Abstract: Objective To determine the susceptibility of Anopheles sinensis to DDT, deltamethrin, beta - cypermethrin,permethrin, and propoxur in Shenyang, China, and to provide a scientific basis for rational and effective use of pesticides in the control ofAn. sinensisand to reduce the outbreak of malaria in Shenyang area.Methods The adult mosquito filter paper contact method recommended by WHO was used in determination of resistance, given WHO distinguishing dosage. The insecticide resistance ofAn. sinensiswas evaluated by determination of resistance level, first knock-out time, and knock-out rates at different times. Results The mortality rates ofAn. sinensisafter 24 hours of treatment with deltamethrin, beta-cypermethrin, permethrin,propoxur, and DDT were 87% , 79% , 100% , 100% , and 100% , respectively.An. sinensiswas preliminarily resistant (M) to deltamethrin, resistant (R) to beta-cypermethrin, and susceptible (S) to DDT, permethrin, and propoxur. The median knock-out times (KT50) and the 95% confidence intervals were 24.4025 (27.2605-21.8442), 27.4794 (32.2923-23.3838), 19.6297(22.0655-17.4628), 9.0588 (9.5893-8.5578), and 23.8534 (26.1363-21.7699) min, respectively. The insecticide with the lowest KT50 was propoxur (9.0588 min), while the one with the highest KT50 was beta-cypermethrin (27.4794 min).Conclusion Anopheles sinensisin Shenyang has developed a certain level of resistance to beta-cypermethrin. Thus, it is necessary to use insecticides properly and to delay the development of insecticide resistance. An. sinensisis relatively susceptible to propoxur, indicating that propoxur can be applied as the major insecticide in the control ofAn. sinensisat the present time.

Key words: Malaria, Anopheles sinensis, Insecticide, Insecticide resistance

摘要： 目的 了解沈阳地区中华按蚊对DDT、溴氰菊酯、高效氯氰菊酯、氯菊酯、残杀威的抗药性,为合理使用有效的杀虫剂控制中华按蚊提供科学依据,减少疟疾在沈阳地区的暴发流行。方法 采用WHO成蚊滤纸接触法,以WHO区分剂量进行测定,通过抗性级别、开始击倒时间、不同时间的击倒率评价按蚊对杀虫剂的抗药性。结果 中华按蚊对溴氰菊酯、高效氯氰菊酯、氯菊酯、残杀威、DDT 24 h的死亡率分别为87%、79%、100%、100%和100%。中华按蚊对溴氰菊酯为初步抗性群体(M),对高效氯氰菊酯为抗性群体(R),对氯菊酯、残杀威、DDT为敏感群体(S)。半数击倒时间(KT50)及其95%置信区间分别为24.4025(27.2605～21.8442)、27.4794(32.2923～23.3838)、19.6297(22.0655～17.4628)、9.0588(9.5893～8.5578)和23.8534(26.1363～21.7699)min。其中残杀威的KT50值最小,为9.0588 min,高效氯氰菊酯的KT50值最大,为27.4794 min。结论 在沈阳地区中华按蚊对高效氯氰菊酯产生了一定抗药性。因此,应合理使用杀虫剂,以延缓抗药性的发展;中华按蚊对残杀威相对较敏感,可作为现阶段主要的杀虫剂使用。

关键词: 疟疾, 中华按蚊, 杀虫剂, 抗药性