中华按蚊对DDT和溴氰菊酯抗药性的现场调查

Field survey of resistance of Anepheles sinensis to DDT and permetherin

目的了解中华按蚊对DDT和溴氰菊酯的抗药性,为制定防制策略提供科学依据。方法采用WHO成蚊滤纸接触法,以区分剂量判定抗性级别,以LD50确定抗性程度。结果中华按蚊对DDT和溴氰菊酯区分剂量击倒率均<20%,死亡率均<50%,具有很高的抗药性。DDT的LC50>4%,与1996年调查一致;溴氰菊酯LT50684.12min,比1998年提高306倍。结论DDT停用多年后抗药性未明显下降,溴氰菊酯的抗药性则呈上百倍的速度发展,对DDT和溴氰菊酯的击倒抗性(kdr)应予高度重视。

Objective To understand the resistance of Anopheles sinensis to DDT and deltamethrin, provide scientific evidence for formulating the control strategy. Methods Filter paer traping technique advocated by WHO was used to test the resistance level of adult mosquitos to pesiticides for acertain the the grade of resistance by determination of the median lethal dose （LD50）. Results The drug resistance of Anopheles sinensis was very high for that the dosage knockdown rates to DDT and deltamethfin were both less than 20% and the mortality rate was both less than 50%. The LC50 of DDT was over 4%. The LTs0 of deltamethrin was 684.12 min, 306 times higher than that in 1999. Condusion Though the drug resistance has not decreased obviously many years after the terminating use of DDT. The resistance to deltamethrin has increased at the hundred fold speed, so we should think highly of the kdr to DDT and Dehamethrin.