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At least 19 recordsLinked to original sources
PubMed1997

[Natural history of chromoblastomycosis in Madagascar and the Indian Ocean] [Natural history of chromoblastomycosis in Madagascar and the [Natural history of chromoblastomycosis in Madagascar and the Indian Ocean].

The natural history of chromoblastomycosis was studied in Madagascar by analysing the characteristics of 1323 confirmed cases observed since 1955, including 45 patients receiving a new antifungic drug (terbinafine) during a multicentric study organized in 1995. The surveys data, conserved by the histopathology laboratory in the Institut Pasteur of Madagascar during 40 years, permit this retrospective analysis. The description of two ecosystems, one in the North with Fonsecaea pedrosoi evolving in the tropical rainforest and one in the South with Cladophialophora carrionii (41% of the whole sample) isolated in the spiny desert, demonstrates that the deforestation, in order to product charcoal and to build houses, is the primary factor associated with this disease. The epidemiologic (87% of patients are male and 96% are more than 16 years old, with more than 74% of the lesions located on feet and legs), mycologic (62% of the isolated strains belong to the F. pedrosoi species) and therapeutic (low efficiency of thiabendazole in long-term lesions, high efficiency of terbinafine especially on recent lesions and on Cladophialophora-infected patients) aspects of the natural history of chromomycosis confirmed that Madagascar is the most important focus in the world (global prevalence of about 1 for 8500 inhabitants), with few sporadic cases in the other islands of the Indian Ocean (La Reunion, Comoro islands and Mayotte). In the difficult context of Madagascar, the need for a non-specialized laboratory-applicable diagnostic technique that provides infection and species identification led the Institut Pasteur de Madagascar to develop an ELISA-based technique. A large-scale control throughout the country, with the assessment of effective oral chemotherapy with terbinafine, is seen as possible by the authors with the help of the manufacturer.

Antifungal Agents↗
PubMed1998

[Cancer in Madagascar. Experience of the Institut Pasteur de Madagascar from September 1992 to June 1996].

The Unit of the anatomo-pathology in the "Institut Pasteur de Madagascar" (IPM) examined in the period from September 1992 to June 1996 tissue specimens from 10,275 patients. Tumorous pathology presented 40% of the tissues and half of which were of malign etiology. 64% of the cancer diagnosed were in females. Cervical cancer was most frequently observed (17%), followed by breast cancer (16%). Cancer in the gastro-intestinal tract (15%) was most often located in the colon without sex difference. Stomach cancer occurring predominantly in males presented 25% of the total cases of cancer in the gastro-intestinal tract. Cancer of liver is rarely diagnosed despite the high prevalence of infection with hepatitis B virus. Skin cancer constituted 9% of the malign diagnosis and was mainly found in males. Children under 15 years old presented 7.4% of the total cases of malignancy with the haematopoietic tissues (30%) and the eyes (17%) as the most frequent topic locations. Due to a very low seroprevalence of the HIV in Madagascar, malign tumours associated to AIDS were only seen in a few rare cases. The review of cancer cases in the IPM may not be representative for the cancer epidemiology of Madagascar because of a general very low level of health care coverage, especially in the rural areas. Furthermore, a major part of the specimens originates from easily accessible organsystems, whereas other organs seem less investigated due to lack of appropriate available technique. Therefore, it is not feasible for the moment to establish a cancer register in Madagascar, although the Unit of Pathology in the IPM can offer a valid cancer diagnostical service.

Adolescent↗
PubMed2003

Seasonal changes in general activity, body mass and reproduction of two small nocturnal primates: a comparison of the golden brown mouse lemur ( Microcebus ravelobensis) in Northwestern Madagascar and the brown mouse lemur ( Microcebus rufus) in Eastern Madagascar.

To investigate for the first time the relationship between contrasting patterns of seasonal changes of the environment and activity, body mass and reproduction for small nocturnal primates in nature, we compared a population of golden brown mouse lemur ( Microcebus ravelobensis) in a dry deciduous forest of northwestern Madagascar and of the brown mouse lemur ( Microcebus rufus) in an evergreen rain forest of eastern Madagascar. Both species live under similar photoperiodic conditions. Golden brown mouse lemurs (GBML) were active during the whole period (May to December) irrespective of changing environmental conditions. In contrast, a part of the population of brown mouse lemurs (BML) showed prolonged seasonal torpor, related to body mass during periods of short day length and low ambient temperatures. Differences between species might be due to differences in ambient temperature and food supply. Body weight and tail thickness (adipose tissue reserve) did not show prominent differences between short and long photoperiods in GBML, whereas both differ significantly in BML, suggesting species-specific differences in the photoperiodically driven control of metabolism. Both species showed a seasonal reproduction. The rate of growth and size of the testes were similar and preceded estrous onset in both species suggesting a photoperiodic control of reproduction in males. The estrous onset in females occurred earlier in GBML than in BML. Estrous females were observed over at least 4 months in the former, but in only 1 month in the latter species. Intraspecific variation of estrous onset in GBML may be explained by body mass. Interspecific variation of female reproduction indicates species-specific differences in the control of reproduction. Thus, environmentally related differences in annual rhythms between closely related small nocturnal lemurs emerged that allow them to cope with contrasting patterns of seasonal changes in their habitats.

Animals↗
PubMed2006

Reconciling the origins of Africa, India and Madagascar with vertebrate dispersal scenarios.

Africa, India and Madagascar were once part of the supercontinent of Gondwana. This land mass began to fragment approx. 170 million years ago, and by 83 million years, all of the major components we recognize today were separated by tracts of water. Madagascar's fossil record and estimates of the timing of the extant vertebrate radiations in Madagascar are not easily reconciled with this history of fragmentation. Fossil faunas that lived prior to approx. 65 million years had a cosmopolitan flavour, but this was lost after the Cretaceous-Tertiary boundary. Phylogenetic reconstructions of most extant Malagasy vertebrate radiations indicate divergence times that postdate the End-Cretaceous (lemurs, tenrecs, cichlid fish) and even the Early Miocene (chameleons, carnivores, rodents). Most biogeographic explanations of these groups rely, therefore, on Simpson's model of sweepstakes dispersal (see also cover figure), but there are significant problems in applying the model to migrations from Africa to Madagascar, although its application is not so intractable between India and Madagascar. Alternative migration routes for consideration lie: (1) along the suite of fracture zones between Antarctica and Africa/Madagascar (known as the Antarctic-Africa Corridor), which may have been exposed episodically above sea level; (2) along a series of submerged basaltic ridges/plateaus with known or suspected continental crust between Antarctica and Africa/Madagascar/India flanking the Antarctic-Africa Corridor (e.g. the Madagascar Ridge, Mozambique Ridge, Conrad Plateau, Gunnerus Ridge); (3) between Africa and Madagascar along the Davie Ridge (parts of which are known to have been exposed episodically above sea level); (4) along the Deccan hotspot corridor between India and greater Africa.

Africa↗
PubMed2005

A study of spoligotyping-defined Mycobacterium tuberculosis clades in relation to the origin of peopling and the demographic history in Madagascar.

Despite well-developed tuberculosis (TB) control policies in Madagascar, the incidence of TB remains high and is estimated at about 100 new cases per 100000 inhabitants. This paper describes genetic characteristics of TB bacilli in Madagascar. Using an international spoligotyping database, SpolDB4, we also attempted to identify the origin of strains circulating in Madagascar. DNA polymorphism of 333 Mycobacterium tuberculosis complex isolates was assessed. A total of 301 isolates belonging to 60 spoligotyping-defined clusters were found, whereas 32 isolates harbored orphan patterns. By comparison with the international database, we identified a new genetic group of closely genetically related M. tuberculosis strains which we suggested to be specific from Madagascar. Most of them belonging to the East-African-Indian (EAI) superfamily of strains that are responsible for 14% of total TB cases (shared types ST1514-1525). These strains are closely related to the most prevalent shared type ST109, whose distribution is mainly confined to Madagascar. The observed distribution of genotypes shows that principal genetic group 1 strains (EAI, Beijing, CAS, Afri, "Manu") is high (35.4%) suggesting an ancient evolutionary history of tuberculosis in Madagascar, in relation to the origin of peopling and the demographic history.

Bacterial Typing Techniques↗
PubMed2002

Influenza outbreak--Madagascar, July-August 2002.

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.

Disease Outbreaks↗
PubMed2006

Population structure of the malaria vector Anopheles funestus (Diptera: Culicidae) in Madagascar and Comoros.

Microsatellites were used as markers for a study of the population structure of Anopheles funestus on Madagascar and Comoros. Mosquitoes were collected in four different localities on Madagascar and one on Comoros. There was a significant genetic differentiation between all samples from Madagascar and that from Comoros (P<0.05). With respect to the Madagascar mosquito samples, it was found that there were no significant genetic differences between samples that were collected at the east coast, and in the highlands, respectively. By contrast, the west coast sample exhibited significant genetic differences (with regard to all Madagascar samples). The results are discussed with respect to population distribution and migration of A. funestus from mainland Africa and the islands east of the mainland.

Animals↗
PubMed2006

Deforestation and plant diversity of Madagascar's littoral forests.

Few studies have attempted to quantify the reduction or document the floristic composition of forests in Madagascar. Thus, we focused specifically on deforestation and plant diversity in Madagascar's eastern littoral community. We used a data set of approximately 13,500 specimen records compiled from both historical and contemporary collections resulting from recent intensive inventory efforts to enumerate total plant species richness and to analyze the degree of endemism within littoral forests. Change in littoral forest cover from original to current extent was estimated using geographical information systems tools, remote sensing data (satellite imagery and low-elevation digital photography), and environmental data layers. Of the original littoral forest only 10.3% remains in the form of small forest parcels, and only 1.5% of these remaining fragments are included within the existing protected-areas network. Additionally, approximately 13% of Madagascar's total native flora has been recorded from these forests that originally occupied <1% of its total land surface, and over 25% of the 1535 plant species known from littoral forests are endemic to this community. Given the ongoing pressure from human settlement along Madagascar's eastern coast, protection of the remaining forest fragments is critical for their survival. Fifteen of the largest intact littoral forest fragments we identified, collectively representing 41.5% of remaining littoral forest, are among priority sites recommended to the government of Madagascar for plant conservation and incorporation into the protected-areas network.

Biodiversity↗
PubMed2006

Historical biogeography of the strepsirhine primates of Madagascar.

Lying some 400 km off the coast of southeastern Africa, Madagascar is the world's largest oceanic island. It has been in roughly the same position relative to its parent continent for 120 million years, and as a consequence its mammal fauna is unusual in composition, with a low number of major taxa but a high diversity at lower taxonomic levels. Among Madagascar's native terrestrial mammals, only the orders Primates, Rodentia, Carnivora and Insectivora are represented (plus, until recently, the enigmatic and endemic Bibymalagasia, and Artiodactyla in the form of semiaquatic pygmy hippopotamuses). This reflects the fact that terrestrial mammals are notoriously poor over-water dispersers; yet at the same time the ancestors of all of Madagascar's mammals had to have crossed a wide oceanic barrier to get to the island at various points during the Tertiary. Here I examine the palaeogeographic evidence for potential land bridge or 'stepping-stone' connections with adjacent continents from the Mesozoic through the Cenozoic, and review the fossil records and phylogenies of each of Madagascar's mammalian groups in an attempt to estimate the minimum number of crossings necessary to produce the island's current faunal composition. Probable monophyletic origins for each major group, and thus a smaller rather than a larger number of crossings of the Mozambique Channel, imply that this water barrier has acted as a powerful filter; so powerful that it is unclear whether any crossings would have been possible without some form of subaerial connection, however ephemeral, at least from time to time during the Tertiary. Clarification of how Madagascar's terrestrial mammal fauna may have originated is thus as likely to emerge from the geology of the seafloor surrounding the island as it is to come from the fossil record or from the internal and external relationships of its various components.

Animal Migration↗
PubMed2003

Plants traditionally prescribed to treat tazo (malaria) in the eastern region of Madagascar.

BACKGROUND: Malaria is known as tazo or tazomoka in local terminology in Madagascar. Within the context of traditional practice, malaria (and/or malaria symptoms) is commonly treated by decoctions or infusions from bitter plants. One possible approach to the identification of new antimalarial drug candidates is to search for compounds that cure or prevent malaria in plants empirically used to treat malaria. Thus, it is worth documenting the ethnobotanical data, and testing the antiplasmodial activity of the extractive from plants. METHODS: We interviewed traditional healers, known locally as ombiasy, at Andasibe in the eastern, rainy part of Madagascar. We recorded details of the preparation and use of plants for medicinal purposes. We extracted five alkaloids from Z. tsihanimposa stem bark, and tested them in vitro against Plasmodium falciparum FCM29. RESULTS: We found that traditional healers treat malaria with herbal remedies consisting of one to eight different plants. We identified and listed the medicinal plants commonly used to treat malaria. The plants used included a large number of species from different families. Zanthoxylum sp (Rutaceae) was frequently cited, and plants from this genus are also used to treat malaria in other parts of Madagascar. From the plant list, Zanthoxylum tsihanimposa, bitter plant endemic to Madagascar, was selected and examined. Five alkaloids were isolates from the stem bark of this plant, and tested in vitro against malaria parasite. The geometric mean IC50 values ranged from 98.4 to 332.1 micromolar. The quinoline alkaloid gamma-fagarine exhibited the strongest antiplasmodial activity. CONCLUSIONS: The current use of plants for medicinal purposes reflects the attachment of the Malagasy people to their culture, and also a lack of access to modern medicine. The possible extrapolation of these in vitro findings, obtained with plant extracts, to the treatment of malaria and/or the signs evoking malaria is still unclear. If plants are to be used as sources of novel antimalarial compounds, we need to increase our knowledge of their empirical use to improve plant selection. In the hope of preserving useful resources, we should now gather and record ethnobotanical data in Madagascar, and should try to bridge the gaps between empirics and realism.

Animals↗
PubMed1999

[Anopheles mascarensis (De Meillon, 1947): main vector of malaria in the region of Fort-Dauphin (south-east of Madagascar)].

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.

Animals↗