论文部分内容阅读
目的对中华按蚊的抗药性进行监测,为合理使用杀虫剂提供科学依据。方法采用成蚊滤纸接触法,按照WHO区分剂量,观察首只蚊虫击倒时间、击倒率和死亡率,以区分剂量判定抗性级别,以半数致死量确定抗性程度。结果监测点中华按蚊对DDT首只蚊虫击倒时间≥10 min,击倒率均<20%,KT50176.86～1 718.63 min;溴氰菊酯和氟氯氰菊酯首只击倒时间为10～32 min和5～33 min,击倒率2.91%～18.35%和2.06%～15.00%;其中溴氰菊酯KT50138.41～6 234.72 min,比1996年调查的KT50提高了20～631倍。中华按蚊对DDT、溴氰菊酯和氟氯氰菊酯区分剂量死亡率均<50%,对马拉硫磷区分剂量死亡率为10.20%～58.66%,其中DDT LC50均>4%,与1993年的调查结果一致;溴氰菊酯LT50684.12 min,比1998年上升了306倍。结论中华按蚊对DDT抗性居高不下,对溴氰菊酯抗药性发展迅猛,可能成为疟疾媒介控制的最大障碍。区分剂量法是监测蚊虫对杀虫剂抗性的有效手段,击倒时间和击倒率的变化是检测早期击倒抗性(kdr)的敏感指标。
Objective To monitor the resistance of Anopheles sinensis to provide a scientific basis for the rational use of insecticides. Methods The mosquito filter paper contact method was used to observe the first mosquitoes’ knockdown time, knockdown rate and mortality according to the dose of WHO. The resistant level was determined by the dose and the resistance was determined by the median lethal dose. Results The first mosquitoes of Anopheles sinensis had the knockdown time of ≥10 min and the knockdown rate of <20%, KT50176.86 ~ 1 718.63 min, respectively. The first knockdown time of deltamethrin and cyfluthrin was 10 ~ 32 min and 5 ~ 33 min. The knockdown rates ranged from 2.91% to 18.35% and from 2.06% to 15.00%. Among them, deltamethrin KT50138.41 ~ 6 234.72 min was 20 ~ 631 times higher than the KT50 survey in 1996. The mortality of Anopheles sinensis against DDT, deltamethrin and cyfluthrin were all less than 50%, and the dose-wise mortality to malathion was 10.20% -58.66%, of which DDT LC50 was> 4% The survey results are consistent; deltamethrin LT50684.12 min, 306 times more than in 1998. Conclusion Anopheles sinensis has high resistance to DDT and rapid development of resistance to deltamethrin, which may be the biggest obstacle to malaria vector control. Dose-based dosimetry is an effective method to monitor insecticide resistance in mosquitoes. The change of knockdown time and knockdown rate is a sensitive indicator of early knockdown resistance (kdr).