Insecticide Susceptibility of Aedes aegypti in Different Parts of Thailand

Abstract Larvae of Aedes aegypti, the main vector of dengue hemorrhagic fever, were collected from different parts of Thailand determined to be high risk areas by average annual cases. The larvae and adults were tested in the laboratory based on the standard WHO test, using discriminating concentrations to determine their susceptibility to insecticides used for dengue control, ie temephos, permethrin, deltamethrin, cyfluthrin, and fenitrothion. The results showed permethrin resistance in all studied area. Susceptibility to the other insecticides varied in each studied area, from susceptible to tolerant, to resistant. The results suggested that insecticides used for control of Ae. aegypti cannot be used nationwide; but depends on mosquito susceptibility in the specific area. Insecticide susceptibility should be determined for each area, to inform appropriate insecticide selection. Keywords : insecticde resistance; Aedes aegypti; susceptibility test