Susceptibility of the Dengue Vector Aedes aegypti to Various Insecticides in Lahore, Pakistan

Objective: Present studies were carried out to examine the susceptibility of larvae and adults of Aedes aegypti (Ae. aegypti) from laboratory and field populations of Lahore city against four major groups of commonly used insecticides; Imidacloprid 5% SC, phenyl-pyrazoles* (fipronil 2.5% EC), pyrethroids (Deltamethrin 2.5% SC) and organophosphates (DDVP 50% EC) world health organization standard procedures were observed.

Methods: For laboratory strain, adults and larvae were collected from the Insectary of the National Institute of Malaria Research and Training (NIMRT), Lahore, Pakistan. Insecticides of four major groups. Larval bioassays were conducted according to the World Health Organization procedure with minor modifications. Larval mortality was finalized after 48 hours for Deltamethrine, Imidacloprid, DDVP, and 72 hours for Fipronil.

Results: Larval and adult toxicity results were different for wild and laboratory strains exposed to different groups of insecticides. Regression analysis showed non-significant trends in mortality. Imidacloprid proved to be the most toxic to wild larval strains of Ae.aegypti collected from different localities of Lahore while Fipronil was also active for wild larval samples.

Conclusion: Deltamethrin showed the least activity against both adults and larval strains. The susceptibility of the field strains was lower than laboratory strains; the ratio varies from insecticide to insecticide.