首都公共卫生

目的 分析2017—2023年北京市海淀区流感聚集性疫情的流行特征及影响因素,为预防流感暴发疫情和制定防控策略提供参考。方法 资料来源于中国流感监测信息系统和海淀区2017—2023年集中发热疫情现场处置资料,对集中发热疫情中的流感聚集性疫情时间、病原谱、地区和场所分布进行描述流行病学分析,采用χ²检验进行率的比较,多因素logistic回归模型确定疫情发病例数规模和持续时间的影响因素。结果 2017—2023年,海淀区共报告487起流感聚集性疫情;疫情报告时间集中在11月至次年3月(470起,占96.51%);发生场所以小学和幼儿园为主,分别占52.98%和30.18%;各年度流感病毒优势株交替变化,4个流感病毒型别[A(H3N2)亚型、A (H1N1)亚型、B(Victoria)系、B(Yamagata)系]均可引起聚集性疫情高峰;疫情规模以报告发病数10例以下的为主;疫情持续时间以≤7 d为主。与首例病例发病到报告时间≤3 d的疫情相比,报告时间4～7 d和>7 d的更容易发展为发病数≥10例的疫情(OR_4～7d=5.495,95%CI:3.467～8.709;OR_>7d=13.621,95%CI:1.516～122.386),也更容易发展为持续时间>7 d的疫情(OR_4～7d=10.497,95%CI:6.576～16.755;OR_>7d=18.581,95%CI:2.111～163.524)。结论 海淀区流感聚集性疫情冬春季高发,小学、幼儿园是疫情高发场所,及时发现和尽早报告是控制流感聚集性疫情的关键措施。

Objective To analyze the epidemiological characteristics and factors of influenza clustering epidemics in Haidian district,Beijing from 2017 to 2023,and to provide references for the prevention of influenza outbreak epidemics and the formulation of prevention and control strategies.Methods The data were derived from the Chinese Influenza Surveillance Information System and the on-site disposal data of concentrated fever outbreak events in Haidian district from 2017 to 2023.Descriptive epidemiological analysis was carried out on the time,pathogen spectrum,regional and site distributions of influenza clustering epidemics in concentrated fever outbreak events.The χ² test was utilized for the comparison of rates,and a multivariate logistic regression model was employed to determine the influencing factors of the outbreak scale and duration.Results From 2017 to 2023,Haidian district reported a total of 487 influenza cluster outbreaks.The reporting time of the outbreaks was mainly concentrated from November to March of the following year(470 events,96.51%).The main locations of the outbreaks were primary schools and kindergartens(52.98%,30.18%).The dominant influenza virus strains alternated annually,and all four influenza virus types [A(H3N2) subtype,A(H1N1) subtype,B(Victoria) lineage and B(Yamagata)lineage] could cause peak cluster outbreaks.The majority of the outbreaks involved less than 10 reported cases,and the duration of the outbreaks was mostly within 7 days.Compared with the outbreaks where the time from the onset of the first case to reporting was≤3 days,those with a reporting time of 4-7 days and> 7 days were more likely to develop into outbreaks with≥10 cases(OR_{4-7 d}=5.495,95 % CI:3.467-8.709;OR_{>7 d}=13.621,95 % CI:1.516-122.386),and were also more likely to last longer than 7 days(OR_4-7d=10.497,95% CI:6.576-16.755;OR_{>7 d}=18.581,95% CI:2.111-163.524).Conclusions Influenza outbreaks tend to occur frequently in winter and spring in Haidian district,with primary schools and kindergartens being high-risk areas.Early detection and reporting are key measures to control influenza outbreaks.