2021年浙江省湖州市致泻性大肠埃希菌病原学特征分析

Etiological characteristics of diarrheagenic Escherichia coli in Huzhou City,Zhejiang Province in 2021

目的研究2021年浙江省湖州市致泻性大肠埃希菌分离株的检出情况、主要毒力基因、耐药性以及分子分型特征。方法对2021年哨点医院腹泻患者粪便标本和市场采集的食品标本进行分离,运用多重荧光定量PCR方法检测其毒力基因,并对其中104株进行耐药性检测和脉冲场凝胶电泳分子分型。结果病例源中肠聚集性大肠埃希菌(EAEC)检出率最高为60.66%,食品源中也是EAEC检出率最高,为92.86%。DEC引起的发病人群以20岁~39岁年龄组最高,发病高峰在6月—8月。耐药率最高依次为氨苄西林(63.46%)、四环素(62.50%)、萘啶酸(57.69%)。经Xba I酶切后,对EAEC和ETEC进行分别聚类,EAEC相似度为41.7%~100.0%,ETEC相似度为40.7%~100.0%。结论2021年湖州市检出的致泻性大肠埃希菌以EAEC为主,对氨苄西林的耐药率最高。建立本地PFGE分子分型数据库,为DEC防控提供数据支撑。

Objective This paper aims to investigate the detection,main virulence genes,antimicrobial resistance and molecular characteristics of diarrheagenic Escherichia coli in Huzhou City of Zhejiang Province,2021.Methods In 2021,stool samples from diarrhea patients in sentinel hospitals and food samples collected from markets were conducted for the isolation of Escherichia coli,and virulence genes were detected by multiplex quantitative PCR.Drug resistance detection and molecular typing of 104 strains were performed by pulsed field gel electrophoresis.Results The detection rate of concentrated Escherichia coli(EAEC)was the highest in case sources(60.66%),and also the highest in food sources(92.86%).The number of patients caused by DEC was the highest in the age group of 20 to 39 years old,and the peak of the incidence was from June to August.The highest drug resistance rate was observed in ampicillin(63.46%),followed by tetracycline(62.50%)and nalidixic acid(57.69%).After Xba I enzyme digestion,EAEC and ETEC were respectively clustered.The similarity of EAEC and ETEC were respectively 41.7%-100.0%and 40.7%-100.0%.Conclusion In 2021,most of the diarrhegenic Escherichia coli detected in Huzhou City was EAEC,with the highest resistance to ampicillin.A local PFGE molecular typing database was established to provide data support for DEC prevention and control.