clove and Arbovirus-Infections

Some arboviruses are highly pathogenic for Men or animals. Arboviruses epidemiological patterns in Madagascar were determined by entomological, serological, and virological surveys. We listed potentials arboviruses vectors in Madagascar. Entomological results generated by us during five years, as well as prior to, are shown. We caught more than 150,000 hematophagous arthropods, belonging to 107 species at least. 3 of these species were new. 4183 inoculation pools were done. We studied serollogically (by HI test) samples collected from 563 animals and 626 Men. Our data, in agreement with others collected from 1965 to 1982, demonstrate that arboviruses circulate in the whole island. Positive reactions were obtained mainly with Flavivirus, in particular with West-Nile. Nine various arboviruses, including dengue-2 virus isolated from an individual having travelled to La Réunion, have been isolated. Dakar-Bat and Mengo virus have been observed. We studied transmission cycles of the following viruses: Babanki, West-Nile, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, MMP 158, Ngari, Perinet and Andasibe; the last 2 being endemics. In relation to Madagascar biogeographic characteristics (long-term isolation, scarce communications, high endemicity, and low vertebrate density), we evaluated the risk of potential introduction and amplification of various arboviruses (dengue, yellow fever, japanese encephalitis, Sindbis and Chikungunya). The risk is very high for dengue due to the presence of susceptible mosquitoes strains while the virus circulates in East Africa and in the Indian Ocean area. This risk seems to be very low for yellow fever, and intermediate for other arboviruses.

Topics: Animals; Arbovirus Infections; Arthropod Vectors; Culicidae; Humans; Insect Vectors; Madagascar; Risk Factors

The genus Coquilletidia includes some of the mosquitoes involved in the transmission of numerous arbovirosis. Adults are locally abundant and very aggressive for men. In Madagascar, thus genus concerns 3 species among which 2 are endemic and had not been described at larval stage this far. The authors describe a single larva of Coquilletidia collected at Ankazobe in the Middle West of Madagascar, at an altitude of 1200 meters. The geographical distribution of Coquilletidia adults collected in various bio-climatic zones in Madagascar, combined with observed morphological characters, permit us to attribute this larva to Cq. grandidieri.

Topics: Altitude; Animals; Arbovirus Infections; Climate; Culicidae; Endemic Diseases; Female; Insect Vectors; Larva; Madagascar; Male; Population Density

A study was made of 25 male and 43 female mosquitoes belonging to the Culex (Culex) univittatus group, from different localities in Madagascar, Indian Ocean. This showed that Culex neavei Theobald, 1906 is present on the island, at least in the Tsiroanomandidy region. As demonstrated previously, Cx. univitatus Theobald, 1901 is also present. Because of the presence of some atypical forms, firm identifications was made only in males according to the structure of the leaflet of the sub-apical lobe of the gonocoxite. The relevance of the presence of Cx. neavei to the epidemiology of West Nile and Babanki viruses in Madagascar is discussed.

Topics: Animals; Arbovirus Infections; Arboviruses; Culex; Female; Insect Vectors; Madagascar; Male

Some arboviruses are highly pathogenic for Men or animals, Arboviruses epidemiological patterns in Madagascar were determined by entomological, serological, and virological surveys. We listed potentials arboviruses vectors in Madagascar. Entomological results generated by us during five years, as well as prior to, are shown. We caught more than 150,000 hematophagous arthropods, belonging to 107 species at least. 3 of these species were new. 4183 inoculation pools were done. We studied serologically (by HI test) samples collected from 563 animals and 626 Men. Our data, in agreement with others collected from 1965 to 1982, demonstrate that arboviruses circulate in the whole island. Positive reactions were obtained mainly with Flavivirus, in particular with West-Nile. Nine various arboviruses, including dengue-2 virus isolated from an individual having travelled to La Réunion, have been isolated. Dakar-Bat and Mengo virus have been observed. We studied transmission cycles of the following viruses: Babanki, West-Nile, Rift Valley Fever, Crimean-Congo Hemorrhagic Fever, MMP 158, Ngari, Perinet and Andasibe; the last 2 being endemic. In relation to Madagascar biogeographic characteristics (long-term isolation, scarce communications, high endemicity, and low vertebrate density), we evaluated the risk of potential introduction and amplification of various arboviruses (dengue, yellow fever, japanese encephalitis, Sindbis and Chikungunya). The risk is very high for dengue due to the presence of susceptible mosquitoes strains while the virus circulates in East Africa and in the Indian Ocean area. This risk seems to be very low for yellow fever, and intermediate for other arboviruses.

Topics: Animals; Arbovirus Infections; Arboviruses; Arthropod Vectors; Humans; Insect Vectors; Madagascar; Risk

Since 1977, the Pasteur Institute of Madagascar has been studying, during six surveys, the arboviruses of Nosy-Be area, in the north-west of Madagascar. 47.2% out of 271 human sera and 11.3% out of 151 sera of Lemurs, tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. The results show an important prevalence of Flaviviruses. West Nile and Dengue 1 viruses were probably circulating some years before the surveys. Antibodies against Sindbis and Rift Valley Fever viruses, were found only in few subjects. Bunyamwera and California groups of virus are absent. The rate of positive Lemurs is weak, particularly in Lemur macaco macaco. Flaviviruses are the most frequent. 12,262 haematophagous diptera (11,965 Culicidae belonging to 40 species) were caught. Aedes aegypti and Aedes albopictus are both present. Arbovirus isolation attempts from 394 mosquito pools failed; only Mengo virus was isolated from four pools of Eretmapodites quinquevittatus and one pool of Aedes (Skusea) sp.

Topics: Animals; Antibodies, Viral; Arbovirus Infections; Arboviruses; Culicidae; Diptera; Humans; Lemur; Madagascar

Topics: Animals; Antibodies, Viral; Arbovirus Infections; Arboviruses; Culex; Hemagglutination Inhibition Tests; Humans; Madagascar

Since 1977, the Pasteur Institute of madagascar has been studying, during six surveys, the arboviruses of Nosy-Be area, in the north-west of Madagascar. 47.2 p. 100 out of 271 human sera and 11.3 p. 100 out of 150 animal sera (mostly from Lemurs), tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. The results show an important prevalence of Flaviviruses. West-Nile and Dengue 1 viruses were probably circulating some years before the surveys. Antibodies against Sindbis and Rift Valley Fever viruses, were found only in few subjects. Bunyamwera and Tahyna viruses are absent. The rate of positive Lemurs is weak, particularly in Lemur macaco species. Flaviviruses are the most frequent. 12262 haematophagous diptera (11965 Culicidae belonging to 40 species) were caught . Aedes aegypti and Aedes albopictus are both present. Arbovirus isolation attempts from 394 mosquito pools failed; only Mengo virus was isolated from four pools of Erethmapodites quinquevittatus and one pool of Aedes (Skusea) sp.

Topics: Animals; Antibodies, Viral; Arbovirus Infections; Bunyaviridae; Diptera; Female; Humans; Insect Vectors; Madagascar; Male; Togaviridae

The epidemiological role played by lemurs in the circulation of arboviruses in Madagascar has been studied. From serological (HAI) tests, exposure of lemurs to alphaviruses and flaviviruses appears to vary considerably with location and species of lemur; positive tests varied from 0 to 32%. Finally, the data concerning the lemurophilic part of the mosquito fauna suggests that some lemur species and man are infected by the same arboviruses, especially West Nile virus. The susceptibility of these primates to yellow fever virus, which has not yet occurred in Madagascar is under study.

Topics: Animals; Antibodies, Viral; Arbovirus Infections; Arboviruses; Culicidae; Feeding Behavior; Lemur; Lemuridae; Madagascar

Topics: Academies and Institutes; Adult; Animals; Animals, Newborn; Antigens, Viral; Arbovirus Infections; Arboviruses; Disease Vectors; Humans; Lemur; Madagascar; Male; Mice

Topics: Academies and Institutes; Animals; Antigens, Viral; Arbovirus Infections; Arboviruses; Diagnosis, Differential; Hemagglutination Tests; Humans; Madagascar; Mice; Microbiological Techniques; Serologic Tests; Virulence

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