广州市登革热散发和暴发布雷图指数临界值分析

摘要

目的 了解广州市登革热散发和暴发蚊媒密度指标布雷图指数(BI)的临界值.方法 以广州市为研究区域,对2006-2012年国家传染病监测与管理系统中广州市登革热病例进行描述性分析,采用受试者工作特征(ROC)曲线判断登革热在街道内散发与暴发BI的临界值.结果 2006-2012年广州市共报告本地病例1 038例,共有71次登革热暴发,259次散发.ROC曲线分析显示,BI值为6.4时预测散发的约登指数最高(1.469),灵敏度为67.8％,特异度为79.1％;BI为9.5时预测暴发的约登指数最高(1.726),灵敏度为81.7％,特异度为90.9％.结论 预测登革热散发和暴发的BI临界值分别可定为5.0和9.5,实际工作中,应根据监测目的和人力物力对临界值进行调整,以得到更为合理的灵敏度和特异度.%Objective To understand the threshold of Breteau Index (BI) on Dengue fever outbreak in Guangzhou.Methods Dengue cases from Guangzhou during 2006 to 2012 in the National Infectious Disease Report and Management System were collected and described.Receiveroperating characteristic (ROC) curve was used to judge the threshold of BI on the outbreaks of Dengue fever.Results A total of 1 038 local cases were reported from 2006 to 2012 in Guangzhou city,with a total of 71 outbreaks and 259 sporadic episodes.Data from the ROC curve analysis showed that the highest Youden index that BI predicting Dengue fever outbreaks or sporadic were 6.4 and 9.5,respectively.When using BI=6.4 in predicting the sporadic case of Dengue,sensitivity and specificity were 67.8％,79.1％,respectively.When using BI=9.5 in predicting the outbreaks of Dengue,sensitivity and specificity were 81.7％,90.9％,respectively.Conclusion Both BI=5.0 and BI=9.5 showed effects on predicting the nature of sporadic or outbreak on Dengue,suggesting that the threshold need to be monitored,according to the purpose of control and availability of manpower,in order to get better sensitivity and specificity.