云南省普洱市澜沧县2014—2018年登革热媒介监测分析

Vector surveillance of dengue fever in Lancang County of Pu′er,Yunnan, 2014-2018

目的了解澜沧县登革热媒介种类、分布、季节消长和孳生习性,为登革热防控提供科学依据。方法采用布雷图指数法,调查各类型积水容器的伊蚊幼虫孳生和组成情况,采集阳性容器内的幼虫进行鉴定,计算布雷图指数、容器指数、房屋指数和伊蚊幼虫阳性率。结果2014—2018年共调查23 750户,阳性1 946户,调查积水容器59 859个,其中阳性容器2 229个,总布雷图指数(Breteau index,BI)为9.39,总容器指数(container index,CI)为3.72,总房屋指数(house index,HI)为8.19。2017、2018年全年均有伊蚊幼虫孳生,5月BI开始升高,9月为密度高峰,10月开始下降。永久性积水、花瓶、废旧轮胎、水桶、废弃瓶/罐和其他(暂时)容器的幼虫阳性率分别是0.49%、2.17%、6.51%、2.77%、3.01%和1.43%。2 229个阳性容器中,经虫种鉴定白纹伊蚊2 226个占99.87%,埃及伊蚊3个占0.13%。结论普洱市澜沧县首次发现登革热重要传播媒介埃及伊蚊。白纹伊蚊广泛分布城区和口岸,且密度较高,是当地的优势伊蚊蚊种,因登革热输入病例引起本地暴发的风险高。应加强媒介伊蚊监测和管理,采取物理、化学等多种手段有效控制伊蚊,降低登革热疫情发生的风险。

Objective To know species composition,distribution,seasonal density and breeding custom of dengue vector mosquitoes in Lancang County,in order to provide a scientific basis for control of mosquitoes and dengue fever.Methods The Breatu index method was used to surveillance the breeding sites and composition of Aedes larvae in all types of water containers in Lancang County,during 2014 to 2018.Larvae indices,the Breatu index,house index,container index and positive rate of larvae breeding site,were calculated.Results In this study,a total of 23 750 households were surveyed,among which 1 946 households were confirmed positive during 2014 to 2018.In total,59 859 water containers were found,of which 2 229 were positive.The BI,CI and HI were 9.39,3.72,and 8.19,respectively.In 2017 and 2018,there were breeding of Aedes mosquito larvae all year round.BI began to increase in May,peaked in September,and decreased in October.The positive rate of breeding containers among tanks,vases,used tires,buckets,discards,and other water storage containers,were 0.49%,2.17%,6.51%,2.77%,3.01%and 1.43%,respectively.And 2 229 of positive containers were confirmed,of which 2 226 containers were Aedes Albopictus(99.87%),3 containers were Ae.Aegypti(0.13%).Conclusion Aedes aegypti,the efficient vectors for dengue fever,was first found in Lancang County.Ae.albopictus is the dominant species distributing in whole county.After occurring the imported cases of dengue,the risk of outbreak dengue is very high in Lancang.Vector and case surveillance should be enhanced.All kinds of method should be used to reduce the density of Aedes mosquito.