南昌市登革热传播媒介白纹伊蚊密度、抗药性及病原体携带监测研究

Study on the seasonal dynamical,dengue virus carrying and insecticides resistance of Aedes albopictus in Nanchang

目的掌握南昌地区白纹伊蚊密度、季节消长规律、登革热病毒携带以及对常用杀虫剂的抗药性程度,为合理选择和使用杀虫剂,科学防控登革热提供科学依据。方法采用WHO推荐的幼虫浸渍法和成蚊接触筒法分别测定白纹伊蚊幼虫和成蚊的抗药性;密度监测:成蚊采用双层叠帐法,幼虫分别采用布雷图指数法(BI)、勺舀法和路径指数法;白纹伊蚊登革热病毒携带检测采用RT-PCR核酸检测。结果2018年南昌地区白纹伊蚊成蚊呈单峰活动趋势,活动最高峰为6月份,全年平均帐诱指数为2.76只/(顶·h),平均布雷图指数(BI)为6.18,平均路径指数为4.67处/km,居民区帐诱指数、BI和路径指数远高于工地和公园生境。白纹伊蚊成蚊对溴氰菊酯和高效氯氰菊酯产生抗性,对马拉硫磷、氯菊酯、杀螟硫磷和残杀威表现敏感;白纹伊蚊幼虫除对溴氰菊酯表现为敏感外,对DDVP等其他6种杀虫剂分别表现出不同的抗性,抗性倍数处于9.09~76.19之间。南昌地区野外品系白纹伊蚊未检测到登革热病毒。结论一旦有登革热病例的输入,南昌地区存在登革热传播风险,应停用已产生高度抗药性的氯氰菊酯、残杀威等杀虫剂,重点清除居民区生境内白纹伊蚊孳生地,及时根据监测结果评估登革热发生或流行的风险,可为南昌地区登革热疫情的预测预警提供科学依据。

To investigate the seasonal dynamic, insecticide resistant level and field adults dengue virus carrier of A. albopictus in Nanchang city and provide evidence for rational application of insecticides and controlling methods of dengue and dengue vectors. Insecticides resistance was tested with exposure tubes on adults and dipping method on larvae, adult density surveillance was conducted with double stack method recommended by WHO. Breteau index, spoon larvae method and route index methods were used for larvae monitoring. Aedes albopictus dengue virus was detected by RT-PCR. In 2018, the adult Aedes albopictus showed a single peak activity trend in Nanchang area, with the highest peak activity in June. The average trap index, Bray index (BI) and route index was 2.67,6.18 and 4.67 respectively. The residential area trap index, BI and route index were much higher than those of construction sites and park habitats. The Adults were resistance to deltamethrin and lambda^cypermethrin, and sensitive to malathion, permethrin, fenthion, and paracetamol;while Larvae of Aedes albopictus were showed low-medium-high resistance to 6 other pesticides except for deltamethrin, with a resistance index between 9.09-76.19 times. In addition dengue virus was not detected in the wild line Aedes albopictus in Nanchang. In conclusion,there is a risk of dengue transmission in Nanchang,once there is a imported case dengue fever. High-resistance insecticides such as Cypermethrin and Propoxur should be prohibited immediately;Eliminating mosquitoes breeding sites should be continuously in residential areas;The timely risk assessment of the risk of dengue fever occurrence or epidemic based on the monitoring results can provide a scientific basis for the prediction and early warning of dengue fever in Nanchang.