Efficacy of pyrethroid-treated wide-mesh netting in preventing mosquitoes from passing through and biting

Abstract

Wide-mesh netting of 0.5cm mesh size was impregnated with each of five insecticides (permethrin, cyphenothrin, d-phenothrin, esfenvalerate and fenpropathrin) at various concentration ranging from 0.003125 to 0.025%, and the effect of netting on caged Culex pipiens pallens Coquillett was assessed. The mosquitoes were killed on contact with the treated net as they passed through. The mortality of mosquitoes was parallel to the concentration of an insecticide treated. The biting of Anopheles gambiae Giles on a rabbit caged in a net box treated with each of permethrin (0.6%) and fenpropathrin (0.3 and 0.6%) was also assessed. Most of the mosquitoes died before entering the net box, and the few that entered died before biting. Practical use of pyrethroid-treated wide-mesh bed net for preventing mosquito bite was evaluated from these results.