Associations of arbovirus vectors with gallery forests and domestic environments in southeastern Bolivia.

Abstract

Abstract : Populations of Aedes aegypti (Linnaeus), the vector of dengue and urban yellow fever (YF), have reinfested some urban areas of Bolivia (I-3). While both dengue and YF outbreaks can occur in Ae. aegypti-infested cities and villages, the probability of a YF outbreak is perhaps greater, because that virus is present in a forest cycle throughout much of Bolivia (1, 4). while dengue is not known to exist in a forest cycle in the New World. Nevertheless, plaque-reduction neutralization tests conducted on paired sera from cases of febrile illness in an isolated population of Ayoreo Indians in the Rincon del Tigre area of Bolivia have demonstrated seroconversion to dengue virus. These cases of suspected dengue fever occurred almost concurrently with cases of YF during the first quarter of 1981. The tests were conducted in early 1982 at the Waiter Reed Army institute of Research in Washington, D.C. The serologic results obtained aroused considerable interest, since reports from the Bolivian Ministry of Health indicated that there were no Ae. aegypti at Rincon del Tigre. Consequently. a trip was made to Rincon del Tigre in May-June 1982 to collect mosquitoes that could yield entomologic information and provide material for virus isolation efforts. The specific aims of this project were (1) to conduct a survey of Rincon del Tigre for Ae. aegypti populations; (2) to develop a representative taxonomic collection of mosquito species in the area; (3) to collect mosquitoes for use in virus isolation attempts; and (4) to characterize the mosquitoes associated with domestic and sylvatic environments. This article reports the results of systematic collection of mosquitoes in the peridomestic and sylvan environments. Results of the taxonomic studies have been reported separately.