DENSIDADE POPULACIONAL DE Aedes aegypti (DIPTERA: CULICIDAE) E TAXA DE INFECÇÃO POR VÍRUS DENGUE EM SÃO LUÍS, MARANHÃO

Abstract

This study aimed to obtain Aedes aegypti density population and to identify the presence of dengue virus in adults vector collected at different periods of the year in São Luís, Maranhão. Mosquitoes were collected in three periods: dry (November and December 2008), rainy (March and April 2009) and intermediate (July and August 2009). Were visited 320 properties in eight neighborhoods previously drawn from two districts: Coréia de Baixo , Lira , Goiabal and João Paulo ( Distrito Centro ) and Itapiracó , Residential Canudos , Conjunto Cohatrac I and Vila Luisão ( Distrito COHAB ). We used mechanical vacuum on the battery to catch A. aegypti adults. After counting, identification and storage, the specimens were sent to the Instituto Evandro Chagas , in Ananindeua, State of Pará, to carry out the molecular and viral analysis for virus isolation and Reverse Transcription followed by Polymerase Chain Reaction (RTPCR). Also obtained climatological data for the period of study. We collected 563 mosquitoes A. aegypti, with predominance of adults in the rainy season, but not have significant difference in the amount of specimens of A. aegypti per period. There was also no positive and negative correlation between the factors and the number of A. aegypti adults. About the neighborhoods, João Paulo and Goiabal were obtained statistically significant densities. Specimens of A. aegypti were divided into pools, considering the neighborhoods of collection, with 13 formed in the dry season, 23 in the rainy season and 15 in the intermediate period. Viral isolation and RT-PCR of samples were not positive for the attested dengue virus. These results show that A. aegypti density increased during the rainy season and the João Paulo and Goiabal neighborhoods had the largest number of specimens, showing that in São Luís, the climatic factors may to influence the vector seasonal fluctuation.