2017—2022年北京市西城区聚集性腹泻疫情病毒检测结果分析

Viral test in clusters of diarrhea in Xicheng Distract of Beijing in 2017-2022

目的分析2017—2022年北京市西城区聚集性腹泻疫情流行特征和病原体变化,为制定疫情防控政策提供依据。方法收集2017年1月至2022年12月北京市西城区聚集性腹泻疫情患者便标本,同时采集部分单位厨师便标本,使用荧光定量PCR检测轮状病毒、诺如病毒、札如病毒、星状病毒及腺病毒。对于诺如病毒阳性标本,使用RT-PCR扩增ORF1/ORF2区核酸片段,测定序列并分型。结果2017—2022年北京市西城区报告401起聚集性腹泻疫情,幼儿园、小学及中学报告369起,占比92.02%,每千人患病人数分别是4.14、2.13、0.69人;15起疫情中74名厨师检出诺如病毒阳性,阳性率为8.67%;按病原体看,诺如病毒引起疫情占比最多,呈逐年下降趋势,且每年至少有3种GⅡ亚型诺如病毒检出。结论幼儿园及中小学是北京市西城区腹泻疫情发生主要场所;未明原因引起腹泻疫情呈上升趋势,应及更新检测方法,扩大病原体监测种类范围;北京地区诺如病毒流行呈“多亚型并存,亚型间交替出现”的状况。新亚型的引入或已有亚型间的重组需引起密切关注。

Objective To analyze the epidemiological patterns and pathogens of clusters of diarrhea in Xicheng Distract,Beijing during 2017-2022,in order to update the policy of prevention.Mehods Between January 2017 and December 2022,stool samples of patients and partly cooks in clusters of diarrhea were collected and tested by Real-time PCR for Rotavirus,Norovirus,Adenovirus,Sapovirus and Astrovirus.Part of ORF1/ORF2 from Norovirus positive samples were amplified using RT-PCR.PCR products were sequenced and the genetypes were determined.Results Four hundreds and one clusters of diarrheas were reported.Among them,369 were reported in kindergartens,primary schools and secondary schools.The morbidities were 4.14,2.13 and 0.69 per thousand,respectively.Seventy four cooks in 15 clusters of diarrhea were Norovirus positive.The rate was 8.67%.Among these pathogens,Norovirus had the largest proportion,but the trend was declining.At least three kinds of genetype of GⅡNorovirus were detected every year.Conclusion Clusters of diarrhea mainly occurred in kindergartens,primary schools and secondary schools.Result from the increasing proportions of unknowncause clusters of diarrhea,the testing methods and scopes of pathogens should be extended.Diverse genetypes of Norovirus coexist and alternate in Beijing.So appearance of new genetypes and recombination of existed ones of Norovirus should be closely concerned.