Larval Environmental Temperature and Insecticide Exposure Alter Aedes aegypti Competence for Arboviruses

Autor(es): Muturi, Ephantus J.; Alto, Barry W.


Resumo: Temperature is a key factor influencing mosquito growth and development and is also known to affect insecticide efficacy. We evaluated the effects of larval rearing temperature and exposure to insecticides on adult mosquito fitness and competence for arboviral infection using Sindbis virus (SINV). We exposed newly hatched larvae of Aedes aegypti to an environmentally realistic level of insecticide malathion at 20 degrees C and 30 degrees C and allowed the resulting adults to feed on SINV-infected blood meal. Exposure to malathion significantly reduced survival to adulthood. Statistically significant interactions between temperature and malathion were observed for body size, estimated population growth, and SINV infection and dissemination. Malathion-exposed Ae. aegypti cohorts had significantly higher population growth at 20 degrees C than at 30 degrees C. Body size decreased with higher temperature and malathion-exposed females were larger than unexposed females at 20 degrees C but not at 30 degrees C. Viral infection and dissemination increased with larval rearing temperature and were higher in malathion-exposed than unexposed females at 30 degrees C but not at 20 degrees C. These results show that environmental factors, including those factors used in controlling mosquitoes, experienced by immature stages have latent effects that continue to adulthood and alter vector competence to arboviruses.


Palavras-Chave: Aedes; Arbovirus(es); Mosquito(es); Vector; Vector-borne


Imprenta: Vector-Borne and Zoonotic Diseases, v. 11, n. 8, p. 1157-1163, 2011


Identificador do objeto digital: 10.1089/vbz.2010.0209


Descritores: Aedes aegypti - Public health


Data de publicação: 2011