2017年杭州市登革热暴发疫情防控效果评价

Assessment on the control effect of dengue fever outbreak in Hangzhou in 2017

目的对杭州市登革热暴发疫情的防控效果开展定量评价。方法从中国疾病预防控制信息系统获取杭州市2017年按日报告的登革热本地发病数,从杭州市气象局获取同期气温和降雨量数据,描述分析气温和降雨量与登革热发病关系,拟合发病数与时间指数模型(Ŷ=β0e^β1x),预测疾病自然状态下发病高峰,并利用回归系数反映各时期登革热疫情发展速度,以此来定量评价不同时期防控措施实施效果。结果该次登革热疫情累计发病1174例,发病数随时间呈先升后降,在第5代周期达到发病高峰336例。本次疫情期间平均气温随时间呈直线下降,最高气温33.35℃,最低气温16.50℃;累计降雨量随时间呈波浪式上升。本次疫情实际发病高峰较预测高峰下降97.40%,疫情发展速度从干预前的3.39逐步减小到干预后的1.39;公布疫情后疫点控制效果明显好于疫情公布前,283个疫点中控制无效的疫点比例从64.15%下降到5.22%,差异有统计学意义(χ^2=109.903,P<0.01)。结论2017年杭州市综合防控措施对登革热暴发疫情起到了削峰减速的作用。

Objective To evaluate quantificationally the effectiveness of controlling dengue fever outbreak in Hangzhou.Methods Local cases of dengue fever reported by day in Hangzhou in 2017 were collected from information system of Chinese Center for Disease Control and Prevention.The temperature and quantity of rainfall at same period were collected from Hangzhou Meteorological Administration.The relationship of the incidence of dengue fever and temperature as well as rainfall quantity was analyzed.Exponential models of dengue cases and generation times(Ŷ=β0e^β1x)were fitted,and the peak onset of dengue fever under the natural conditions was forecasted by the model.The development speeds of dengue fever outbreak were calculated by the regression coefficient,so as to quantitatively evaluate the effect of control measures.Results A total of 1174 cases of dengue fever were reported in Hangzhou in 2017.Cases increased early and then decreased late with time,which were at the peak(336 cases)in the 5th generation time.Meanwhile the average temperature dropped linearly with time with the highest of 33.35℃and the lowest of 16.50℃.The cumulative quantity of rainfall increased in waves.The actual incidence peak reduced 97.40%compared with the predictable peak,and the development speed decreased from 3.39 to 1.39 after the intervention.The declining trend was more significant after publicly announcing local dengue fever outbreak,and the ratio of ineffective controlling epidemic places among 283 places declined from 64.15%to 5.22%(χ^2=109.903,P<0.01).Conclusions The control measures by Hangzhou's government effectively reduced the peak and speed of local dengue fever outbreak in 2017.