北京市2016-2017年流感流行季一起流感暴发疫情分析

Analysis on an outbreak of influenza outbreak in the flu season of Beijing during 2016 -2017

目的对北京市2016-2017年流感流行季首起流感暴发疫情开展流行病学调查，并了解学生流感疫苗接种情况、家长疫苗接种知识知晓率和接种意愿，为相关疫情防控提供参考。方法通过现场流行病学调查，了解疫情发生过程与学生流感疫苗接种情况。采集病例标本开展流感病毒核酸检测，并对阳性标本开展流感病毒HA基因测定分析。对病例家长开展电话访谈，了解家长对流感及疫苗接种的认知。结果本起疫情由甲型H3N2亚型流感病毒引起，疫情发生班级学生罹患率41．03％。疫情发生班级整体疫苗接种率10．26％，病例接种率6．25％，非病例接种率13．04％，全校无疫情班级疫苗接种率19．53％。病例家长不能区分普通感冒和流感的占40％，病例未接种疫苗原因主要为：认为接种后无效（占53．33％）；接种疫苗后会导致患病（占33．33％）；患病能增加抵抗力，不必要接种（占26．67％）；对疫苗不信任（占26．67％）。结论应加强流感及疫苗接种知识宣传，提高学生及家长防病意识。流感流行季前，应尽快组织学生接种流感疫苗，提高接种率。

Objective To investigate the first influenza-like illness outbreak, and to survey the influenza vaccination rate, awareness rate and willingness among parents for vaccination, so as to provide evidences for the prevention and control of influenza outbreaks. Methods The epidemiological investigation was carried out to collect the information on the outbreak and the status of influenza vaccination. Samples were collected for viral nucleic acid analysis of influenza and HA gene from the positive samples were sequenced. The awareness of influenza and vaccination was investigated through telephone interviews for the parents of the cases. Results The outbreak was caused by influenza virus （A/H3N2）. The attack rate was 41.03% in the affected class. The vaccination rates of the class and other classes were 10.26% and 19.53% respectively. The vaccination rates in cases and other students were 6.25% and 13.04% respectively. The parents of the cases who could not distinguish common cold from influenza accounted for 40.00%. There were four reasons for case unvaccinated, they thought vaccination is invalid （53.33%）, vaccination leads to illness （33.33%）, Illness increases resistance （26.67%）, and don＇t believe vaccine （26.67%）. Conclusions It is necessary to pay more important on knowledge propaganda about the influenza prevention and the effects of vaccination. It is also important to improve the awareness of disease prevention among students and parents. Before flu season, we should organize vaccination in students as soon as possible so as to improve vaccination rate.