clove and Zoonoses

Madagascar has just emerged from the grip of an acute urban pneumonic plague outbreak, which began in August 2017, before the usual plague season of October-April and outside the traditional plague foci in the northern and central highlands. The World Health Organization reported a total of 2417 confirmed, probable and suspected cases, including 209 deaths between 1 August and 26 November 2017. The severity and scope of this outbreak, which has affected those in higher socioeconomic groups as well as those living in poverty, along with factors including the potential for use of multi-drug-resistant strains of plague in bioterrorism, highlights the ongoing threat posed by this ancient disease. Factors likely to have contributed to transmission include human behaviour, including burial practices and movement of people, poor urban planning leading to overcrowding and ready transmission by airborne droplets, climatic factors and genomic subtypes. The outbreak demonstrates the importance of identifying targeted pneumonic plague therapies and of developing vaccines that can be administered in planned programmes in developing countries such as Madagascar where plague is endemic. The dominance of pneumonic plague in this outbreak suggests that we need to focus more urgently on the danger of person-to-person transmission, as well as the problem of transmission of plague from zoonotic sources.

Topics: Animals; Disease Outbreaks; Disease Reservoirs; Endemic Diseases; Humans; Lung; Madagascar; Plague; Rats; Yersinia pestis; Zoonoses

Cysticercosis caused by accidental ingestion of eggs of Taenia solium is spreading all over the world through globalization and is one of the most neglected, neglected tropical diseases (NTDs) or neglected zoonotic diseases (NZDs). In the present study, the reason why T. solium cysticercosis has been neglected is discussed at first, and followed with an overview on the most recent advances and perspectives in molecular approaches for epidemiology of T. solium taeniasis/cysticercosis, since although taeniasis does not constitute recognized zoonoses, transmission and complete development are dependent on human definitive hosts. Main topics are discussions on (1) the two, Asian and Afro/American, genotypes of T. solium, (2) comparative analysis of mitochondrial (haploid) and nuclear (diploid) genes, and (3) the presence of hybrids of these two genotypes which indicates out-crossing of two genotypes in hermaphrodite tapeworms in Madagascar. Additional topics are on (4) the usefulness of phylogeographic analyses to discuss where the infection was acquired from, and (5) miscellaneous unsolved topics around these genetic diversity of T. solium.

Topics: Animals; Cysticercosis; DNA, Mitochondrial; DNA, Protozoan; Genotype; Haplotypes; Humans; Madagascar; Molecular Epidemiology; Phylogeny; Swine; Swine Diseases; Taenia solium; Zoonoses

Rift Valley fever (RVF) is a viral zoonotic disease occurring throughout Africa, the Arabian Peninsula, and Madagascar. The disease is caused by a Phlebovirus (RVF virus [RVFV]) transmitted to vertebrate hosts through the bite of infected mosquitoes. In Madagascar, the first RVFV circulation was reported in 1979 based on detection in mosquitoes but without epidemic episode. Subsequently, two outbreaks occurred: the first along the east coast and in the central highlands in 1990 and 1991 and the most recent along the northern and eastern coasts and in the central highlands in 2008 and 2009. Despite the presence of 24 mosquitoes species potentially associated with RVFV transmission in Madagascar, little associated entomological information is available. In this review, we list the RVFV vector, Culex antennatus, as well as other taxa as candidate vector species. We discuss risk factors from an entomological perspective for the re-emergence of RVF in Madagascar.

Topics: Animals; Culicidae; Disease Outbreaks; Female; Humans; Insect Vectors; Madagascar; Rift Valley Fever; Rift Valley fever virus; Risk Factors; Species Specificity; Zoonoses

Hydatid disease, due to the larval stage of Echinococcus granulosus, is described for the second time at liver level, in Madagascar. Even with a low level of endemic animal disease and an uncontrolled population of stray dogs, the human parasitosis is very rare in Madagascar. It is interesting to note that, since a hundred of years, the epidemiological status of this Zoonosis has not really changed in the great island.

Topics: Adult; Animals; Dog Diseases; Dogs; Echinococcosis, Hepatic; Echinococcus; Female; Humans; Larva; Madagascar; Zoonoses

Topics: Animals; Humans; Madagascar; Zoonoses

Plague is a zoonotic disease caused by the bacterium Yersinia pestis, highly prevalent in the Central Highlands, a mountainous region in the center of Madagascar. After a plague-free period of over 60 years in the northwestern coast city of Mahajanga, the disease reappeared in 1991 and caused several outbreaks until 1999. Previous research indicates that the disease was reintroduced to the city of Mahajanga from the Central Highlands instead of reemerging from a local reservoir. However, it is not clear how many reintroductions occurred and when they took place.. In this study we applied a Bayesian phylogeographic model to detect and date migrations of Y. pestis between the two locations that could be linked to the re-emergence of plague in Mahajanga. Genome sequences of 300 Y. pestis strains sampled between 1964 and 2012 were analyzed. Four migrations from the Central Highlands to Mahajanga were detected. Two resulted in persistent transmission in humans, one was responsible for most of the human cases recorded between 1995 and 1999, while the other produced plague cases in 1991 and 1992. We dated the emergence of the Y. pestis sub-branch 1.ORI3, which is only present in Madagascar and Turkey, to the beginning of the 20th century, using a Bayesian molecular dating analysis. The split between 1.ORI3 and its ancestor lineage 1.ORI2 was dated to the second half of the 19th century.. Our results indicate that two independent migrations from the Central Highlands caused the plague outbreaks in Mahajanga during the 1990s, with both introductions occurring during the early 1980s. They happened over a decade before the detection of human cases, thus the pathogen likely survived in wild reservoirs until the spillover to humans was possible. This study demonstrates the value of Bayesian phylogenetics in elucidating the re-emergence of infectious diseases.

Topics: Animals; Bayes Theorem; Humans; Madagascar; Phylogeny; Phylogeography; Yersinia pestis; Zoonoses

Plague is a re-emerging zoonotic disease and a major public health concern in several portions of the world, especially in Madagascar. We report on the presence of different subtypes of Yersinia pestis co-occurring in the same locality. After confirmation of a human plague case in Ambohitromby Commune (Ankazobe District) via isolation of Y. pestis, we undertook small mammal trapping to identify the circulation of Y. pestis amongst rodents in this locality; blood samples were collected from rodents for seroprevalence analysis. Of the 60 individuals of Rattus rattus captured, one yielded an isolate of Y. pestis, 13 others were positive for F1 antigen of Y. pestis using a rapid diagnostic test, and 4 were PCR positive targeting the caf1 and pla genes; 28/60 (46.7%) of the captured R. rattus were seropositive for Y. pestis. Whole-genome SNP analyses revealed that the two isolates obtained from the human case, and the R. rattus belonged to two different subtypes of Y. pestis (s05 and s13, respectively) that were circulating concurrently in Ambohitromby in 2016. Three Y. pestis subtypes (s03, s05 and s13) have now been isolated from Ambohitromby. Subtype s05 had been persisting there for >10 years but one or both of the other subtypes may have been introduced from the Central Highlands region as they were not observed in previous years (s13) or only observed once previously (s03). High seroprevalence against Y. pestis in R. rattus suggests that a portion of the local murine population may have acquired resistance to Y. pestis. Future research should focus on genomically characterizing Y. pestis strains circulating in Ankazobe District and other plague-endemic regions of Madagascar to better understand the overall phylogeography of Y. pestis.

Topics: Animals; Madagascar; Mammals; Mice; Plague; Rats; Rodent Diseases; Seroepidemiologic Studies; Yersinia pestis; Zoonoses

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Topics: Animals; Chiroptera; Genome, Viral; Glycoproteins; Henipavirus; Henipavirus Infections; Humans; Madagascar; Nipah Virus; Phylogeny; Urine; Zoonoses

We conducted a national human serologic study of a hantavirus detected in Madagascar rodents using a commercial kit and a new ELISA targeting the virus. Our results suggest a conservative estimate of 2.7% (46/1,680) IgG seroprevalence. A second single-district study using the new ELISA revealed a higher prevalence (7.2%; 10/139).

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Child; Child, Preschool; Disease Reservoirs; Female; Hantavirus Infections; Humans; Madagascar; Male; Mice; Middle Aged; Prevalence; Retrospective Studies; Young Adult; Zoonoses

Human activities can increase or decrease risks of acquiring a zoonotic disease, notably by affecting the composition and abundance of hosts. This study investigated the links between land use and infectious disease risk in northeast Madagascar, where human subsistence activities and population growth are encroaching on native habitats and the associated biota. We collected new data on pathogenic Leptospira, which are bacteria maintained in small mammal reservoirs. Transmission can occur through close contact, but most frequently through indirect contact with water contaminated by the urine of infected hosts. The probability of infection and prevalence was compared across a gradient of natural moist evergreen forest, nearby forest fragments, flooded rice and other types of agricultural fields, and in homes in a rural village. Using these data, we tested specific hypotheses for how land use alters ecological communities and influences disease transmission. The relative abundance and proportion of exotic species was highest in the anthropogenic habitats, while the relative abundance of native species was highest in the forested habitats. Prevalence of Leptospira was significantly higher in introduced compared to endemic species. Lastly, the probability of infection with Leptospira was highest in introduced small mammal species, and lower in forest fragments compared to other habitat types. Our results highlight how human land use affects the small mammal community composition and in turn disease dynamics. Introduced species likely transmit Leptospira to native species where they co-occur, and may displace the Leptospira species naturally occurring in Madagascar. The frequent spatial overlap of people and introduced species likely also has consequences for public health.

Topics: Animals; Ecology; Ecosystem; Forests; Humans; Introduced Species; Leptospira; Leptospirosis; Madagascar; Mammals; Prevalence; Zoonoses

In developing countries, estimates of the prevalence and diversity of Leptospira infections in livestock, an important but neglected zoonotic pathogen and cause of livestock productivity loss, are lacking. In Madagascar, abattoir sampling of cattle and pigs demonstrated a prevalence of infection of 20% in cattle and 5% in pigs by real-time PCR. In cattle, amplification and sequencing of the Leptospira-specific lfb1 gene revealed novel genotypes, mixed infections of two or more Leptospira species and evidence for potential transmission between small mammals and cattle. Sequencing of the secY gene demonstrated genetic similarities between Leptospira detected in Madagascar and, as yet, uncultured Leptospira strains identified in Tanzania, Reunion and Brazil. Detection of Leptospira DNA in the same animal was more likely in urine samples or pooled samples from four kidney lobes relative to samples collected from a single kidney lobe, suggesting an effect of sampling method on detection. In pigs, no molecular typing of positive samples was possible. Further research into the epidemiology of livestock leptospirosis in developing countries is needed to inform efforts to reduce human infections and to improve livestock productivity.

Topics: Abattoirs; Africa; Animals; Cattle; Cattle Diseases; Coinfection; Developing Countries; Disease Reservoirs; Genotype; Leptospira; Leptospirosis; Livestock; Madagascar; Phylogeny; Prevalence; Swine; Swine Diseases; Zoonoses

Zoonosis calls for a multispecies approach to medical semiotics, a method involving the decipherment of outward symptoms and the construction of narrative. In Madagascar, early detection of bubonic plague outbreaks relies on sightings of sick and dead rats. However, people most vulnerable to plague often do not perceive warning signs, and plague symptoms do not always present in rat and human bodies. In August 2015, a plague outbreak killed 10 residents of a rural hamlet in the central highlands. To reconstruct the transmission chain, scientists elicited survivors' memories of dead rats in the vicinity. Not only were these clues imperceptible to most, but residents had also constructed an alternative outbreak narrative based on different evidence. Stark health disparities, a lack of historical memory of the plague, and genetic adaptations of rats and plague bacteria have created a problem of "semiotic cluelessness" that complicates outbreak control measures and increases mortality.

Topics: Animals; Anthropology, Medical; Disease Outbreaks; Humans; Madagascar; Narration; Plague; Rats; Zoonoses

Rift Valley fever (RVF) is a re-emerging zoonotic disease responsible for major losses in livestock production, with negative impact on the livelihoods of both commercial and resource-poor farmers in sub-Sahara African countries. The disease remains a threat in countries where its mosquito vector thrives. Outbreaks of RVF usually follow weather conditions which favour increase in mosquito populations. Such outbreaks are usually cyclical, occurring every 10-15 years. Recent outbreaks of the disease in South Africa have occurred unpredictably and with increased frequency. In 2008, outbreaks were reported in Mpumalanga, Limpopo and Gauteng provinces, followed by 2009 outbreaks in KwaZulu-Natal, Mpumalanga and Northern Cape provinces and in 2010 in the Eastern Cape, Northern Cape, Western Cape, North West, Free State and Mpumalanga provinces. By August 2010, 232 confirmed infections had been reported in humans, with 26 confirmed deaths.To investigate the evolutionary dynamics of RVF viruses (RVFVs) circulating in South Africa, we undertook complete genome sequence analysis of isolates from animals at discrete foci of the 2008-2010 outbreaks. The genome sequences of these viruses were compared with those of the viruses from earlier outbreaks in South Africa and in other countries. The data indicate that one 2009 and all the 2008 isolates from South Africa and Madagascar (M49/08) cluster in Lineage C or Kenya-1. The remaining of the 2009 and 2010 isolates cluster within Lineage H, except isolate M259_RSA_09, which is a probable segment M reassortant. This information will be useful to agencies involved in the control and management of Rift Valley fever in South Africa and the neighbouring countries.

Topics: Animals; Buffaloes; Cattle; Cattle Diseases; Computational Biology; Disease Outbreaks; Genome, Viral; Humans; Kenya; Madagascar; Mosquito Vectors; Phylogeny; Reassortant Viruses; Rift Valley Fever; Rift Valley fever virus; Sheep; Sheep Diseases; South Africa; Zoonoses

Leptospirosis is a zoonotic disease of global importance, especially in tropical countries. The current

Topics: Animals; Antibodies, Bacterial; Antigens, Bacterial; Cattle; Cattle Diseases; Leptospira; Leptospirosis; Madagascar; Seroepidemiologic Studies; Serogroup; Zoonoses

Two cases of meningitis caused by Streptococcus suis occurred in Madagascar, 1 in 2015 and 1 in 2016. We report the characterization of the novel sequence type, 834, which carried the mrp+/sly+/epf+ virulence marker and a mutation G→T at position 174, leading to a substitution mutS1 to mutS284.

Topics: Adult; Animals; Female; Genotype; Humans; Madagascar; Male; Meat; Meningitis, Bacterial; Middle Aged; Streptococcal Infections; Streptococcus suis; Swine; Young Adult; Zoonoses

The discovery and characterization of emerging tick-borne organisms are critical for global health initiatives to improve animal and human welfare (One Health). It is possible that unknown tick-borne organisms underlie a subset of undiagnosed illness in wildlife, domesticated species, and humans. Our study lends support to the One Health concept by highlighting the prevalence of three blood-borne organisms in wild lemurs living in close proximity to domesticated species and humans. Previously, our team identified three novel, presumably tick-borne, intravascular organisms, belonging to the genera Babesia, Borrelia, and Neoehrlichia, circulating in two of Madagascar's lemur species. Here, we extend our previous observation by developing a targeted molecular surveillance approach aimed at determining the prevalence of these organisms in lemurs. Using quantitative PCR, we provide Babesia, Borrelia, and Neoehrlichia prevalence data for 76 individuals comprising four lemur species located in eastern Madagascar. Our results indicate a high prevalence (96%) of Babesia across sampled individuals with lower prevalences for Neoehrlichia (36%) and Borrelia (14.5%). In light of our results, we recommend additional studies of these tick-borne organisms to determine pathogenicity and assess zoonotic potency to other animals and humans in Madagascar.

Topics: Animals; Babesia; Babesiosis; Borrelia; Humans; Ixodes; Lemur; Lyme Disease; Madagascar; One Health; Tick-Borne Diseases; Zoonoses

Brucellosis, Q fever and melioidosis are zoonoses, which can lead to pyrexia. These diseases are often under-ascertained and underreported because of their unspecific clinical signs and symptoms, insufficient awareness by physicians and public health officers and limited diagnostic capabilities, especially in low-resource countries. Therefore, the presence of Brucella spp., Coxiella burnetii and Burkholderia pseudomallei was investigated in Malagasy patients exhibiting febrile illness. In addition, we analyzed zebu cattle and their ticks as potential reservoirs for Brucella and C. burnetii, respectively. Specific quantitative real-time PCR assays (qPCRs) were performed on 1020 blood samples drawn from febrile patients. In total, 15 samples (1.5%) were Brucella-positive, mainly originating from patients without travel history, while DNA from C. burnetii and Bu. pseudomallei was not detected. Anti-C. burnetii antibodies were found in four out of 201 zebu serum samples (2%), whereas anti-Brucella antibodies could not be detected. Brucella DNA was detected in a single zebu sample. Three out of 330 ticks analyzed (1%) were positively tested for C. burnetii DNA but with high Ct values in the qPCR assay. Our data suggest that zebus as well as Amblyomma and Boophilus ticks have to be considered as a natural reservoir or vector for C. burnetii, but the risk of cattle-to-human transmission is low. Since bovine brucellosis does not seem to contribute to human infections in Madagascar, other transmission routes have to be assumed.

Topics: Animals; Antibodies, Bacterial; Brucella; Brucellosis; Cattle; Coxiella burnetii; Fever; Humans; Madagascar; Melioidosis; Q Fever; Real-Time Polymerase Chain Reaction; Zoonoses

Identifying key reservoirs for zoonoses is crucial for understanding variation in incidence. Plague re-emerged in Mahajanga, Madagascar in the 1990s but there has been no confirmed case since 1999. Here we combine ecological and genetic data, from during and after the epidemics, with experimental infections to examine the role of the shrew Suncus murinus in the plague epidemiological cycle. The predominance of S. murinus captures during the epidemics, their carriage of the flea vector and their infection with Yersinia pestis suggest they played an important role in the maintenance and transmission of plague. S. murinus exhibit a high but variable resistance to experimental Y. pestis infections, providing evidence of its ability to act as a maintenance host. Genetic analyses of the strains isolated from various hosts were consistent with two partially-linked transmission cycles, with plague persisting within the S. murinus population, occasionally spilling over into the rat and human populations. The recent isolation from a rat in Mahajanga of a Y. pestis strain genetically close to shrew strains obtained during the epidemics reinforces this hypothesis and suggests circulation of plague continues. The observed decline in S. murinus and Xenopsylla cheopis since the epidemics appears to have decreased the frequency of spillover events to the more susceptible rats, which act as a source of infection for humans. Although this may explain the lack of confirmed human cases in recent years, the current circulation of plague within the city highlights the continuing health threat.

Topics: Animals; Disease Outbreaks; Disease Reservoirs; Humans; Insect Vectors; Madagascar; Plague; Rats; Shrews; Xenopsylla; Yersinia pestis; Zoonoses

Zoonotic diseases are a looming threat to global populations, and nearly 75% of emerging infectious diseases can spread among wildlife, domestic animals and humans. A 'One World, One Health' perspective offers us an ideal framework for understanding and potentially mitigating the spread of zoonoses, and the island of Madagascar serves as a natural laboratory for conducting these studies. Rapid habitat degradation and climate change on the island are contributing to more frequent contact among humans, livestock and wildlife, increasing the potential for pathogen spillover events. Given Madagascar's long geographical isolation, coupled with recent and repeated introduction of agricultural and invasive species, it is likely that a number of circulating pathogens remain uncharacterized in lemur populations. Thus, it is imperative that new approaches be implemented for de novo pathogen discovery. To this end, we used non-targeted deep sequencing of blood transcriptomes from two species of critically endangered wild lemurs (Indri indri and Propithecus diadema) to characterize blood-borne pathogens. Our results show several undescribed vector-borne parasites circulating within lemurs, some of which may cause disease in wildlife, livestock and humans. We anticipate that advanced methods for de novo identification of unknown pathogens will have broad utility for characterizing other complex disease transmission systems.

Topics: Animals; Endangered Species; Gram-Negative Bacterial Infections; Lemur; Madagascar; Protozoan Infections, Animal; Transcriptome; Zoonoses

Epidemiological models often use information on host social contacts to predict the potential impact of infectious diseases on host populations and the efficiency of control measures. It can be difficult, however, to determine whether social contacts are actually meaningful predictors of transmission. We investigated the role of host social structure in the transmission of Escherichia coli in a wild population of primates, Verreaux's sifakas (Propithecus verreauxi). Using multilocus sequence typing (MLST), we compared genetic similarities between E. coli isolates from different individuals and groups to infer transmission pathways.. Correlation of social and transmission networks revealed that membership to the same group significantly predicted sharing of E. coli MLST sequence types (ST). Intergroup encounter rate and a measure of space-use sharing provided equally potent explanations for type sharing between social groups when closely related STs were taken into account, whereas animal age, sex and dispersal history had no influence. No antibiotic resistance was found, suggesting low rates of E. coli spillover from humans into this arboreal species.. We show that patterns of E. coli transmission reflect the social structure of this group-living lemur species. We discuss our results in the light of the species' ecology and propose scent-marking, a type of social contact not considered in previous epidemiological studies, as a likely route of transmission between groups. However, further studies are needed to explicitly test this hypothesis and to further elucidate the relative roles of direct contact and environmental transmission in pathogen transfer.

Topics: Animals; Drug Resistance, Bacterial; Ecosystem; Escherichia coli; Escherichia coli Infections; Feces; Female; Humans; Madagascar; Male; Multilocus Sequence Typing; Social Behavior; Strepsirhini; Zoonoses

Leptospirosis is a bacterial zoonosis of major concern on tropical islands. Human populations on western Indian Ocean islands are strongly affected by the disease although each archipelago shows contrasting epidemiology. For instance, Mayotte, part of the Comoros Archipelago, differs from the other neighbouring islands by a high diversity of Leptospira species infecting humans that includes Leptospira mayottensis, a species thought to be unique to this island. Using bacterial culture, molecular detection and typing, the present study explored the wild and domestic local mammalian fauna for renal carriage of leptospires and addressed the genetic relationships of the infecting strains with local isolates obtained from acute human cases and with Leptospira strains hosted by mammal species endemic to nearby Madagascar. Tenrec (Tenrec ecaudatus, Family Tenrecidae), a terrestrial mammal introduced from Madagascar, is identified as a reservoir of L. mayottensis. All isolated L. mayottensis sequence types form a monophyletic clade that includes Leptospira strains infecting humans and tenrecs on Mayotte, as well as two other Malagasy endemic tenrecid species of the genus Microgale. The lower diversity of L. mayottensis in tenrecs from Mayotte, compared to that occurring in Madagascar, suggests that L. mayottensis has indeed a Malagasy origin. This study also showed that introduced rats (Rattus rattus) and dogs are probably the main reservoirs of Leptospira borgpetersenii and Leptospira kirschneri, both bacteria being prevalent in local clinical cases. Data emphasize the epidemiological link between the two neighbouring islands and the role of introduced small mammals in shaping the local epidemiology of leptospirosis.

Topics: Animals; Comoros; Disease Reservoirs; DNA, Bacterial; Eulipotyphla; Genotype; Humans; Introduced Species; Leptospira; Leptospirosis; Madagascar; Phylogeny; Zoonoses

Cryptosporidium spp. is the most important parasitic diarrheal agent in the world, is among the top four causes of moderate-to-severe diarrheal disease in young children in developing nations, and is problematic as an opportunistic co-infection with HIV. In addition, Cryptosporidium is a persistent challenge for livestock production. Despite its zoonotic potential, few studies have examined the ecology and epidemiology of this pathogen in rural systems characterized by high rates of overlap among humans, domesticated animals, and wildlife. To improve our understanding of the zoonotic potential of Cryptosporidium species in the rural tropics, we screened humans, livestock, peridomestic rodents, and wildlife using PCR-RFLP and sequencing-based approaches to distinguish species of Cryptosporidium in rural southeastern Madagascar. Cryptosporidium of multiple species/genotypes were apparent in this study system. Interestingly, C. suis was the dominant species of Cryptosporidium in the region, infecting humans (n=1), cattle (n=18), pigs (n=3), and rodents (n=1). The broad species range of C. suis and the lack of common cattle Cryptosporidium species (Cryptosporidium parvum and Cryptosporidium andersoni) in this system are unique. This report represents the fifth confirmed case of C. suis infection in humans, and the first case in Africa. Few rural human and livestock populations have been screened for Cryptosporidium using genus-specific genotyping methods. Consequently, C. suis may be more widespread in human and cattle populations than previously believed.

Topics: Africa; Animals; Animals, Wild; Cattle; Cattle Diseases; Child; Coinfection; Cryptosporidiosis; Cryptosporidium; Dogs; Genotype; Humans; Lemur; Livestock; Madagascar; Male; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Rodent Diseases; Rodentia; Rural Population; Swine; Swine Diseases; Zoonoses

Surveillance of animal diseases in developing countries faces many constraints. Innovative tools and methods to enhance surveillance in remote and neglected areas should be defined, assessed and applied in close connection with local farmers, national stakeholders and international agencies. The authors performed a narrative synthesis of their own publications about surveillance in Madagascar and Cambodia. They analysed the data in light of their fieldwork experiences in the two countries' very challenging environments. The burden of animal and zoonotic diseases (e.g. avian influenza, African swine fever, Newcastle disease, Rift Valley fever) is huge in both countries which are among the poorest in the world. Being poor countries implies a lack of human and financial means to ensure effective surveillance of emerging and endemic diseases. Several recent projects have shown that new approaches can be proposed and tested in the field. Several advanced participatory approaches are promising and could be part of an innovative method for improving the dialogue among different actors in a surveillance system. Thus, participatory modelling, developed for natural resources management involving local stakeholders, could be applied to health management, including surveillance. Data transmission could benefit from the large mobile-phone coverage in these countries. Ecological studies and advances in the field of livestock surveillance should guide methods for enhancing wildlife monitoring and surveillance. Under the umbrella of the One Health paradigm, and in the framework of a risk-based surveillance concept, a combination of participatory methods and modern technologies could help to overcome the constraints present in low-income countries. These unconventional approaches should be merged in order to optimise surveillance of emerging and endemic diseases in challenging environments.

Topics: Animal Diseases; Animals; Animals, Domestic; Cambodia; Developing Countries; Ecology; Humans; Madagascar; Population Surveillance; Poverty; Zoonoses

Leptospirosis is a widespread but underreported cause of morbidity and mortality. It has rarely been reported in either humans or animals in Madagascar.. We conducted a cross-sectional survey of the inhabitants in Moramanga, Madagascar, in June 2011, to estimate the prevalence of human infection using the microscopic agglutination test (MAT). This activity was carried out as part of a workshop implemented by the Pasteur Institute of Madagascar, focusing on surveillance with a one week field study and targeting the health staff of the district level.. In total, we sampled 678 inhabitants from 263 households. The sex ratio (M/F) was 0.65 and the mean age 26.7 years. We obtained a value of 2.9% for the first recorded seroprevalence of this disease in the human community of Moramanga. Questionnaire responses revealed frequent contacts between humans and rodents in Moramanga. However, activities involving cattle were identified as a risk factor significantly associated with seropositivity (OR=3).. Leptospirosis remains a neglected disease in Madagascar. This study highlights the need to quantify the public health impact of this neglected disease in a more large scale, in all the country and to establish point-of-care laboratories in remote areas.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Agglutination Tests; Animals; Animals, Domestic; Antibodies, Bacterial; Cattle; Cattle Diseases; Child; Child, Preschool; Cross-Sectional Studies; Disease Reservoirs; Female; Housing; Humans; Immunologic Surveillance; Infant; Leptospira; Leptospirosis; Madagascar; Male; Middle Aged; Poverty; Prevalence; Rats; Rodent Diseases; Sampling Studies; Suburban Health; Surveys and Questionnaires; Young Adult; Zoonoses

In this cross-sectional seroepidemiological study we sought to examine the evidence for circulation of Rift Valley fever virus (RVFV) among herders in Madagascar and Kenya. From July 2010 to June 2012, we enrolled 459 herders and 98 controls (without ruminant exposures) and studied their sera (immunoglobulin G [IgG] and IgM through enzyme-linked immunosorbent assay [ELISA] and plaque reduction neutralization test [PRNT] assays) for evidence of previous RVFV infection. Overall, 59 (12.9%) of 459 herders and 7 (7.1%) of the 98 controls were positive by the IgG ELISA assay. Of the 59 ELISA-positive herders, 23 (38.9%) were confirmed by the PRNT assay (21 from eastern Kenya). Two of the 21 PRNT-positive study subjects also had elevated IgM antibodies against RVFV suggesting recent infection. Multivariate modeling in this study revealed that being seminomadic (odds ratio [OR] = 6.4, 95% confidence interval [CI] = 2.1-15.4) was most strongly associated with antibodies against RVFV. Although we cannot know when these infections occurred, it seems likely that some interepidemic RVFV infections are occurring among herders. As there are disincentives regarding reporting RVFV outbreaks in livestock or wildlife, it may be prudent to conduct periodic, limited, active seroepidemiological surveillance for RVFV infections in herders, especially in eastern Kenya.

Topics: Adolescent; Adult; Animals; Antibodies, Viral; Enzyme-Linked Immunosorbent Assay; Epidemics; Female; Humans; Immunoglobulin M; Kenya; Madagascar; Male; Middle Aged; Neutralization Tests; Rift Valley Fever; Rift Valley fever virus; Risk Factors; Ruminants; Young Adult; Zoonoses

In 2008-2009 a Rift Valley Fever (RVF) outbreak occurred in the Anjozorobe area, a temperate and mountainous area of the Madagascar highlands. The results of a serosurvey conducted in 2009 suggested recurrent circulation of RVF virus (RVFV) in this area and potential involvement of the cattle trade in RVFV circulation. The objective of this study was to describe the cattle trade network of the area and analyse the link between network structure and RVFV circulation. Five hundred and sixteen animals that tested negative in 2009 were sampled again in 2010. The 2009-2010 cattle-level seroconversion rate was estimated at 7% (95% CI: 5-10%). Trade data from 386 breeders of 48 villages were collected and analysed using social network analysis methodology, nodes being villages and ties being any movements of cattle connecting villages. The specific practice of cattle barter, known as kapsile, that involves frequent contacts between cattle of two breeders, was observed in addition to usual trade. Trade data were analysed using a logistic model, the occurrence of seroconversion at the village level being the outcome variable and the network centrality measures being the predictors. A negative association was observed between the occurrence of seroconversion in the village and introduction of cattle by trade (p=0.03), as well as the distance to the nearest water point (p=0.002). Conversely, the practice of kapsile, was a seroconversion risk factor (p=0.007). The kapsile practice may be the support for inter-village RVFV circulation whereas the trade network is probably rather implicated in the introduction of RVFV to the area from other parts of Madagascar. The negative association of the distance to the nearest water point suggests that after RVFV introduction, a substantial part of transmission may be due to vectors.

Topics: Animals; Antibodies, Viral; Cattle; Cattle Diseases; Madagascar; Rift Valley Fever; Rift Valley fever virus; Seroepidemiologic Studies; Zoonoses

The authors describe clinical and epidemiologic characteristics of severe presentations of Rift valley fever (RVF) during the 2008 epidemic in Madagascar.. The diagnosis was confirmed by RVF virus polymerase chain reaction (PCR), or detection of specifics antibodies by Elisa.. Sixteen cases of severe RVF were recorded. The sex-ratio was 7/1 and median age was 32 years (20/59 years). The risk factors of infection were: contact with infected animals or their meat (n=8), and travelling to a risk area (n=2). Hemorrhagic, neurological, and ocular manifestations were observed respectively in 87.5%, 43.8% and 6.3% of cases. All patients who died (n=4) presented with a hemorrhagic form of the disease.. The hemorrhagic form was the most frequent presentation of RVF and was responsible for a high level of mortality. Epidemiologic surveillance must be implemented.

Topics: Adult; Animal Husbandry; Animals; Antibodies, Viral; Cattle; Cattle Diseases; Disease Outbreaks; Female; Food Contamination; Hemorrhage; Humans; Insect Vectors; Madagascar; Male; Meat; Meningoencephalitis; Middle Aged; Occupational Diseases; Population Surveillance; Retinitis; Rift Valley Fever; Rift Valley fever virus; Risk Factors; RNA, Viral; Travel; Young Adult; Zoonoses

The Duffy blood group antigen is the portal of entry of the Plasmodiumvivax malaria parasite into human red blood cells and the receptor for a number of CXC and CC chemokines. We review here epidemiological data and evidence derived from therapeutic or experimental human infections associating P. vivax and the Duffy glycoprotein and laboratory studies indicating that P. vivax uses the Duffy antigen as a receptor to invade the red cell. We then review recent field observations indicating that the conclusion of the absolute dependence on the presence of Duffy on the red cell for P. vivax infection and development into the red cell no longer holds true and that in some parts of the world, P. vivax infects and causes disease in Duffy-negative people.

Topics: Africa; Animals; Antimalarials; Blood Group Antigens; Duffy Blood-Group System; Erythrocytes; Gene Deletion; Gene Expression Regulation; Humans; Madagascar; Malaria, Vivax; Papua New Guinea; Phenotype; Plasmodium vivax; Severity of Illness Index; Zoonoses

Topics: Animals; Biodiversity; Commerce; Conservation of Natural Resources; Extinction, Biological; Forestry; Humans; Lemur; Madagascar; Meat; Population Density; Trees; Zoonoses

Tuberculosis is highly prevalent in cattle in Madagascar. An epidemiological study based on genotyping of Mycobacterium bovis and its transmission to humans was carried out. The restriction fragment length polymorphism (IS6110 and DR markers) and spoligotyping were used to assess the genetic diversity of strains from different regions of Madagascar. One of these strains was isolated from goat, the other strains were isolated from zebu cattle. Nine IS6110 profiles, 20 DR profiles and 12 spoligotypes were obtained. About 90% of all isolates gave a single IS6110 band at about 1.8 kb. Most strains had the same spoligotype. M. bovis strains commonly lack spacers 39-43, and all Malagasy strains also lacked spacers 3-5, 8-10 and 16. This pattern has not been reported elsewhere. DR was the most discriminatory of the three markers. The patterns obtained with the three markers were combined to identify 34 different genotypes, one of which was found in 35% of the strains. No region-specific M. bovis genotype was identified, but the genotyping of 18 M. bovis strains isolated from patients showed that the human and bovine strains were identical, suggesting possible human contamination from zebu cattle.

Topics: Animals; Cattle; Deoxyribonucleases, Type II Site-Specific; DNA, Intergenic; Epidemiologic Methods; Genetic Variation; Genotype; Goats; Humans; Madagascar; Mycobacterium bovis; Polymorphism, Restriction Fragment Length; Tuberculosis; Tuberculosis, Bovine; Zoonoses

A polymerase chain reaction (PCR) technique was used for detection of the Leptospira interrogans rrs gene in kidney tissue from 115 rats, 50 zebu cattles and 13 pigs in an attempt to identify a possible animal reservoir of leptospirosis in Madagascar. In addition, serological testing of 105 individuals in close contact with animals was carried out. The PCR analysis was negative for all the samples tested and only one person was found seropositive at a low titer. The findings suggest that leptospirosis, if prevalent in Madagascar, is likely rare.

Topics: Animals; Bacteriological Techniques; Cattle; Cattle Diseases; Disease Reservoirs; Disease Vectors; DNA, Bacterial; Humans; Leptospira interrogans; Leptospirosis; Madagascar; Polymerase Chain Reaction; Population Surveillance; Prevalence; Rats; Rodent Diseases; Sensitivity and Specificity; Swine; Swine Diseases; Zoonoses

Four Gumboro disease (IBD) outbreaks were identified between February and June 1993 in the Antananarivo area (Madagascar) exhibiting the largest commercial poultry production activity. Affected birds were 3 to 5 weeks old, the mortality rate ranged from 5.70 to 27.4%. Typical symptoms and gross lesions were observed, necrotic degeneration of bursal follicles was also detected. By means of agar-immunodiffusion test, IBD viral antigen was demonstrated. Since the IBD has never been recorded in the country before, the probability of an external origin through the importation of day-old chicks is high.

Topics: Animals; Birnaviridae Infections; Chickens; Female; Humans; Infectious bursal disease virus; Madagascar; Male; Poultry Diseases; Zoonoses

Topics: Animals; Bacterial Infections; Humans; Madagascar; Protozoan Infections; Rickettsia Infections; Virus Diseases; Zoonoses

Topics: Animals; Antibodies, Viral; Arbovirus Infections; Arboviruses; Arthropod Vectors; Dengue; Hemagglutination Inhibition Tests; Humans; Madagascar; Yellow Fever; Zoonoses

Topics: Agglutination Tests; Animals; Antibodies, Bacterial; Humans; Leptospira; Leptospirosis; Madagascar; Rodentia; Species Specificity; Zoonoses

Topics: Animals; Anthrax; Cattle; Cattle Diseases; Clostridium; Disease Outbreaks; Madagascar; Zoonoses