recently reappeared in the central highland plateaux of Madagascar. To define its role in the overall malaria pathology occurring during the rainy season, we conducted a clinical and parasitological study among the 2776 consultants of a malaria field health centre which we established in the middle of the transmission area. From January to June 1988 the overall parasite rate was 63.2% and did not vary with age; the overall splenic rate was 46.9%, decreasing in individuals over 15 years of age. After the beginning of the main transmission season, an increase in parasite rates and parasite densities was observed, while febrile illnesses associated with malaria parasitaemia decreased. During the second part of the rainy season the parasite densities started to decrease, while parasite rates and malaria-associated fevers remained at the same level. The frequency of fevers was not related to the malaria parasite density owing to individual and seasonal variations.

Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Female; Humans; Infant; Madagascar; Malaria; Male; Plasmodium falciparum; Prevalence; Rural Population

To evaluate the factors which determine the transmission level of falciparum malaria, entomological and parasitological surveys were conducted from October 1988 to February 1990 in Manarintsoa in the central highland plateaux of Madagascar. Mosquitoes were collected for 928 man-nights in pit shelters and indoor resting sites. Malaria vectors were Anopheles arabiensis and An. funestus, with no evidence of the presence of An. gambiae sensu stricto. Vectors were mainly exophilic and zoophilic. The index of stability was less than 1.5. The sporozoite rate was 0.11 for An. gambiae sensu lato and 0.47 for An. funestus. The transmission level was low, with an inoculation rate of 0.91 infective bites/person/year and an infection risk of 0.62. Malaria transmission occurs 7 months of the year in this area, from November to May. Human parasite rates fluctuated from 29% in October to 53% in May.

Topics: Animals; Anopheles; Cold Temperature; Feeding Behavior; Humans; Insect Vectors; Madagascar; Malaria; Plasmodium falciparum; Plasmodium malariae; Plasmodium vivax; Seasons

The new epidemic of malaria which spread on the Madagascar high plateau in 1986-1987 is due to the combination of several factors (some of which are analysed by the authors, especially those related to anopheles, parasite and man). The authors compare the situations on the high Plateau and on St Mary Island, on the East Madagascar Coast, where the malaria is stable. Concerning the vector, the most interesting fact is the come-back of Anopheles funestus on the high Plateau from which it had disappeared at the beginning of the fifties. In this area, An.arabiensis seems to be the only representative of the gambiae complex whereas it is An. gambiae s.s. in St Mary Island. The parasite is getting more and more resistant to chloroquine. Nevertheless, man seems to develop protection, but it is difficult to analyse the markers which would prove the protection. However, that protection was assessed, on the humoral and cellular level, against the peptides of the RESA (Ring Infected Erythrocytes Surface Antigen), the circumsporozoite protein and the antigen E.

Topics: Adolescent; Animals; Anopheles; Antimalarials; Child; Disease Outbreaks; Drug Resistance; Ecology; Host-Parasite Interactions; Humans; Insect Vectors; Madagascar; Malaria; Plasmodium falciparum

Resurgence of falciparum malaria occurred in the Central Highlands of Madagascar in the 1980s and the disease is currently hyperendemic. We determined the humoral and cellular responses to synthetic peptides reproducing the repeat sequences of 2 major Plasmodium falciparum antigens: the Pf155/RESA and the circumsporozoite (CS) protein. Blood samples from 83 subjects living in a rural community near Antananarivo were obtained at the beginning and the end of the transmission season. At enrollment, 40 subjects presenting with and 43 without blood parasites had similar T cell proliferative response and antibody level to all antigens tested. However, P. falciparum-infected individuals exhibited a decrease in the absolute number of T lymphocytes, due to a diminished number of CD8+ and natural killer lymphocytes. The number of CD4+ cells was similar in both groups. In the overall population, 45% of subjects had a T cell response to at least 1 RESA peptide (29-35% responding to a given peptide) and 35% to the CS protein peptide. Thirty-two percent of the donors presented with RESA antibodies and 23% had CS protein antibodies. After 20 weeks, at the end of the transmission season, cellular proliferative responses to all antigens markedly decreased as evidenced by a decrease of both the number of responders and mean stimulation indexes. Humoral response to RESA, as detected by erythrocyte membrane immunofluorescence (number of responders and mean antibody titers) markedly increased. Humoral responses to the CS protein and RESA peptides were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Animals; Antibodies, Protozoan; Antigens, Protozoan; Antigens, Surface; Base Sequence; Child; Cohort Studies; Female; Humans; Lymphocyte Activation; Madagascar; Malaria; Male; Middle Aged; Molecular Sequence Data; Plasmodium falciparum; Protozoan Proteins; T-Lymphocytes

This survey carried out in 1989, confirms the part played by An. funestus in the transmission of malaria, in some villages of the Malagasy Highlands.

Topics: Animals; Anopheles; Humans; Insect Vectors; Madagascar; Malaria; Population Density; Seasons

A recent malaria epidemic striking Antananarivo, the capital city of Madagascar, is shown from hospital records of Pediatric Service "A" of the Befelatanana General Hospital. From 1980 to 1988 malaria cases in this hospital service increased from 0.9% to 14.4% of all admissions (on average 1785 per year). The unexpected expansion is observed in 1984, 1985 and 1986 and since that time malaria has apparently maintained a stable endemic level. Malaria mortality as a proportion of general mortality in the service followed a parallel course but the case fatality rate remained constant during the whole period, in spite of the progressive increase of cerebral malaria (coma) cases. Hospitalized malaria children came mainly from Western and Southern urban and periurban areas of Antananarivo, more rarely from the central areas, the hilly zone, the North and the East of the city.

Topics: Adolescent; Animals; Child; Child, Preschool; Cluster Analysis; Cohort Studies; Disease Outbreaks; Humans; Infant; Infant, Newborn; Madagascar; Malaria; Plasmodium falciparum; Plasmodium vivax; Urban Population

An entomological survey carried out between october 1987 and july 1988 in Manarintsoa, a village 30 Km West of Antananarivo, shows that An. gambiae s.l. and An. funestus are both vectors of malaria. The sporozoite rate was estimated at 0.71%, and the annual risk about 2 infectious bites per person. In all, more than 16,000 mosquitoes, belonging to at least 15 species, were caught over a period of 294 nights.

Topics: Animals; Anopheles; Culicidae; Insect Vectors; Madagascar; Malaria; Population Density

Topics: Child; Child, Preschool; Humans; Infant; Madagascar; Malaria; Nervous System Diseases

The Malaria Research Unit of the Madagascar Pasteur Institute and the local health authorities carried out a study in the Sainte Marie Island in August 1988. Epidemiological results were in agreement with those previously reported in areas of endemic malaria. Parasite and splenomegaly rates were 34.6 and 35.9% respectively, by both active and passive cases detection. Analysis of parasite densities and clinical symptoms in the various age groups demonstrates that protective immunity is absent in infants and young children, and appears by the age of 2 to 9 years. An in vivo study of the sensitivity of Plasmodium falciparum to chloroquine was conducted in 41 patients. 39% of the infections were normally sensible (S) to WHO standard therapy (25 mg chloroquine/kg in 3 days), while 32% of the patients presented with a thick blood smear negative by D7, but positive by D14 (S/R1). Parasite resistance was observed in 29% of the infections: in 10% at the R1 level, and in 19% at the R2 level. Frequency and level of resistance to chloroquine are higher than those we observed in the East Coast in 1983 and 1985. However, chloroquine consistently achieves a high reduction in parasite densities and is still clinically active.

Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Chloroquine; Female; Humans; Infant; Madagascar; Malaria; Male; Plasmodium falciparum; Population Surveillance; Rural Population

We studied 521 serum samples collected in 1987-88 in the Highland Plateaux and the East coast of Madagascar, two areas presenting different levels of malaria endemicity. Total anti-Plasmodium falciparum antibodies were investigated by an indirect immunofluorescence assay (IFA). Antibodies directed to the ring-infected erythrocyte surface antigen (RESA) were investigated by a modified IFA (MIFA). Results were analysed in regards to malariological parameters (parasite and splenomegaly rates) collected simultaneously. IFA appears as a good epidemiological tool as it closely parallels the classical malariological parameters. In selected studies, the presence of P. falciparum parasites in blood was less frequent in individuals presenting with anti-RESA antibody, as detected by MIFA, than in the other individuals were consistently lower in subjects with anti-RESA antibody than in others.

Topics: Animals; Antibodies, Protozoan; Antigens, Protozoan; Antigens, Surface; Child; Fluorescent Antibody Technique; Humans; Madagascar; Malaria; Plasmodium falciparum; Protozoan Proteins

In 1988, the sensitivity to chloroquine was investigated by the standard WHO in vivo test in 91 Plasmodium falciparum-infected individuals from the Highland Plateaux of Madagascar. As compared to the previous years, the level of resistance to chloroquine was increased, R2 resistant strains being present. This study also allows to define a policy for chloroquine therapy of patients. Following the malaria diagnosis by microscopy at DO, a single blood smear on D4 may indicate the parasitological cure for sensitive strains. However, 2 additional blood smears, on D7 and D14, are needed due to the presence of SR1, R1, and R2 strains. In all cases, a thick blood smear is required for microscopic observation, as the thin smear possess an insufficient threshold of sensitivity.

Topics: Animals; Chloroquine; Humans; Madagascar; Malaria; Microbial Sensitivity Tests; Plasmodium falciparum; Rural Population

In 1988, the Malaria Research Unit of the Madagascar Pasteur Institute settled an out-patients clinic in Manarintsoa, a village of the Highland Plateaux where epidemic malaria appeared recently. 2776 consultants presented between January and June. In addition, the 200 schoolchildren were examined thrice. For each individual, clinical examination and thick and thin blood smears were performed. In the out-patients, parasite rates were above 50% each month and in each age group; the mean parasite rate being 74%. Splenomegaly rates were above 60% in individuals less than 15 years of age, and around 20% in adults. In schoolchildren, parasite and splenomegaly rates are consistently above 50%. Gametocyte indexes were 7.5% and 7% in May and October, respectively. Plasmodium falciparum is the most encountered species (in 85% of the cases), but P. vivax and P. ovale are also present. P. malariae is very rare. Early diagnosis and adequate therapy were very effective against mortality. During the high transmission time, monthly mortality rates varied from 12% before our arrival to 0.66% after. The number of malaria attacks was estimated at 2 per man and per year. In this area of unstable malaria, presence of fever appears to be of poor predictive value of the malaria infection. Systematic chloroquine therapy of fevers would be adapted to only 43% of the cases.

Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Female; Humans; Infant; Madagascar; Malaria; Male; Mass Screening; Plasmodium falciparum; Rural Population; Splenomegaly

Topics: Animals; Child; Child, Preschool; Humans; Madagascar; Malaria; Plasmodium falciparum; Seasons

Topics: Aedes; Animals; Anopheles; Culex; Culicidae; Humans; Insect Vectors; Longitudinal Studies; Madagascar; Malaria

With the Le Bras's isotopic semi-microtest method, the authors have studied 139 strains of Plasmodium falciparum isolated in a village near Tananarive in the Highlands of Madagascar. Conditional malariometric rates show the increase of the recrudescence of Malaria in the area which was recently considered as "surveillance area". 5.8% of the 139 studied strains show an in vitro resistance higher than 120 nmoles/l, but whose the level is ever lower than in Africa. 4.3% exhibit a level between 90 and 120 nmoles/l. These values give better prospect for the Isle because the resistance strain rates have remain nearly stable since 1982. The resistance level is always low.

Topics: Animals; Child; Child, Preschool; Chloroquine; Drug Resistance; Humans; Madagascar; Malaria; Plasmodium falciparum

Topics: Adolescent; Adult; Animals; Child; Child, Preschool; Chloroquine; Drug Resistance; Humans; Infant; Madagascar; Malaria; Plasmodium falciparum

Topics: Animals; Antibodies, Protozoan; Child; Fluorescent Antibody Technique; Humans; Madagascar; Malaria; Plasmodium falciparum

Topics: Animals; Antimalarials; Drug Evaluation, Preclinical; Madagascar; Malaria; Mice; Plant Extracts; Plants, Medicinal; Plasmodium berghei

Topics: Animals; Humans; Madagascar; Malaria; Plasmodium

Topics: Animals; Anopheles; Humans; Insect Vectors; Madagascar; Malaria

Antibodies directed against antigens of the asexual blood stages of Plasmodium falciparum were studied in the plasma of 29 individuals infected with P. falciparum and living in two areas of Madagascar. These plasma samples were investigated by four immunological methods: indirect fluorescence, immunoprecipitation of radiolabeled P. falciparum polypeptides, inhibition of the in vitro growth of P. falciparum, and double diffusion in a gelose plate. A multifactorial correspondence analysis of the results obtained for each sample revealed that the nature of several of the antibodies varied according to the age and place of residence of the subjects. In comparison with plasma samples from older individuals, specimens from young children had a higher immunofluorescence titer, immunoprecipitated several additional peptides (90, 110, and 118 kilodaltons), revealed more precipitation lines in the Ouchterlony plate technique, and did not inhibit the in vitro growth of P. falciparum to the same extent. Furthermore, as opposed to plasma samples from individuals living in the high central plateau, plasma samples from individuals living on the east coast of the island inhibited the penetration of erythrocytes by merozoites of one of the two studied P. falciparum strains and preferentially immunoprecipitated low-, rather than high-, molecular-weight peptides.

Topics: Adolescent; Adult; Animals; Antibodies; Antigens, Protozoan; Child; Child, Preschool; Electrophoresis, Polyacrylamide Gel; Erythrocytes; Fluorescent Antibody Technique; Humans; Immunodiffusion; Immunologic Techniques; Madagascar; Malaria; Plasmodium falciparum

One thousand and twenty six P. falciparum strains isolated from cases imported in France and field surveys in four regions of Africa and Madagascar were studied in vitro against chloroquine, monodesethylamodiaquine, quinine and mefloquine, 917 in vivo tests were performed during field studies with chloroquine (10 and 25 mg/kg) and amodiaquine (10, 25, 35 mg/kg). In Madagascar, the chemoresistance remained low and stable during the study period, concerning mostly chloroquine (11% in vitro and in vivo) without obvious geographical variation. 25 mg/kg chloroquine or amodiaquine were satisfactory as respectively first and second line therapeutic regimen. In Central Africa, chemoresistance emerged with an epidemic profile and increased dramatically in disseminated urban focus. High level and prevalence of chloroquine resistance and multiresistance were observed few months after the index cases in these foci. In South West Cameroon, amodiaquine remained efficient as curative treatment but only at a dose of 35 mg/kg/5 days. Decrease of in vitro sensitivity and in vivo efficacy of quinine is a matter of concern. Given the heterogeneous and evolutive situation of drug resistance, the need for epidemiological surveillance and monitoring of P. falciparum drug sensitivity in Africa is obvious to adjust therapeutic regimen.

Topics: Amodiaquine; Angola; Animals; Antimalarials; Burkina Faso; Cameroon; Chloroquine; Drug Resistance; Humans; Madagascar; Malaria; Mefloquine; Plasmodium falciparum; Quinine; Quinolines

Topics: Adolescent; Adult; Aminoquinolines; Amodiaquine; Animals; Child; Child, Preschool; Chloroquine; Drug Resistance; Humans; Infant; Madagascar; Malaria; Plasmodium falciparum

Topics: Adolescent; Amodiaquine; Animals; Child; Child, Preschool; Chloroquine; Drug Resistance; Humans; Infant; Madagascar; Malaria; Plasmodium falciparum

Topics: Adolescent; Blood; Child; Child, Preschool; Humans; Madagascar; Malaria; Plasmodium falciparum; Plasmodium malariae; Plasmodium vivax

Topics: Adolescent; Amodiaquine; Child; Child, Preschool; Chloroquine; Drug Resistance; Humans; Madagascar; Malaria; Plasmodium falciparum

Plasma samples from 50 subjects living in three distinct regions in Madagascar (Ankazobe, Manakara, and Foulpointe) were studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis of immunoprecipitated proteins from a Plasmodium falciparum strain (FCM22/Madagascar) which had been biosynthetically labelled with 35S-methionine and maintained in long-term in-vitro culture. Four major proteins with molecular weights of 96, 100, 110, and 118 kD were precipitated by plasma from Ankazobe, whereas low molecular weight proteins (27, 40, and 47 kD) were recognised more often by plasma from Foulpointe. Plasma from Manakara immunoprecipitated proteins of intermediate molecular weight. Variations in the immunological response according to the area, or antigenic diversity among the parasitic isolates might account for these results.

Topics: Adolescent; Adult; Antibodies; Antigens; Female; Humans; Madagascar; Malaria; Male; Plasmodium falciparum; Precipitin Tests

The sensitivity level of Plasmodium falciparum isolates to chloroquine and the activity of six other antimalarials were studied in the different climatic zones of Madagascar in 1983. In vivo tests were done with 10 and 25 mg kg-1 of chloroquine and amodiaquine. Early recrudescence or RII resistance was observed after treatment with 10 mg kg-1 of these drugs in 34% of the cases for chloroquine and 6.5% for amodiaquine, and after the 25 mg kg-1 dose in 7% and 0% of the cases respectively. In vitro sensitivity of 84 P. falciparum isolates to seven drugs were studied with a semi-microtest. For chloroquine, 9% of the isolates had an IC50 above 250 nM, indicating resistance. In vitro activity of piperaquine was high for all isolates except two. In vitro activity of amodiaquine, dichlorquinazine, quinine, mefloquine and halofantrine was good against all isolates (maximum IC50 was 76, 92, 560, less than or equal to 20 and less than or equal to 12 nM, respectively). Correlation between the WHO standard field test and the in vitro semi-microtest was good. Resistance of P. falciparum to chloroquine was observed in the six survey areas, but the other tested drugs showed good activity. Since no cross-resistance to 4-aminoquinolines seems to exist in Madagascar, amodiaquine (the only one available at present) should be studied as an alternative to chloroquine in the prevention and treatment of falciparum malaria in this area.

Topics: Adolescent; Adult; Aged; Amodiaquine; Antimalarials; Child; Child, Preschool; Chloroquine; Humans; Infant; Madagascar; Malaria; Mefloquine; Microbial Sensitivity Tests; Middle Aged; Phenanthrenes; Piperazines; Plasmodium falciparum; Quinine; Quinolines

563 cases of Falciparum malaria were detected in 1984 and 1985 in 7 malarial zones covering 3 climatic regions in Madagascar. All subjects underwent a therapeutic test; 175 strains of Plasmodium falciparum were isolated for in vitro drug sensitivity studies. 28 strains which were moderately chloroquine resistant in vitro were identified in 1983 in these various zones. However, 16% strains studied in 1984 in Alatsinainy (plateaux area), were chloroquine-resistant in vitro. The in vitro sensitivity to the other amino-4-quinolines seemed to be retained. In vivo, 7% of resistance type RI or RII were noted with 25 mg/kg of chloroquine but none with 25 mg/kg of amodiaquine. The usual therapeutic schedule for partially immune subjects (10 mg/kg in one dose) was ineffective on day 7 in 34% of the cases with chloroquine and 5% of the cases with amodiaquine. In conclusion to this study, we recommend that chemoprophylaxis should be stopped in schools in Madagascar and that presumed malarial attacks should be treated with a minimum dose of 25 mg/kg of chloroquine in 3 days. We suggest that amodiaquine should be used in cases of therapeutic failure with chloroquine.

Topics: Aminoquinolines; Amodiaquine; Animals; Antimalarials; Chloroquine; Drug Resistance, Microbial; Humans; In Vitro Techniques; Madagascar; Malaria; Phenanthrenes; Piperazines; Plasmodium falciparum; Quinine; Quinolines

Topics: Amodiaquine; Chloroquine; Humans; Madagascar; Malaria; Plasmodium falciparum

Topics: Chloroquine; Drug Resistance, Microbial; Female; Humans; Madagascar; Malaria; Middle Aged; Plasmodium falciparum

Some past and present experiences in the use of antimalarial drugs, particularly for chemoprophylaxis, are reviewed. The failure in the long term of mass chemoprophylaxis with weekly chloroquine in children in Madagascar, Cameroon, and Senegal is discussed, the reasons for failure being an increasing lack of resources to ensure regular drug distribution and lack of supervision of dosage.The increasing number of reports confirming chloroquine resistance from East Africa over the last decade poses a serious threat to the future usefulness of chloroquine as an antimalarial agent in Africa. There is now an urgent need for extensive drug sensitivity tests, which should also include alternative antimalarial drugs. To rely on mass chemoprophylaxis as the main method of controlling malaria would appear to be no longer tenable.

Topics: Adolescent; Cameroon; Child; Child Health Services; Child, Preschool; Chloroquine; Female; Humans; Infant; Infant, Newborn; Madagascar; Malaria; Plasmodium falciparum; Pregnancy; Senegal

Two three weeks field studies were performed in Morondava (West Coast) and Nosy Be (North West Coast) respectively in January and April 1983. Among 110 malarial patients recruited through passive detection, 70 in vivo tests and 37 in vitro tests were performed. In vivo, within 7 days 10 mg/kg chloroquine failed in 8 of the 21 treated patients, 25 mg/kg chloroquine failed in 1/43 and none of these patients treated with 10 mg/kg amodiaquine failed. In vitro, 5 among 37 isolates had chloroquine IC50 more than 250 nM/1 which is predictive for resistance with the semi-microtest. All isolates were sensitive in vitro to low doses of amodiaquine, piperaquine and dichlorquinazine.

Topics: Adolescent; Aged; Aminoquinolines; Amodiaquine; Animals; Antimalarials; Child; Chloroquine; Drug Resistance, Microbial; Humans; Madagascar; Malaria; Piperazines; Plasmodium falciparum; Quinolines

In Manakara and Foulpointe (East Coast of Madagascar) 184 malarial patients were selected among 742 patients attending dispensaries. The 7 days in vivo tests was performed in 144 patients. 13/36 failure to alternative (10 mg/kg) and 1/61 failure to standard (25 mg/kg) chloroquine WHO tests were observed. 10 mg/kg oral amodiaquine failed within 7 days in 5/47 patients. The in vitro semi-microtest was performed with 27 isolates. 2/24 Plasmodium falciparum isolates were chloroquino-resistant (IC50 = 270 and 280 nM/1), 27/27 were sensitive to low doses of amodiaquine (max IC50 = 76 nM/1), 25/25 were very sensitive to dichlorquinazine (max IC50 = 83 nM/1) and with pipéraquine 22/24 were very sensitive (IC50 less than 75 nM/1) and 2 less sensitive (IC50 = 240 and greater than 140 nM/1).

Topics: Aminoquinolines; Amodiaquine; Antimalarials; Child; Chloroquine; Drug Resistance, Microbial; Humans; Madagascar; Malaria; Piperazines; Plasmodium falciparum; Quinolines

Topics: Aminoquinolines; Antimalarials; Drug Resistance, Microbial; Epidemiologic Methods; Humans; Madagascar; Malaria; Plasmodium falciparum

Among 273 malarial patients recruited through passive detection, 177 in vivo tests were performed in Andekaleka and Ankazobe and 23 in vitro tests in Ifanadiana, and Ankazobe (inland of Madagascar). In vivo, chloroquine failed within 7 days at 10 mg/kg in 28/86 patients, at 25 mg/kg in 7/34 and amodiaquine failed in 5/55 with 10 mg/kg and in 0/14 with 25 mg/kg. In vitro, the semi-microtest revealed resistance to chloroquine of 1/23 isolates (IC50 = 750 nM/1) but high sensitivity to amodiaquine, dichlorquinazine and piperaquine of all studied isolates (max IC50 = 92 nM/1).

Topics: Aminoquinolines; Amodiaquine; Antimalarials; Chloroquine; Drug Resistance, Microbial; Humans; Madagascar; Malaria; Piperazines; Plasmodium falciparum; Quinolines

Topics: Adolescent; Adult; Chloroquine; Drug Resistance, Microbial; Female; Humans; Madagascar; Malaria; Male; Plasmodium falciparum; Tanzania

Topics: Adolescent; Adult; Child; Child, Preschool; Chloroquine; Drug Resistance, Microbial; Female; Humans; In Vitro Techniques; Infant; Madagascar; Malaria; Male; Middle Aged; Plasmodium falciparum

Topics: Adolescent; Child; Female; Humans; Madagascar; Malaria; Male; Plasmodium falciparum; Plasmodium malariae; Plasmodium vivax

Topics: Agriculture; Disease Reservoirs; Filariasis; Humans; Madagascar; Malaria; Parasitic Diseases; Schistosomiasis; Urinary Tract Infections; Water Supply

3 African cases of chloroquine-resistent (RI) P. falciparum malaria, proved by recrudescences after administration of recommended doses and adequate serum levels of chloroquine, are described. The 3 patients, Swedish women aged 43, 27, and 41, had never visited areas where chloroquine-resistent P. falciparum is known to exist. 2 patients had taken regular prophylaxis with chloroquine, while the 3rd had interrupted chloroquine use with temporary use of pyrimethamine. All 3 were treated with chloroquine and had serum levels well above those considered necessary for cure of malaria due to sensitive strains of P. falciparum. All had recrudescences, ranging from 13 to 41 days after the previous chloroquine treatment. Reinfection was not possible for any of the patients and none took other drugs during the study period. In 2 cases the Rieckmann in vitro test for resistence failed. In 1 case from Madagascar the in vitro method described by Nguyen-Dinh and Trager produced results indicating resistence and in another case from Madagascar the results indicated probable resistence, but the procedure failed in the case from Kenya. The 2 cases mark the 1st time resistence has been reported from Madagascar. In vivo tests in all cases and in vitro results in 2 cases, together with the adequate serum levels of chloroquine, confirm that malaria due to chloroquine-resistent P. falciparum is being transmitted in some parts of Africa.

Topics: Adult; Chloroquine; Drug Resistance, Microbial; Female; Humans; Kenya; Madagascar; Malaria; Plasmodium falciparum

An evaluation of health problems is done in a village in Eastern Madagascar, where takes place a development programme. 217 inhabitants go through physical examination and lab tests are performed (Blood smear - Thick drop. Emmel test. Stools examination for parasites and enteroviruses). The epidemiologic investigation reveals the prevalences of Malaria (39,4 p. 100) intestinal schistosomiasis (59,9 p. 100) Ascaridiasis (61,3 p. 100) Hookworm (29,9 p. 100) Trichuriasis (19,8 p. 100) and sickle cells anemia (4,80 p. 100). The signs and symptoms are analysed, particularly spleen enlargement which is shown to be due to schistosomiasis. The local transmition pattern of schistosomiasis is investigated and, according to the malacological findings, is thought to be intermittent. The determination of the local hookworm is started. It should be Necator americanus. The sanitary programme to be set is considered regarding the local contexte.

Topics: Age Factors; Anemia, Sickle Cell; Animals; Ascaridiasis; Disease Vectors; Feces; Health Surveys; Hookworm Infections; Humans; Madagascar; Malaria; Mollusca; Sanitation; Schistosomiasis; Splenomegaly; Trichuriasis

The course of an investigation trip through Madagascar is sketched. It allowed to analyze the parasitological situation. It is explained with the sociological and economical facts and the unusual fauna of this island. The two biggest problems are Malaria tropica and schistosomatosis (bilharziasis). Further, Ancylostoma, Ascaris, taeniids, and Wuchereria occur. Plague is rare. Fasciola gigantica has been introduced since short time only. Introduction of other parasites must be feared. Sleeping illness and nagana are lacking, as well as rabies, yellow fever, Fasciola hepatica, Echinococcus granulosus, Hymenolepis nana, Trichinella spiralis and Dracunculus medinensis. Effective control measures may not be reasonable at present because of the socio-economic structure as a result of the former colonial status.

Topics: Alcoholism; Environment; Expeditions; Helminthiasis; Humans; Madagascar; Malaria; Parasitic Diseases; Public Health; Schistosomiasis; Socioeconomic Factors; Tropical Climate

Topics: History, 20th Century; Humans; Immunotherapy; Madagascar; Malaria; Plasmodium vivax

Topics: Disease Susceptibility; Humans; Madagascar; Malaria; Plasmodium vivax

Topics: Animals; Body Weight; Culicidae; Humans; Madagascar; Malaria; Malaria, Vivax

Topics: Aggression; Humans; Madagascar; Malaria

Topics: Black People; Disease; Expeditions; Humans; Madagascar; Malaria; Military Personnel

Topics: Humans; Madagascar; Malaria