云南省边境地区埃及伊蚊和白纹伊蚊孳生特征调查

INVESTIGATION ON THE BREEDING SITES OF AEDES AEGYPTI AND AEDES ALBOPICTUS IN BORDER AREAS OF YUNNAN PROVINCE

埃及伊蚊和白纹伊蚊是登革热的主要传播媒介,蚊虫孳生情况的持续调查和分析,有助于对种群变化进行实时监控,从而为登革热的防治提供理论依据。2017—2020年,每年9—10月在云南省西双版纳州(勐腊县、景洪市、勐海县),临沧市(镇康县南伞镇、耿马县孟定镇),德宏州(瑞丽市)共6个市(县)调查埃及伊蚊和白纹伊蚊孳生地类型并捕捞幼虫,对4龄幼虫分类鉴定以观察两种伊蚊特征。结果显示,此次在所调查的6个市(县)均发现两种伊蚊孳生地,共560个。孳生地类型以家用水桶类最多,占比44.82%。边境各地区居民区调查发现埃及伊蚊孳生地占比33.64%,商业区埃及伊蚊占比48.89%,两种调查地埃及伊蚊数量差异存在统计学意义,在商业区埃及伊蚊占比高于居民区。2017年西双版纳州和瑞丽市白纹伊蚊孳生地占比分别为75.51%和67.44%,2020年为36.67%和38.10%,说明两地白纹伊蚊构成比下降。两地区埃及伊蚊孳生地占比由2017年的18.37%和16.28%增长为2020年的43.33%和42.85%,说明埃及伊蚊构成比上升。结果表明,由于埃及伊蚊比白纹伊蚊传播登革热的能力更强,2020年的西双版纳州和瑞丽市较2017年,商业区较居民区暴发登革热的潜在风险更高。

Ae.aegypti and Ae.albopictus are the main vectors of dengue fever.Continuous investigation and analysis of the mosquito breeding sites will help real-time monitor the population changes and provide a theoretical basis for dengue fever prevention.Ae.aegypti and Ae.albopictus larvae were collected at Xishuangbanna Prefecture(Mengla County,Jinghong County,Menghai County),Lincang City(Nansan Town,Mengding Town)and Dehong Prefecture(Ruili County)during September to October among 2017-2020.The 4th instar larvae were identified to observe the distribution of Ae.aegypti and Ae.albopictus.In this investigation the breeding sites of Ae.aegypti and Ae.albopictus were found in all the surveyed cities.A total of 560 breeding sites were found in the four-year survey.Buckets containers accounted for 44.82%,which were the most common type of breeding sites in this investigation.Ae.aegypti caught in the residential areas accounted for 33.64%,the commercial areas accounted for 48.89%.There is a statistical difference in the number of Ae.aegypti at the two surveyed areas(χ^(2)=10.956,P=0.0009328),the proportion of Ae.aegypti in commercial areas is higher than which in residential areas.In 2017,the proportions of Ae.albopictus-positive sites were 75.51%and 67.44%in Xishuangbanna and Ruili,respectively,compared with 36.67%and 38.10%in 2020(Xishuangbanna:χ^(2)=15.785,P=0.00007095;Ruili City:χ^(2)=4.9712,P=0.02577),which indicating that the composition ratio of Ae.albopictus in the two places has decreased.The proportion of Ae.aegypti-positive areas in the two regions increased from 18.37%and 16.28%in 2017 to 43.33%and 42.85%in 2020.(Xishuangbanna:χ^(2)=7.5083,P=0.00614;Ruili City:χ^(2)=5.5782,P=0.01819).This shows that the composition ratio of Ae.aegypti has increased.Because Ae.aegypti has a stronger ability to transmit dengue fever than Ae.Albopictus,commercial areas are at a higher risk of dengue fever than residential areas.Compared with 2017,the potential risk of dengue fever in Xishuangbanna and Ruili is higher in 2020.