Study of the vector competence of populations of Aedes (Stegomyia) albopictus (Skuse) (Diptera: culicidae) from São Paulo State (Brazil) for dengue and Venezuelan equine encephalitis viruses and the effect of the exposition to infection on the longevity

Author(s)

Zoraida Del Carmen Fernández Grillo

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Saúde Pública (FSP/CIR)
• Defense date: 2003-06-12

Examining board members

Oswaldo Paulo Forattini; Julia Maria Martins de Souza Felippe; Délsio Natal; Ricardo Lourenço de Oliveira; Maria Anice Mureb Sallum

• Advisor: Oswaldo Paulo Forattini

Abstract

Objectives. To evaluate the vector competence of Ae. albopictus populations from Vale do Paraíba (urban locality) and Vale do Ribeira (rural locality) for DENV-1 and DENV-2 and lC, ID and IF subtypes of VEEV and the effect of infection on mosquito longevity. Methods. Four to 6 days old females were orally infected with DENV-1 and DENV-2 and, IC, ID and IF subtypes of VEEV. Infection, dissemination and transmission rates of viruses were determined. Life tables were constructed for mosquitoes that were not exposed and exposed to virus infection. Results. The populations of Ae. albopictus shown low rates of infection for DENV-1 and DENV-2. Spite of the dissemination of those viruses, the transmission was not detected. The longevity of mosquito populations was not affected by the exposition to DENV infection. The infection rates for IC and ID of VEEV were high but lower for IF subtype. However, the titers of infection for the three subtypes were higher. The transmission for IC and ID subtypes was detected. The longevity of mosquitoes was reduced after the exposition to IC infection. Conclusions. The Ae. albopictus populations evaluated are susceptible for DENV infection and competent to transmit enzootic and epizootic subtypes of VEEV. Another studies must be done with IF subtype. The longevity could be affected by the infection with IC subtype of VEEV. (AU)