2017—2018年北京市西城区流感流行特征

Epidemic characteristics on influenza in Xicheng District of Beijing from 2017-2018

目的 分析2017-2018年北京市西城区流感流行及病原学分析情况,为今后流感防控工作提供参考依据。方法 利用《北京市医疗机构传染病监测预警系统》中流感样病例(ILI)及流感样病例百分比(ILI%)的数据、流感实验室病原学监测数据以及北京市西城区聚集性疫情报告情况,综合分析2017-2018年北京市西城区流感流行特征和流感病毒的构成情况。结果 2017年第27周-2018年第26周,ILI数、ILI%呈明显冬春季高发特点,在元旦前后达到流行高峰,15岁以下为流感高发年龄,占流感样病例总数的77.83%。本流行季甲型H3N2亚型、甲型H1N1亚型、乙型Yamagata系3种流感病毒亚型共同流行。共报告流感病毒引起的聚集性疫情58起,有43起小学报告疫情,占74.14%,39起由乙型Yamagata系引起,占67.24%。ILI数、ILI%与流感病毒阳性率流行趋势一致(r=0.635、0.617,均P<0.01)。结论 2017-2018年北京市西城区流感聚集性疫情高峰出现在元旦前后,今后应继续高度关注流感病毒活动情况,加强监测数据的分析与利用,以便及时开展学校、幼儿园等重点场所流感聚集性疫情的调查处置工作。

Objective To analyze the epidemic and etiological characteristics on influenza in Xicheng district of Beijing from 2017-2018,provide reference for the future work of influenza prevention and control.Methods The data of influenza-like illness(ILI)and the percent of ILI(ILI%)from the Early warning system for infectious disease in medical institutions in Beijing,influenza laboratory pathogenic monitoring data and aggregated epidemic reports in Xicheng District of Beijing were used to comprehensively analyze the influenza epidemic characteristics and influenza virus composition in Xicheng District of Beijing from 2017-2018.Results From 27th week in 2017 to 26th week in 2018,the number of ILI cases and ILI%showed n obvious characteristics of increase in winter and spring,reaching the peak around New Year's Day.The majority of cases were people below 15 years old,accounting for 77.83%of the total ILI cases.During this year,three subtypes of influenza virus were observed,including A(H3N2),A(H3N2)and B Yamagata lineage virus.58 influenza aggregated epidemic were reported,43(74.14%)occurred in primary schools and 39(67.24%)were caused by B Yamagata lineage virus.the number of ILI cases and ILI%were consistent with the epidemic trend of influenza virus positive rate(r=0.635,0.617,both P<0.01).Conclusion From 2017-2018,the peak of influenza aggregated epidemic in Xicheng District of Beijing appears around New Year's Day.It is necessary to continue to pay close attention to influenza virus activity,and to strengthen the analysis and utilization of monitoring data,and also to carry out the influenza aggregated epidemic investigation and disposal work timely in schools and kindergartens.