湖北部分地区中华按蚊对溴氰菊酯抗药性的现场调查

Field survey of resistance of Anopheles sinensis to deltamethrin in Hubei Province

目的了解中华按蚊对溴氰菊酯抗药性,为合理使用杀虫剂提供科学依据。方法采用WHO成蚊滤纸接触法,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,半数致死量判定抗性程度。结果襄阳、广水、京山、安陆、孝昌、仙桃和恩施等地中华按蚊对溴氰菊酯首只蚊虫击倒时间分别为32、19、25、10、15、10和10min,60min击倒率分别为3.13、10.31、16.04、18.35、7.00、4.95和6.12%;京山、安陆、孝昌、仙桃和恩施等地中华按蚊对溴氰菊酯KT50分别为227.78、138.41、263.41、6234.72和1575.88min,比1996年提高20～631倍;京山县中华按蚊LT50684.12min,比1998年提高306倍;7地区中华按蚊对溴氰菊酯区分剂量死亡率均<50%,为高抗群体,比1993年提高2～3个抗性级别。结论湖北地区中华按蚊对溴氰菊酯抗击倒力强,抗性程度高,抗性发展快,应加强监测,现场应用宜适当加大使用剂量,确保防制效果。

Aim To understand the resistance of Anopheles sinensis to deltamethrin. Methods Adult Anopheles filter contact method recommended by WHO was used to observe the knockdown rate, the knockdown time of the first Ano pheles and the mortality of the mosquitoes. The resistance level was determined by tentative diagnostic dose and the resistance degree was determned by LD50. Results The knockdown time of the first Anopheles of seven monitoring spots were 10- 32rain,the knockdown rate of these spots were 3.13-18.35% ,KTs0 of Anopheles sinensis to dehamethrin were 138.41 - 6234.72min,an increase of 20-631times than that in 1996;LT50 of Anopheles sinensis of Jingshan county was 684.12min,an increase of 306 times than that in 1998;The discrimination dosage mortality ofA nopheles sinensis to deltamethrin were all less than 50%. Conclusion The Anti-knockdown capability and the resistance level ofA nopheles sinensis to deltamethrin were both high in Hubei, to guide the use of deltam ethrin, the monitoring work should be strengthened.