Aedes egypti resistance to temephos during 2001 in several municipalities in the states of Rio de Janeiro, Sergipe, and Alagoas, Brazil
Ima Aparecida BragaI, II, III; José Bento Pereira LimaI, II; Sidinei da Silva SoaresIV; Denise ValleI, II,1
I Laboratório de Transmissores de Hematozoários, Departamento de Entomologia, Instituto Oswaldo Cruz-Fiocruz, Av. Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brasil
IIL aboratório de Entomologia, Instituto de Biologia do Exército, Rio de Janeiro, RJ, Brasil
III Secretaria de Vigilância em Saúde, Brasília, DF, Brasil
IV Fundação Nacional de Saúde, Rio de Janeiro, RJ, Brasil
or more than 30 years temephos, an organophosphate insecticide, has been the sole larvicide used in Brazil in the control of Aedes aegypti. Organophosphates were also used for adult control, being replaced by pyrethroids since l999. In this same year, the Brazilian Health Foundation started the coordination of the Ae. aegypti Insecticide Resistance Monitoring Program. In the context of this program, our group was responsible for the detection of temephos resistance in a total of 12 municipalities in the states of Rio de Janeiro (RJ), Alagoas (AL), and Sergipe (SE) during 2001. In each municipality, a pool of mosquitoes collected from different districts was used, with the exception of Rio de Janeiro city, where eight districts have been separately evaluated. Exposure of larvae to the diagnostic dose of temephos revealed resistance in all localities examined, with mortality levels ranging from 4% (Pilares district, Rio de Janeiro, RJ) to 61.9% (Campos dos Goytacazes, RJ). Quantification of mortality showed resistance ratios from 6.1 (Aracaju, SE) to 16.8 (São Gonçalo, RJ and Penha district, Rio de Janeiro, RJ). The national dengue control program is presently using these data to subside insecticide resistance management.