277 resultados para Guiana
Resumo:
The objectives of the present study were to broaden the survey of simuliid species in French Guiana and to cytologically analyze the species in the Simulium perflavum species group. Twelve species of Simulium were collected from which S. goeldii, S. quadrifidum, S. trombetense, S. near incrustatum, S. metallicum (s.l.) sp1, S. metallicum (s.l.) sp2 and S. ochraceum (s.l.) are reported for the first time for this region. The only species collected in the S. perflavum group was S. rorotaense; 34 larvae of this species were cytologically analyzed, all of which had the standard sequence. S. metallicum (s.l.), S. ochraceum (s.l.), S. guianense (s.l.) and S. oyapockense (s.l.) are involved with transmission of onchocerciasis in Central and South America, however, in French Guiana these species were not found biting humans during the sampling period. With the few collections made during this study, we increase the number of simulid species known in French Guiana from 6 to 13. It is clear that more simuliid species can be expected to be found when more sampling is done, including collections in other ecoregions in French Guiana.
Resumo:
A survey was carried out on 1487 individuals to assess the seroprevalence of Trypanosoma cruzi infection in French Guiana. The overall prevalence of T. cruzi specific IgG was 0.5%. In multivariate analysis, residence in areas where housing is favorable for the presence of triatomine bugs was the only factor associated with the presence of T. cruzi antibodies. These results have implications for public health since blood donors are not routinely screened for T. cruzi infection in French Guiana.
Resumo:
Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia) ininii Floch & Abonnenc, Lu.(Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time Lu. (Nys.) flaviscutellata was found harboring Leishmania (Viannia) guyanensis and Lu. (Tri) ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy.) squamiventris maripaensis harboring L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.
Resumo:
Panstrongylus mitarakaensis n. sp. is described from French Guiana. Morphological characters are provided. This small species, less robust than other Panstrongylus species, shows a pronotum shape similar to species of the "P. lignarius complex". However, others characters such as the postocular part of head, the obsolete tubercle on the anterior lobe of pronotum, and the lateral process on the antenniferous tubercle distinguish it from the species in that complex. The taxonomic key of the genus Panstrongylus is actualized.
Resumo:
French Guiana is one of the areas in South America most affected by malaria and where the disease has become a serious public health problem. In spite of this situation, little recent entomological data are available from the main localities where the disease occurs, even though they are crucial for development of an effective vector control strategy. A longitudinal entomological survey was carried out from March 2000-February 2002 in three Amerindian villages, namely Twenké, Taluène and Cayodé, located in the Amazonian forest of the Upper-Maroni area, to assess anopheline mosquitoes and malaria transmission dynamics. Anopheles darlingi (Diptera: Culicidae) was the most abundant mosquito species caught during the study. This efficient American malaria vector was active the entire year, but showed an evident peak of abundance during the main rainfall season, from April-June, with an average human biting rate of 255.5 bites per person per night. Parity rates were homogeneous all year, indicating no significant seasonal variability in female survival rates. Estimated vectorial capacity indices were higher during the rainy season, even though the risk of transmission was present throughout the year (VCI > 1). A total of 14 An. darlingi were found infected with Plasmodium falciparum, Plasmodium vivax or Plasmodium malariae. The annual circumsporozoite indices were 0.15, 0.14 and 0.05, and the entomological inoculation rates were 22.8, 27.4 and 14.4 infected bites per person per year in Twenké, Taluène and Cayodé, respectively. An. darlingiwas endo-exophagic and rather exophilic in these localities. The species was collected throughout the night but was more aggressive between 21:30-03:30 h and after 05:30 h. Parity rates were homogeneous during the entire night. Impregnated hammock and/or bed nets, coupled with the use of mosquito repellents, as well as the early treatment of malarial cases, appear to be the most suitable tools for fighting malaria in these Amerindian villages since the spraying of residual insecticides is inefficient because of vector biology and the housing structure.
Resumo:
An annotated list of the triatomine species present in French Guiana is given. It is based on field collections carried out between 1993-2008, museum collections and a literature review. Fourteen species, representing four tribes and six genera, are now known in this country and are illustrated (habitus). Three species are recorded from French Guiana for the first time: Cavernicola pilosa, Microtriatoma trinidadensis and Rhodnius paraensis. The two most common and widely distributed species are Panstrongylus geniculatus and Rhodnius pictipes. The presence of two species (Panstrongylus megistus and Triatoma maculata) could be fortuitous and requires confirmation. Also, the presence of Rhodnius prolixus is doubtful; while it was previously recorded in French Guiana, it was probably mistaken for R. robustus. A key for French Guiana's triatomine species is provided.
Resumo:
In French Guiana, pyrethroids and organophosphates have been used for many years against Aedes aegypti. We aimed to establish both the resistance level of Ae. aegypti and the ultra low volume spray efficacy to provide mosquito control services with practical information to implement vector control and resistance management. Resistance to deltamethrin and fenitrothion was observed. In addition, the profound loss of efficacy of AquaK'othrine® and the moderate loss of efficacy of Paluthion® 500 were recorded. Fenitrothion remained the most effective candidate for spatial application in French Guiana until its removal in December 2010. Further investigation of the mechanism of resistance to deltamethrin demonstrated the involvement of mixed-function oxidases and, to a lesser extent, of carboxylesterases. However, these observations alone cannot explain the level of insecticide resistance we observed during tube and cage tests.
Resumo:
Anopheles darlingi Root is the major vector of human malaria in the Neotropics and has been considered to be the sole malaria vector in French Guiana. The presence of other potential vectors suggests that malaria may be transmitted by other species under certain conditions. From 2006-2011, all anopheline specimens collected from 11 localities were assayed to determine if the Plasmodium circumsporozoite protein was present. In addition to An. darlingi, we found Anopheles oswaldoi, Anopheles intermedius and Anopheles nuneztovari specimens that were infected with Plasmodium sp. Further investigations on the behaviour and ecology of An. oswaldoi, An. intermedius and An. nuneztovari are necessary to determine their role in malaria transmission in French Guiana.
Resumo:
In a climate of growing concern that Plasmodium falciparum may be developing a drug resistance to artemisinin derivatives in the Guiana Shield, this review details our current knowledge of malaria and control strategy in one part of the Shield, French Guiana. Local epidemiology, test-treat-track strategy, the state of parasite drug resistance and vector control measures are summarised. Current issues in terms of mobile populations and legislative limitations are also discussed.
Resumo:
Três espécies novas de abelhas do gênero Lestrimelitta são descritas: L. danuncia sp. nov. (da Costa Rica e Panamá), L. mourei sp. nov. (da Costa Rica) e L. glaberrima sp. nov. (da Guiana Francesa). Todas essas espécies foram identificadas anteriormente como Lestrimelitta limao Smith.
Resumo:
In South America, the presence of the Leishmania RNA virus type 1 (LRV1) was described in Leishmania guyanensis and Leishmania braziliensis strains. The aim of this study was to determine the prevalence distribution of LRV1 in Leishmania isolates in French Guiana given that, in this French overseas department, most Leishmania infections are due to these parasite species. The presence of the virus was observed in 74% of Leishmania spp. isolates, with a highest presence in the internal areas of the country.
Resumo:
Julkaisussa: De wijd-beroemde voyagien na Oost en West-Indien. Vol I
Resumo:
Even though shark-cetacean interactions have been the subject of numerous studies worldwide, several ecological aspects such as competition, predation risk and co-evolution remain unclear. on February 16th, 2008, during a photo-identification survey to investigate population parameters of Guiana dolphins, Sotalia guianensis, in estuarine waters of Parana State (25[degree]S; 48[degree]W), Brazil, an adult dolphin was photographed without its dorsal fin. A detailed analysis of the healed area on the injured dolphin showed that the circular, crescent-shaped outlined wound was provoked by the bite of a bull shark, Carcharhinus leucas. Wound shape, prey-predator distributional patterns (sympatry) and feeding habits of the shark species here considered were indicative of the species' identity. The wound is likely to be the result of a failed predation attempt. Interactions between C. leucas and S. guianensis should be expected, since they are sympatric along almost all of their distribution range in the tropical and subtropical western South Atlantic. The presented observation adds S. guianensis to the list of cetacean species involved in interactions with large coastal predatory sharks.