2015-2018年北京市西城区流感样病例监测情况分析

Analysis on monitoring result of Influenza-like-illness cases in Xicheng District in Beijing,from 2015 to 2018

目的了解2015-2018年北京市西城区流感样病例(Influenza like illness,ILI)报告情况及病原学特征,分析流行趋势及病原学特点,为流感防控提供研究基础。方法采用描述流行病学方法对2015-2018年北京市西城区流感样病例报告数据进行汇总分析,同时分析流感样病例病原学监测情况、流行趋势及病原学特征。结果 2015-2018年3个流感流行季,北京市西城区累计报告流感样病例444 613例,流感样病例百分比1.47%。报告高峰位于历年冬春季,以0~4岁人群居多,占流感样病例总数的57.97%,其次为5~14岁人群(23.63%)。2015-2018年3个流感流行季西城区共采集流感样病例咽拭子样本8 693件,其中流感病毒阳性样本1 489件,阳性率17.13%。3个流行季阳性率呈现高—低—高的现象,2016-2017年流行季阳性率最低。病原学监测结果显示,2015-2016年流行季、2017-2018年流行季均出现乙型流感的流行,2016-2017年流行季乙型流感流行明显减少,高峰期病原型别以甲型H3N2型(66.34%)及甲型H1N1型(28.78%)为主。结论北京市西城区流感样病例流行高峰期为历年冬春季,乙型流感及新型流感病毒的流行可导致高峰期流感样病例咽拭子样本病原学检测阳性率明显升高。应加强流行高峰期流感样病例病原学监测,及时发现病原型别构成变化,做好预测预警。

Objective To study the report and etiological features of Influenza like illness(ILI)cases in Xicheng District in Beijing from 2015 to 2018,then analyze their trends and etiological characteristics to provide research basis for the prevention and control of influenza.Methods The descriptive epidemiology was used to collect and analyze the clinical data of ILI cases in Xicheng District in Beijing from 2015 to 2018.At the same time,the monitoring results of etiology,trends and etiological characteristics were also analyzed.Results There were three epidemic seasons of influenza from 2015 to 2018.Totally 444613 ILI cases were reported in Xicheng District,accounting for 1.47%.The peak of ILI incidence was in winter and spring every year,and the disease especially focused on children aged 0~4 years old,which accounted for 57.97%of the total cases,followed by people aged 5~14 years old(23.63%).Totally 8693 throat swab samples were collected,of which 1498 samples were positive,and the positive rate was 17.13%.The positive rates of those three epidemic seasons took on"high-low-high"phenomenon.And the positive rate was the lowest during the epidemic season of 2016-2017.The monitoring results of etiology showed that influenza B virus was prevalent during the epidemic seasons of 2015-2016 and 2017-2018.And in the epidemic season of 2016-2017,influenza B was not prevalent.Influenza A(H3 N2)(66.34%)and A(H1 N1)(28.78%)were mainly concentrated on the peak days.Conclusion Winter and spring meet the peak of reported ILI cases in Xicheng District.The prevalent of influenza B and new type virus can lead to high positive rate of throat swab samples.We should make more efforts on case surveillance,especially in epidemic season,in order to detect the changes of prevalent types and do well in forecast and early warning.