Prevalence of Stegomyia albopicta in Dakshina Kannada district of Karnataka, India

Dengue is one of the rapidly spreading mosquito-borne diseases transmitted worldwide by the bites of infected Stegomyia aegypti and St. albopicta mosquito. Both species are adapted for human habitation and breeds mainly in temporary water bodies. In the present study, a preliminary larval survey was carriedout in four different localities of Dakshina Kannada District. Of the 1094 suspected water bodies, 496 sites showed the presence of St. albopicta larvae and none of them showed the presence of St. aegypti indicating the dominance of the former species. The occurrence of St. albopicta was significantly higher in natural phytotelmata compared to artificial containers. Among the different breeding sites, receptacles contributed 24.5% of larval positivity. The receptacles also showed a higher breeding preference ratio (1.56) indicating that abandoned waste thrashes when receives water may act as the most preferred breeding sites for dengue vector species.

Occurrence of immature forms of culicids (Insecta: Diptera) in the northeastern region of Brazil

The Culicidae family is represented by approximately 3,610 species, among which many are involved in transmission of pathogens and parasites, thus presenting great medical-veterinary importance. In Brazil, the state of Pernambuco is considered an endemic area for many diseases vectored by mosquitoes, such as human and canine filariasis, caused by Wuchereria bancrofti and Dirofilaria immitis, respectively. The aim of this study was to evaluate the occurrence of immature forms of culicids, over an one-year period, in a specific area of northeastern region of Brazil. Culicids larvae were collected from traps located on the ground and in treetops, between october 2012 and september 2013. Ten different species of culicids were identified. The greatest number of larvae were collected in september 2013 and the lowest number in december 2012. Stegomyia (Stegomyia) albopicta (46.45%; 5,908/12,718), Culex (Culex) maxi (35.56%; 4,523/12,718) and Limatus durhamii (12.58%; 1,600/12,718) were the most frequent species. The human and animal populations living in the study area are exposed to culicids and transmission agents throughout the year, especially after the rains. Therefore, control and prevention measures against culicids must be adopted in the study area.