中华按蚊对杀虫剂敏感性调查

Investigation on the Sensitivity of Anopheles sinensis to Insecticide

目的分析河南省疟疾媒介中华按蚊对DDT、氟氯氰菊酯、马拉硫磷和溴氰菊酯的敏感性,为制定疟疾媒介防制对策提供依据。方法2009年6月在河南省桐柏县、淮滨县和永城市3个县(市)现场分别捕获吸血后中华按蚊成蚊417、421和433只,采用WHO推荐的成蚊滤纸接触法进行检测,计算中华按蚊分别接触4%DDT(1.428g/m2),0.15%氟氯氰菊酯(0.0 534 g/m2),5%马拉硫磷(1.78 g/m2)和0.05%溴氰菊酯(0.0 178 g/m2)的半数击倒时间(KT50)和24 h后死亡率。根据死亡率判定抗性级别,死亡率98%～100%为敏感群体(S级),80%～97%为初步抗性群体(M级),80%以下为抗性群体(R级)。结果桐柏县、淮滨县和永城市3个县(市)中华按蚊接触DDT的KT50分别为206.13、877.04和826.81 min;接触氟氯氢菊酯的KT50分别为206.43、85.39和427.60 min;接触马拉硫磷的KT50分别为19.98、48.05和97.79 min;接触溴氰菊酯的KT50分别为1122.50、89.65和960 min。接触4%DDT 24 h死亡率分别为82.52%、57.41%和65.69%,抗性级别分别为M、R和R级;接触0.15%氟氯氰菊酯24 h死亡率分别为91.89%、85.00%和72.73%,抗性级别分别为M、M和R级;接触5%马拉硫磷24h死亡率分别为95.10%、95.37%和93.16%,抗性级别均为M级;接触0.05%溴氰菊酯24h死亡率分别为92.08%、77.14%和63.46%,抗性级别分别为M、R和R级。结论河南省中华按蚊对DDT、氟氯氰菊酯和溴氰菊酯已产生较强抗性,对马拉硫磷产生初步抗性。

Objective To investigate the sensitivity of Anopheles sinensis to DDT, cyfluthrin, malathion and deltamethrin. Methods In June 2009, 417, 421 and 433 mosquitoes were respectively captured from the fields of Tong- bai county, Huaibin county, Yongcheng city, and tested by the adult Anopheles filter contact method recommended by WHO. The KTso and the mortality rate of 24 h-post-exposure to 4% DDT （1.428 g/m^2）, 0.15% cyfluthfin （0.0534 g/m^2）, 5% malathion （1.78 g/m^2）, 0.05% deltamethrin （0.0 178 g/m^2） were calculated. The resistance level was graded as sensitive group （S） with a mortality rate of 98%-100%, preliminary resistance group （M） with mortality rate of 80%-97%, and resis- tance group （R） with mortality rate lower than 80%. Results The KT50 of An. sinensis to DDT in Tongbai, Huaibin and Yongcheng were 206.13, 877.04 and 826.81 min, respectively; the KTs to cyfluthrin was 206.43, 85.39, and 427.60 min, re- spectively; the KT50 to malathion was 19.98, 48.05 and 97.79 min, respectively; the KT50 to dehamethrin was 1122.50, 89.65, and 960min, respectively. The mortality rate of An. sinensis in 24h-post-exposure to 4% DDT was 82.52%, 57.41%, and 65.69%, and the resistance degree was judged as M, R and R, respectively. That to 0.15% cyfluthrin was 91.89%, 85.00%, and 72.73%, with a resistance degree of M, M, and R, respectively. That to 5% malathion was 95.10%, 95.37%, and 93.16%, all with a resistance degree of M. That to 0.05% dehamethrin was 92.08%, 77.14%, and 63.46%, with a resistance degree of M, R and R, respectively. Conclusion An.sinensis in Henan Province has developed high degree of resistance to DDT, cyfluthrin and dehamethrin, and certain degree of resistance to malathion