clove and Influenza--Human

During the very early stage of the 2009 pandemic, mass chemoprophylaxis was implemented as part of containment measure. The purposes of the present study were to systematically review the retrospective studies that investigated the effectiveness of antiviral prophylaxis during the 2009 pandemic, and to explicitly estimate the effectiveness by employing a mathematical model.. A systematic review identified 17 articles that clearly defined the cases and identified exposed individuals based on contact tracing. Analysing a specific school-driven outbreak, we estimated the effectiveness of antiviral prophylaxis using a renewal equation model. Other parameters, including the reproduction number and the effectiveness of antiviral treatment and school closure, were jointly estimated.. Based on the systematic review, median secondary infection risks (SIRs) among exposed individuals with and without prophylaxis were estimated at 2.1% (quartile: 0, 12.2) and 16.6% (quartile: 8.4, 32.4), respectively. A very high heterogeneity in the SIR was identified with an estimated I2 statistic at 71.8%. From the outbreak data in Madagascar, the effectiveness of mass chemoprophylaxis in reducing secondary transmissions was estimated to range from 92.8% to 95.4% according to different model assumptions and likelihood functions, not varying substantially as compared to other parameters.. Only based on the meta-analysis of retrospective studies with different study designs and exposure settings, it was not feasible to estimate the effectiveness of antiviral prophylaxis in reducing transmission. However, modelling analysis of a single outbreak successfully yielded an estimate of the effectiveness that appeared to be robust to model assumptions. Future studies should fill the data gap that has existed in observational studies and allow mathematical models to be used for the analysis of meta-data.

Topics: Antiviral Agents; Coinfection; Contact Tracing; Disease Outbreaks; Humans; Influenza A Virus, H1N1 Subtype; Influenza, Human; Madagascar; Models, Biological; Post-Exposure Prophylaxis; Risk Factors; Treatment Outcome

Three epidemic waves of coronavirus disease-19 (COVID-19) occurred in Madagascar from March 2020 to May 2022, with a positivity rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of 21% to 33%. Our study aimed to identify the impact of COVID-19 on the epidemiology of seasonal respiratory viruses (RVs) in Madagascar. We used two different specimen sources (SpS). First, 2987 nasopharyngeal (NP) specimens were randomly selected from symptomatic patients between March 2020 and May 2022 who tested negative for SARS-CoV-2 and were tested for 14 RVs by multiplex real-time PCR. Second, 6297 NP specimens were collected between March 2020 and May 2022 from patients visiting our sentinel sites of the influenza sentinel network. The samples were tested for influenza, respiratory syncytial virus (RSV), and SARS-CoV-2. From SpS-1, 19% (569/2987) of samples tested positive for at least one RV. Rhinovirus (6.3%, 187/2987) was the most frequently detected virus during the first two waves, whereas influenza predominated during the third. From SpS-2, influenza, SARS-CoV-2, and RSV accounted for 5.4%, 24.5%, and 39.4% of the detected viruses, respectively. During the study period, we observed three different RV circulation profiles. Certain viruses circulated sporadically, with increased activity in between waves of SARS-CoV-2. Other viruses continued to circulate regardless of the COVID-19 situation. Certain viruses were severely disrupted by the spread of SARS-CoV-2. Our findings underline the importance and necessity of maintaining an integrated disease surveillance system for the surveillance and monitoring of RVs of public health interest.

Topics: COVID-19; Humans; Influenza, Human; Madagascar; Pandemics; Respiratory Syncytial Virus, Human; Respiratory Tract Infections; SARS-CoV-2; Seasons; Viruses

Influenza and respiratory syncytial virus (RSV) infections are responsible for substantial global morbidity and mortality in young children and elderly individuals. Estimates of the burden of influenza- and RSV-associated hospitalization are limited in Africa.. We conducted hospital-based surveillance for laboratory-confirmed influenza- and RSV-associated severe acute respiratory illness (SARI) among patients of any age at one hospital and a retrospective review of SARI hospitalizations in five hospitals situated in Antananarivo during 2011-2016. We estimated age-specific rates (per 100 000 population) of influenza- and RSV-associated SARI hospitalizations for the Antananarivo region and then extrapolated these rates to the national level.. Overall, the mean annual national number of influenza-associated SARI hospitalizations for all age groups was 6609 (95% CI: 5381-7835-rate: 30.0; 95% CI: 24.4-35.6), 4468 (95% CI: 3796-5102-rate: 127.6; 95% CI: 108.4-145.7), 2141 (95% CI: 1585-2734-rate: 11.6; 95% CI: 8.6-14.8), and 339 (95% CI: 224-459-rate: 50.0; 95% CI: 36.3-74.4) among individuals aged <5, ≥5, and ≥65 years, respectively. For these same age groups, the mean annual number of RSV-associated SARI hospitalizations was 11 768 (95% CI: 10 553-12 997-rate: 53.4; 95% CI: 47.9-59.0), 11 299 (95% CI: 10 350-12 214-rate: 322.7; 95% CI: 295.6-348.8), 469 (95% CI: 203-783-rate: 2.5;95% CI: 1.1-4.2), and 36 (95% CI: 0-84-rate: 5.8; 0.0-13.5), respectively.. The burden of influenza- and RSV-associated SARI hospitalization was high among children aged <5 years. These first estimates for Madagascar will enable government to make informed evidence-based decisions when allocating scarce resources and planning intervention strategies to limit the impact and spread of these viruses.

Topics: Acute Disease; Adolescent; Adult; Aged; Child; Child, Preschool; Cost of Illness; Female; Hospitalization; Humans; Infant; Influenza, Human; Madagascar; Male; Middle Aged; Respiratory Syncytial Virus Infections; Retrospective Studies; Risk Factors; Young Adult

Evaluation of influenza surveillance systems is poor, especially in Africa.. In 2007, the Institut Pasteur de Madagascar and the Malagasy Ministry of Public Health implemented a countrywide system for the prospective syndromic and virological surveillance of influenza-like illnesses. In assessing this system's performance, we identified gaps and ways to promote the best use of resources. We investigated acceptability, data quality, flexibility, representativeness, simplicity, stability, timeliness and usefulness and developed qualitative and/or quantitative indicators for each of these attributes.. Until 2007, the influenza surveillance system in Madagascar was only operational in Antananarivo and the observations made could not be extrapolated to the entire country.. By 2014, the system covered 34 sentinel sites across the country. At 12 sites, nasopharyngeal and/or oropharyngeal samples were collected and tested for influenza virus. Between 2009 and 2014, 177 718 fever cases were detected, 25 809 (14.5%) of these fever cases were classified as cases of influenza-like illness. Of the 9192 samples from patients with influenza-like illness that were tested for influenza viruses, 3573 (38.9%) tested positive. Data quality for all evaluated indicators was categorized as above 90% and the system also appeared to be strong in terms of its acceptability, simplicity and stability. However, sample collection needed improvement.. The influenza surveillance system in Madagascar performed well and provided reliable and timely data for public health interventions. Given its flexibility and overall moderate cost, this system may become a useful platform for syndromic and laboratory-based surveillance in other low-resource settings.. La evaluación de los sistemas de vigilancia de la gripe es escasa, sobre todo en África.. En 2007, el Instituto Pasteur de Madagascar y el Ministerio de Salud Pública de Madagascar implementaron un sistema nacional para la futura vigilancia sindrómica y epidemiológica de enfermedades similares a la gripe. Al evaluar el rendimiento de este sistema, se identificaron lagunas y formas de fomentar el mejor uso de los recursos. Se investigaron la aceptación, la calidad de la información, la flexibilidad, la representación, la simplicidad, la estabilidad, el momento y la utilidad, y se desarrollaron indicadores cualitativos y/o cuantitativos para cada uno de estos atributos.. Hasta 2007, el sistema de vigilancia de la gripe en Madagascar operaba únicamente en Antananarivo, y las observaciones realizadas no podían extrapolarse al resto del país.. En 2014, el sistema abarcaba 34 sitios centinela en todo el país. En 12 sitios, se recogieron muestras nasofaríngeas y/o bucofaríngeas, que se sometieron a pruebas del virus de la gripe. Entre 2009 y 2014 se detectaron 177 718 casos de fiebre, 25 809 (14,5%) de los cuales se clasificaron como casos de enfermedades similares a la gripe. De las 9 192 muestras de pacientes con enfermedades similares a la gripe sometidos a pruebas del virus de la gripe, 3 573 (38,9%) resultaron positivas. La calidad de los datos para todos los indicadores evaluados se categorizó como superior al 90% y el sistema también parecía ser sólido en cuanto a su aceptación, simplicidad y estabilidad. No obstante, la recogida de muestras necesitaba mejorar.. El sistema de vigilancia de la gripe en Madagascar obtuvo buenos resultados y ofreció información fiable y oportuna para las intervenciones de salud pública. Dada su flexibilidad y el coste moderado general, este sistema podría convertirse en una plataforma útil para la vigilancia sindrómica y en laboratorios en otros entornos con pocos recursos.. ضعف تقييم نظم ترصد الإنفلونزا خاصةً في أفريقيا.. حتى عام 2007، تم تشغيل نظام رصد الأنفلونزا في مدغشقر في أنتاناناريفو فقط، وتعذر استقراء الملاحظات للبلد بأكمله.. بحلول عام 2014، غطى النظام 34 موقعًا رصديًا في جميع أنحاء البلاد. وتم جمع عينات بلعومية و/أو فموية بلعومية واختبارها لاكتشاف فيروس الإنفلونزا في 12 موقعًا. تم اكتشاف 177,718 حالة حمى في الفترة ما بين عامي 2009 و2014، وتم تصنيف 25,809 (‏14.5‏%) حالة من هذه الحالات على أنها أمراض مماثلة للإنفلونزا. وكان من بين 9192 عينة من المرضى المصابين بأمراض مماثلة للإنفلونزا والتي تم اختبارها لاكتشاف فيروس الإنفلونزا، ثبتت إصابة 3573 (‏38.9‏%) حالة. أشار تصنيف جودة البيانات لجميع المؤشرات التي تم تقييمها إلى نسبة تتعدى 90‏‏%، كما ظهر النظام قويًا فيما يتعلق بالمقبولية والبساطة والاستقرار. ومع ذلك، يلزم إدخال التحسين على عملية جمع العينات.. حقق نظام رصد الإنفلونزا في مدغشقر أداءً جيدًا وقدّم بيانات موثوقة وفي الوقت المناسب لإجراء تدخلات الصحة العامة. قد يكون هذا النظام منصة مفيدة لرصد المتلازمات المرضية وعمليات الرصد في المختبرات في المواقع الأخرى قليلة الموارد وذلك بسبب مرونة هذا النظام وتكاليفه المعقولة بشكل عام.. 对流感监测系统的评估不足，尤其是在非洲。.. 在 2007 年以前，马达加斯加的流感监测系统仅在塔那那利佛运行，并且观察结果无法外推到整个国家。.. 截止 2014 年，该系统覆盖全国 34 个哨点。 我们在 12 个哨点采集了鼻咽和/或口咽样本并进行了流感病毒检测。 在 2009 年至 2014 年期间，我们发现了 177 718 宗发热病例，其中 25 809 (14.5%) 宗被归类为流感样疾病病例。 在进行流感病毒检测的 9192 个流感样疾病患者的样本中，3573 (38.9%) 个样本的检测结果呈阳性。 所有评估指标下的数据质量均超过 90%，并且系统在其可接受性、简单性和稳定性方面似乎也非常卓越。 然而，样本采集需要改进。.. 马达加斯加流感监测系统运行情况良好，并且为公共卫生干预提供可靠、及时的数据。 鉴于其灵活性和总体适中的成本，该系统可能会成为其他资源匮乏的地区进行综合征监测和实验室监测的有用平台。.. Неудовлетворительная оценка систем эпиднадзора за гриппом, особенно в Африке.. До 2007 года система эпиднадзора за гриппом на Мадагаскаре действовала только в Антананариву и полученные результаты наблюдений было невозможно экстраполировать на всю страну.. К 2014 году система охватывала 34 поста наблюдения по всей стране. На 12 постах были отобраны и протестированы на наличие вируса гриппа мазки из носоглотки и/или ротоглотки. В период с 2009 по 2014 год было выявлено 177 718 случаев лихорадки, 25 809 (14,5%) из этих случаев были классифицированы как случаи гриппоподобных заболеваний. Из 9192 проб, взятых у пациентов с гриппоподобными заболеваниями и протестированных на наличие вирусов гриппа, 3573 (38,9%) дали положительный результат. Качество данных для всех оцениваемых показателей было классифицировано как превышающее 90%. Система продемонстрировала хорошие показатели с точки зрения своей приемлемости, простоты и стабильности. Тем не менее отбор проб нуждается в улучшении.. Система эпиднадзора за гриппом в Мадагаскаре хорошо зарекомендовала себя и позволяла получать надежные и своевременные данные для мероприятий в области общественного здравоохранения. С учетом гибкости и умеренной стоимости этой системы она может стать полезной платформой для синдромного и лабораторного наблюдения в условиях ограниченности ресурсов.

Topics: Data Accuracy; Humans; Influenza, Human; Madagascar; Nasopharynx; Oropharynx; Program Evaluation; Sentinel Surveillance; Time Factors

Influenza immunization still poses a critical challenge globally and specifically for tropical regions due to their complex influenza circulation pattern. Tropical regions should select the WHO's Northern Hemisphere or Southern Hemisphere recommended vaccine composition based on local surveillance. Analyses of influenza immunization effectiveness have neglected to account for the proportion of circulating viruses prevented from causing infection each year. We investigate this question for Madagascar, where influenza vaccines are not widely available.. Seventy-eight Malagasy influenza strains characterized from 2002 to 2014 were challenged with hypothetical scenarios in which the WHO's Northern Hemisphere and Southern Hemisphere recommended vaccine compositions were provided to the population. Match between circulating and vaccine strains was determined by haemagglutination inhibition assays. Strain-specific positive matches were scored assuming 9 months of protection, and scenarios incorporated vaccine delays from zero to 5 months.. Malagasy influenza strains matched 54% and 44%, respectively, with the Northern Hemisphere and Southern Hemisphere recommended vaccine strains when the vaccine was delivered as soon as available. The matching values further decreased when additional delivery and application delays were considered. Differences between recommended compositions were not statistically significant.. Our results showed matching with the Northern Hemisphere vaccine barely above 50%, even in the more favourable scenario. This suggests that if implemented, routine influenza vaccines would not provide an optimal protection against half of the influenza strains circulating in any epidemic season of Madagascar. We suggest that this limitation in influenza vaccine efficacy deserves greater attention, and should be considered in cost/benefit analyses of national influenza immunization programmes.

Topics: Health Planning Guidelines; Hemagglutination Inhibition Tests; Humans; Immunization Programs; Influenza A virus; Influenza Vaccines; Influenza, Human; Madagascar; Seasons; Vaccination; World Health Organization

Topics: Adult; Americas; Disease Outbreaks; Female; Humans; Influenza A virus; Influenza, Human; Lassa Fever; Madagascar; Male; Nigeria; Plague; Zika Virus Infection

The seasonal drivers of influenza activity remain debated in tropical settings where epidemics are not clearly phased. Antananarivo is a particularly interesting case study because it is in Madagascar, an island situated in the tropics and with quantifiable connectivity levels to other countries.. We aimed at disentangling the role of environmental forcing and population fluxes on influenza seasonality in Madagascar.. We compiled weekly counts of laboratory-confirmed influenza-positive specimens for the period 2002 to 2012 collected in Antananarivo, with data available from sub-Saharan countries and countries contributing most foreign travelers to Madagascar. Daily climate indicators were compiled for the study period.. Overall, influenza activity detected in Antananarivo predated that identified in temperate Northern Hemisphere locations. This activity presented poor temporal matching with viral activity in other countries from the African continent or countries highly connected to Madagascar excepted for A(H1N1)pdm09. Influenza detection in Antananarivo was not associated with travel activity and, although it was positively correlated with all climatic variables studied, such association was weak.. The timing of influenza activity in Antananarivo is irregular, is not driven by climate, and does not align with that of countries in geographic proximity or highly connected to Madagascar. This work opens fresh questions regarding the drivers of influenza seasonality globally particularly in mid-latitude and less-connected regions to tailor vaccine strategies locally.

Topics: Climate; Epidemics; Humans; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Influenza B virus; Influenza Vaccines; Influenza, Human; Madagascar; Seasons; Sentinel Surveillance; Time Factors; Travel

It is difficult to assess the mortality burden of influenza epidemics in tropical countries. Until recently, the burden of influenza was believed to be negligible in Africa. We assessed the impact of the 2009 influenza epidemic on mortality in Madagascar by conducting Poisson regression analysis on mortality data from the deaths registry, after the first wave of the 2009 A(H1N1) virus pandemic. There were 20% more human deaths than expected in Antananarivo, Madagascar in November 2009, with excess mortality in the ⩾50 years age group (relative risk 1·41). Furthermore, the number of deaths from pulmonary disease was significantly higher than the number of deaths from other causes during this pandemic period. These results suggest that the A(H1N1) 2009 virus pandemic may have been accompanied by an increase in mortality.

Topics: Adolescent; Adult; Age Factors; Aged; Child; Humans; Influenza A Virus, H1N1 Subtype; Influenza, Human; Lung Diseases; Madagascar; Middle Aged; Pandemics; Regression Analysis; Risk

The revision of the International Health Regulations (IHR) and the threat of influenza pandemics and other disease outbreaks with a major impact on developing countries have prompted bolstered surveillance capacity, particularly in low-resource settings.. Surveillance tools with well-timed, validated data are necessary to strengthen disease surveillance. In 2007 Madagascar implemented a sentinel surveillance system for influenza-like illness (ILI) based on data collected from sentinel general practitioners.. Before 2007, Madagascar's disease surveillance was based on the passive collection and reporting of data aggregated weekly or monthly. The system did not allow for the early identification of outbreaks or unexpected increases in disease incidence.. An innovative case reporting system based on the use of cell phones was launched in March 2007. Encrypted short message service, which costs less than 2 United States dollars per month per health centre, is now being used by sentinel general practitioners for the daily reporting of cases of fever and ILI seen in their practices. To validate the daily data, practitioners also report epidemiological and clinical data (e.g. new febrile patient's sex, age, visit date, symptoms) weekly to the epidemiologists on the research team using special patient forms.. Madagascar's sentinel ILI surveillance system represents the country's first nationwide "real-time" surveillance system. It has proved the feasibility of improving disease surveillance capacity through innovative systems despite resource constraints. This type of syndromic surveillance can detect unexpected increases in the incidence of ILI and other syndromic illnesses.

Topics: Child; Confidence Intervals; Data Collection; Developing Countries; Disease Outbreaks; Female; Humans; Influenza Vaccines; Influenza, Human; Madagascar; Male; Pandemics; Public Health Practice; Risk Assessment; Sentinel Surveillance; Text Messaging

The influenza A(H1N1)pdm09 virus has been a challenge for public health surveillance systems in all countries. In Antananarivo, the first imported case was reported on August 12, 2009. This work describes the spread of A(H1N1)pdm09 in Madagascar.. The diffusion of influenza A(H1N1)pdm09 in Madagascar was explored using notification data from a sentinel network. Clinical data were charted to identify peaks at each sentinel site and virological data was used to confirm viral circulation.. From August 1, 2009 to February 28, 2010, 7,427 patients with influenza-like illness were reported. Most patients were aged 7 to 14 years. Laboratory tests confirmed infection with A(H1N1)pdm09 in 237 (33.2%) of 750 specimens. The incidence of patients differed between regions. By determining the epidemic peaks we traced the diffusion of the epidemic through locations and time in Madagascar. The first peak was detected during the epidemiological week 47-2009 in Antananarivo and the last one occurred in week 07-2010 in Tsiroanomandidy.. Sentinel surveillance data can be used for describing epidemic trends, facilitating the development of interventions at the local level to mitigate disease spread and impact.

Topics: Adolescent; Adult; Child; Child, Preschool; Disease Outbreaks; Epidemics; Female; Humans; Incidence; Infant; Influenza A Virus, H1N1 Subtype; Influenza, Human; Madagascar; Male; Public Health Surveillance; Sentinel Surveillance; Young Adult

Madagascar was one of the first African countries to be affected by the 2009 pandemic of influenza A virus subtype H1N1 [A(H1N1)pdm2009] infection. The outbreak started in the capital city, Antananarivo, and then spread throughout the country from October 2009 through February 2010.. Specimens from patients presenting with influenza-like illness were collected and shipped to the National Influenza Center in Madagascar for analyses, together with forms containing patient demographic and clinical information.. Of the 2303 specimens tested, 1016 (44.1%) and 131 (5.7%) yielded A(H1N1)pdm09 and seasonal influenza virus, respectively. Most specimens (42.0%) received were collected from patients <10 years old. Patients <20 years old were more likely than patients >50 years old to be infected with A(H1N1)pdm09 (odds ratio, 2.1; 95% confidence interval, 1.7-2.6; P < .01). Although phylogenetic analyses of A(H1N1)pdm09 suggested multiple introductions of the virus into Madagascar, no antigenic differences between A(H1N1)pdm09 viruses recovered in Madagascar and those that circulated worldwide were observed.. The high proportion of respiratory specimens positive for A(H1N1)pdm09 is consistent with a widespread transmission of the pandemic in Madagascar. The age distribution of cases of A(H1N1)pdm09 infection suggests that children and young adults could be targeted for interventions that aim to reduce transmission during an influenza pandemic.

Topics: Adolescent; Adult; Age Distribution; Aged; Child; Child, Preschool; Female; Genotype; Humans; Infant; Influenza A Virus, H1N1 Subtype; Influenza, Human; Madagascar; Male; Middle Aged; Molecular Epidemiology; Molecular Sequence Data; Pandemics; Phylogeny; RNA, Viral; Sequence Analysis, DNA; Young Adult

Although recent work has described the spatiotemporal diffusion of influenza viruses worldwide, comprehensive data on spatiotemporal patterns of influenza from the African continent and Madagascar are still lacking.. National Influenza Centers from 5 countries-Cameroon, Côte d'Ivoire, Madagascar, Niger, and Senegal--collected specimens from patients presenting with influenza-like illness who visited sentinel surveillance clinics during a 2-year period (2008-2009). Isolates were genetically and antigenically characterized.. Overall, 8312 specimens were tested. Seasonal influenza A virus subtypes H1N1 and H3N2 and influenza B viruses were detected in 329, 689, and 148 specimens, respectively. In 2009, pandemic influenza A virus subtype H1N1 was detected in Madagascar most commonly (98.5% of cases). Influenza activity was either significant year-round or occurred during a specific period of the year in the African countries we evaluated.. Our results demonstrate that, from Madagascar to Senegal, the epidemiologic and virologic characteristics of influenza viruses are diverse in terms of spatiotemporal circulation of the different virus types, subtypes, and strains. Our data highlight the importance of country-specific surveillance and of data and virus sharing, and they provide a rational basis to aid policy makers to develop strategies, such as vaccination at the right moment and with the right formulation, aimed at reducing the disease burden in Africa and Madagascar.

Topics: Africa; Antigens, Viral; Genetic Variation; Humans; Influenza, Human; International Cooperation; Madagascar; Orthomyxoviridae; RNA, Viral; Sentinel Surveillance; Time Factors; Topography, Medical

In Madagascar, despite an influenza surveillance established since 1978, little is known about the etiology and prevalence of viruses other than influenza causing influenza-like illnesses (ILIs).. From July 2008 to June 2009, we collected respiratory specimens from patients who presented ILIs symptoms in public and private clinics in Antananarivo (the capital city of Madagascar). ILIs were defined as body temperature ≥38°C and cough and at least two of the following symptoms: sore throat, rhinorrhea, headache and muscular pain, for a maximum duration of 3 days. We screened these specimens using five multiplex real time Reverse Transcription and/or Polymerase Chain Reaction assays for detection of 14 respiratory viruses. We detected respiratory viruses in 235/313 (75.1%) samples. Overall influenza virus A (27.3%) was the most common virus followed by rhinovirus (24.8%), RSV (21.2%), adenovirus (6.1%), coronavirus OC43 (6.1%), influenza virus B (3.9%), parainfluenza virus-3 (2.9%), and parainfluenza virus-1 (2.3%). Co-infections occurred in 29.4% (69/235) of infected patients and rhinovirus was the most detected virus (27.5%). Children under 5 years were more likely to have one or more detectable virus associated with their ILI. In this age group, compared to those ≥5 years, the risk of detecting more than one virus was higher (OR = 1.9), as was the risk of detecting of RSV (OR = 10.1) and adenovirus (OR = 4.7). While rhinovirus and adenovirus infections occurred year round, RSV, influenza virus A and coronavirus OC43 had defined period of circulation.. In our study, we found that respiratory viruses play an important role in ILIs in the Malagasy community, particularly in children under 5 years old. These data provide a better understanding of the viral etiology of outpatients with ILI and describe for the first time importance of these viruses in different age group and their period of circulation.

Topics: Adolescent; Adult; Child; Child, Preschool; Demography; Female; Humans; Incidence; Infant; Infant, Newborn; Influenza, Human; Madagascar; Male; Seasons; Virus Physiological Phenomena; Viruses; Young Adult

In October 2009, the first outbreak of pandemic influenza A(H1N1) 2009 virus  in Madagascar occurred at a school in Antananarivo. Among the first 12 cases, five were reported in boarding pupils at the school. The school closed 10 days into the outbreak. Mass oseltamivir prophylactic treatment was used to contain the outbreak. This study aimed to determine the transmission of infection among boarding school pupils and to evaluate the adverse effects of oseltamivir chemoprophylactic treatment and their impact on compliance.. After conducting an initial investigation of the outbreak we administered a questionnaire to 132 boarders who were present after the school re-opened. Questions addressed symptoms of influenza-like illness, compliance with chemoprophylaxis, and adverse effects.. Of 59 boarders, 20 (45.0%) had confirmed pandemic influenza A (H1N1) infection. Among the asymptomatic boarders, compliance with oseltamivir chemoprophylaxis was moderate: 56.2% took the full 10-day course, and 66.9% completed at least seven days. In contrast, among symptomatic boarders, only two did not take the full course of oseltamivir. Fifty percent of the boarders receiving oseltamivir experienced symptoms such as fatigue (38.7%), difficulty concentrating (22.6%) and headaches (19.4%). Bad compliance was not associated with adverse effects.. Since the symptoms of pandemic influenza A(H1N1) 2009 virus were generally mild, the burden of adverse effects must be considered when deciding on mass oseltamivir chemoprophylaxis among teenagers.

Topics: Adolescent; Antiviral Agents; Chemoprevention; Disease Outbreaks; Female; Humans; Influenza A Virus, H1N1 Subtype; Influenza, Human; Madagascar; Male; Medication Adherence; Oseltamivir; Schools; Students; Surveys and Questionnaires

As part of an ongoing study focused on the discovery of anti-influenza agents from plants, four new (1-4) and 10 known (5-14) C-methylated flavonoids were isolated from a methanol extract of Cleistocalyx operculatus buds using an influenza H1N1 neuraminidase inhibition assay. Compounds 4, 7, 8, and 14, with a chalcone skeleton, showed significant inhibitory effects on the viral neuraminidases from two influenza viral strains, H1N1 and H9N2. Compound 4 showed the strongest inhibitory activity against the neuraminidases from novel influenza H1N1 (WT) and oseltamivir-resistant novel H1N1 (H274Y mutant) expressed in 293T cells with IC50 values of 8.15 ± 1.05 and 3.31 ± 1.34 μM, respectively. Compounds 4, 7, 8, and 14 behaved as noncompetitive inhibitors in the kinetic studies. These results indicate that C-methylated flavonoids from C. operculatus have the potential to be developed as neuraminidase inhibitors for novel influenza H1N1.

Topics: Antiviral Agents; Flavonoids; HEK293 Cells; Humans; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H9N2 Subtype; Influenza, Human; Inhibitory Concentration 50; Kinetics; Molecular Structure; Myrtaceae; Neuraminidase; Oseltamivir

The purpose of this paper is to actualize the historical data on influenza in Madagascar. The first outbreak of flu probably occurred in 1890. The first epidemic fully described was in 1893. Between 1890 and 1957, 11 outbreaks of influenza were registered. Since 1978, the unit of virology of the Institut Pasteur de Madagascar is the National Reference Center of the World Health Organization for influenza in Madagascar. Between 1975 and 2002, 12 epidemics of flu were registered confirmed by viral isolation. Madagascan terms used to design fever diseases are discussed.

Topics: Academies and Institutes; Disease Outbreaks; History, 20th Century; Humans; Influenza, Human; Madagascar; Population Surveillance; Registries; Semantics; Virology; Virus Cultivation; World Health Organization

The "Institut Pasteur de Madagascar" virology laboratory is the National WHO Centre for Influenza surveillance in Madagascar. On this surveillance collaborate the Ministry of Health with 9 sentinel centres. In the present article, the authors relate the results of influenza surveillance in Antananarivo between 1995 and 2002. Among 6341 patients with nasal and/or pharyngeal swabs, influenza virus were isolated from 427 patients (6.7%): 307 (68.4%) influenza virus A (H3N2), 124 (27.1%) influenza virus B, 8 (4.0%) influenza virus A (H1N1). The virus had been continually spreading all year long. The weak and the strong points of the influenza sentinel surveillance are also discussed in order to ameliorate the collection processes of influenzal and respiratory morbidity data.

Topics: Data Collection; Developing Countries; Disease Outbreaks; Humans; Incidence; Influenza A virus; Influenza B virus; Influenza, Human; Madagascar; Morbidity; Nasopharynx; Needs Assessment; Population Surveillance; Public Health; Seasons; Total Quality Management; Urban Health; Virus Cultivation

In mid-July 2002, Madagascar health authorities were notified of a substantial number of deaths attributed to acute respiratory illness (ARI) in the village of Sahafata (population: 2,160), located in the rural highlands of Fianarantsoa Province, southeastern Madagascar (Figure 1). This region is approximately 450 km (280 miles) south of the capital Antananarivo. The Madagascar Ministry of Health (MOH) and the Institut Pasteur, Madagascar (IPM) initiated an investigation, which found an attack rate of 70% for ARI, with 27 deaths in Sahafata. Pharyngeal swab specimens were collected from ill persons for viral culture. Of the four influenza A viruses that were isolated at IPM, two were identified as type A (H3N2) viruses. In late July, health authorities investigated a similar outbreak in Ikongo District, Fianarantsoa Province. In August, MOH requested assistance from the World Health Organization (WHO) and CDC in investigating the outbreak. In response, an international team of experts from CDC; Institut de Veille Sanitaire, France; Institut Pasteur, France; and WHO was mobilized from the Global Outbreak Alert and Response Network; the team arrived in Madagascar on August 14. This report summarizes the preliminary epidemiologic and virologic findings, which suggest that the outbreak was attributable to influenza A (H3N2) viruses. Further surveillance and research about the epidemiology of influenza in Madagascar is planned.

Topics: Disease Outbreaks; Humans; Influenza, Human; Madagascar

Topics: Adolescent; Adult; Age Distribution; Aged; Child; Child, Preschool; Developing Countries; Disease Outbreaks; Female; Humans; Incidence; Influenza A virus; Influenza B virus; Influenza, Human; Madagascar; Male; Middle Aged; Population Surveillance; Risk Factors; Sex Distribution; Survival Rate

Topics: Disease Outbreaks; Europe; Humans; Influenza, Human; Madagascar; Orthomyxoviridae; Population Surveillance; Species Specificity

Preliminary investigation found that a large outbreak of influenza-like illness occurred in Madagascar during July-August 2002, with 30 304 cases and 754 deaths reported. Most cases were reported from the highland regions of Fianarantsoa Province, in centre Madagascar. The majority of the cases lived in rural areas, and children under five years and adults 60 years and older were the most affected. The outbreak was attributable to an A/Panama/2007/99-like (H3N2) virus, which has been circulating worldwide for several years.

Topics: Adult; Aged; Child; Disease Outbreaks; Humans; Influenza, Human; Madagascar; Middle Aged; Orthomyxoviridae; Population Surveillance; Survival Rate

62 rhinopharingeal samples from malagasy children, aged of 6 days to 14 years old, hospitalized because of acute respiratory infections, with doubtful viral etiology case, during June to August 1992, at the "Hôpital des Enfants" in Antananarivo, were examined by two methods: inoculation by embryonned eggs and inoculation by MDCK cells. 24.1% of the samples were positive. The repartition of the cases by age and by sex were studied. The children aged of 1 to 12 months were the most affected with 65.7% of all cases (male: 60%, female: 40%). One subtype was detected: A(H3N2).

Topics: Acute Disease; Adolescent; Age Distribution; Child; Child, Preschool; Cough; Dyspnea; Fever; Hemagglutination Inhibition Tests; Hospitalization; Hospitals, Pediatric; Humans; Infant; Infant, Newborn; Influenza A virus; Influenza, Human; Madagascar; Morbidity; Population Surveillance; Rhinitis; Seasons; Sex Distribution; Virus Cultivation

The authors relate the 1992 results of influenza surveillance in Antananarivo. 24 influenza virus A (H3N2) strains were isolated from 467 pharyngeal swabs. The virus had been continually spreading from January to September, with a peak in July, along with some monthly sporadic isolations. The highest respiratory morbidity was observed in June and July. The collection processes of influenzal and respiratory morbidity statistics are also discussed in order to standardize data and to define the real impact of influenza and other acute affections of respiratory tracts on the population.

Topics: Acute Disease; Adolescent; Adult; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Influenza A virus; Influenza B virus; Influenza, Human; Madagascar; Male; Morbidity; Pharynx; Population Surveillance; Seasons; Urban Population

The authors report results of epidemiological survey of influenza in TANANARIVE. This survey is based on respiratory morbidity observed in an interprofessional health center, and virus isolation. Two viruses have circulated in 1989: B virus (B/VICTORIA/2/87) during first half-year, and A: A/VICTORIA/36/88 (H1N1) virus during dry season with a pick in November. Influenzae has been responsible of grouped sporadic cases without epidemic diffusion.

Topics: Adolescent; Adult; Child; Child, Preschool; Hemagglutination Tests; Humans; Infant; Influenza A virus; Influenza B virus; Influenza, Human; Madagascar; Morbidity; Population Surveillance; Seasons; Serotyping; Urban Population

Topics: Adolescent; Adult; Child; Child, Preschool; Humans; Influenza A virus; Influenza B virus; Influenza, Human; Madagascar; Middle Aged

Topics: Adolescent; Adult; Age Factors; Child; Child, Preschool; Female; Humans; Infant; Influenza A virus; Influenza, Human; Madagascar; Male; Population Surveillance; Seasons

Topics: Alphavirus; Animals; Humans; Influenza, Human; Lemur; Lemuridae; Madagascar

Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Influenza A virus; Influenza, Human; Madagascar; Male; Middle Aged

Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Disease Outbreaks; Female; Humans; Infant; Influenza A virus; Influenza A Virus, H3N2 Subtype; Influenza, Human; Madagascar; Male; Middle Aged