Evaluation of permethrin‐impregnated mosquito‐nets against mosquitoes in China

Abstract

In Yishan County, Guangxi Province, China, where malaria and Brugian filariasis are transmitted by vectors belonging to the Anopheles hyrcanus Pallas group, a study was conducted from June to November 1986 to evaluate the effectiveness of permethrin-impregnated mosquito bednets to reduce man/vector contact. In three experimental villages a total of 246 mosquito nets were treated with permethrin EC at a dosage of 0.5 g/m2. Control bioassays (1 h exposure) of treated nets gave up to 100% mortality of Armigeres subalbatus (Coquillett), Anopheles sinensis Wiedemann and Culex tritaeniorhynchus Giles for up to 19 weeks. During 5 months evaluation in the villages, permethrin-impregnated mosquito-nets reduced the number of mosquitoes found inside nets by 99.3% for Culex quinquefasciatus Say, by 94.4% for Anopheles sinensis Wiedemann and by 75% for Anopheles lesteri anthropophagus Xu & Feng. This measure could thus be considered an appropriate means of controlling vectors in villages.