Laboratory studies of pyrethroid-netting combinations to kill mosquitoes.

Bioassays of cotton or synthetic netting, impregnated with one of two formulations of deltamethrin or a formulation of lambda-cyhalothrin, showed that the order of merit of these insecticides varied significantly with the type of netting used. Washing reduced the insecticidal power of all combinations of insecticide and netting. Halving the time of exposure and doubling the dose tended to increase the mortality. Different An. stephensi strains varied significantly in susceptibility. Netting (5 to 8 mm mesh) impregnated with deltamethrin was effective in killing mosquitoes which penetrated the netting in search of an animal host.