Laboratory evaluation on the toxic effects of bednets impregnated with permethrin against malaria mosquitos
Bo, P.; Li, Z.Z.; Wu, Y.G.; Zhang, M.Z.; Li, M.X.; Yang, X.
Southeast Asian Journal of Tropical Medicine and Public Health 27(4): 828-833
1996
ISSN/ISBN: 0125-1562 PMID: 9253892 Document Number: 459297
In the laboratory, bednets impregnated with 250mg ai/m-2 and 500mg ai/m-2 permethrin caused respectively the mean mortalities of 86.6% within 13 months and 87.2% within 17 months on laboratory-bred An. sinensis, while they caused average mortalities of 58.3% within 4 months and 73.8% within 10 months on An. dirus respectively. The bioassay results of KT50 and LT50 on the two species showed that KT50 is shorter than LT50 after exposure to the treated bednets. The ratio is 1:2.16 - 1:3.05. It was observed Anopheles had obviously secondary knocked down after exposure to the treated bednets and there is obvious resurgent after Anopheles have been knocked down. When the temperature goes up the resurgence gets shorter, the resurgence rate gets higher and the mortality gets lower. It showed that permethrin has stronger knocking down effect than killing effect.