重庆市2019年登革热疫点灭蚊前媒介伊蚊应急监测结果分析

An analysis of emergency surveillance results of Aedes vector before mosquito control in the epidemic areas of dengue fever outbreak in Chongqing,China,2019

目的调查重庆市各疫点发现登革热首例病例开展灭蚊前的媒介伊蚊应急监测结果,为今后的媒介伊蚊监测和疫区引起登革热本地病例传播风险预警提供依据。方法收集重庆市2019年各疫点首次报告登革热病例后,采取灭蚊措施前的媒介伊蚊监测布雷图指数(BI)和帐诱指数数据,采用SPSS 25.0软件进行数据描述性研究和线性回归分析。结果所有疫点首次应急监测的平均BI值为11.01,平均帐诱指数为5.10只(/顶·h),两者相关系数(r)为0.517,双侧检验P<0.05,BI与帐诱指数呈正相关,且有统计学意义。通过两变量线性回归分析,构建BI与帐诱指数回归方程:y(BI)=7.07+0.82x,F=61.232,P<0.005。在此基础上将重庆市登革热预警风险划分为4个等级。结论将BI和帐诱指数进行分级评估对于登革热疫情的预警具有指示作用,在日常防控中将重庆市BI控制在7以下,帐诱指数控制在3只(/顶·h)以下,对减少登革热本地暴发有参考意义。

Objective To investigate the results of emergency surveillance of Aedes vector before mosquito control after the occurrence of the index case of dengue fever in the epidemic areas of Chongqing,China,and to provide a basis for future surveillance of Aedes vector and early warning research on the risk of local transmission of dengue fever.Methods The surveillance data of Aedes vector were collected after the first cases of dengue fever were reported and before the mosquito control measures were adopted in each epidemic area of Chongqing,including Breteau index(BI)and double mosquito net index(DMNI),and SPSS 25.0 software was used for data description and linear regression analysis.Results The average BI for the first-time emergency surveillance in all epidemic areas was 11.01,and the average was 5.10 mosquitoes/net·hour,with a positive correlation between the two indices(r=0.517,P<0.05).The bivariate linear regression analysis was used to establish the regression equation of BI and DMNI:y(BI)=7.07+0.82x(F=61.232,P<0.005),and the early warning of dengue fever risk in Chongqing was stratified into four levels based on this equation.Conclusion Graded assessment of BI and DMNI acts as an indicator for the early warning of dengue fever risk.For Chongqing,BI controlled below 7 and DMNI controlled below 3 mosquitoes/net·hour may reduce the risk of local outbreak of dengue fever.