2018—2020年湖州市腹泻人群致泻大肠埃希菌流行特征及病原分析

目的 了解湖州市腹泻人群中致泻大肠埃希菌(DEC)的感染状况、主要毒力基因以及耐药情况。方法 对2018—2020年各哨点医院腹泻患者粪便标本进行分离,采用多重荧光定量聚合酶链式反应(PCR)法对DEC分离株进行毒力基因检测,用微量肉汤稀释法进行药敏试验。结果 共检出DEC阳性病例293例,分离菌株294株。肠集聚性大肠埃希菌(EAEC)占55.4%(163/294),肠产毒性大肠埃希氏菌(ETEC)占29.6%(87/294),肠致病性大肠埃希氏菌(EPEC)占11.2%(33/294),肠侵袭性大肠埃希氏菌(EIEC)占3.4%(10/294),肠出血性大肠埃希氏菌(EHEC)占0.3%(1/294)。随机选取117株DEC对氨苄西林、萘啶酸、氨苄西林-舒巴坦、四环素进行耐药性检测,耐药率分别为70.9%、60.7%、53.8%、51.3%。多重耐药率达到55.6%。对亚胺培南、头孢他啶、阿莫西林-克拉维酸、头孢西丁的敏感率为99.1%、92.3%、92.3%和91.5%。DEC引起的腹泻发病高峰在7—8月,20～39岁为主要感染人群。结论 湖州市腹泻人群感染DEC基因型别以EAEC和ETEC为主,存在多重抗生素耐药,病例分布呈现明显的季节性,感染人群以青壮年为主。

Epidemiologic characteristics and pathogen analysis of Diarrheagenic Escherichia coli in Huzhou, 2018-2020

Objective To investigate the infection status, main virulence genes and drug resistance of diarrheagenic Escherichia coli (DEC) in the diarrhea population in Huzhou, Zhejiang Province. Methods DECs were isolated from fecal specimens from patients with diarrhea in three sentinel hospitals from 2018 to 2020. All clinical isolates were then further identified using multiplex real-time fluorescence quantitative polymerase chain reaction (PCR). The microbroth dilution method was used for drug sensitivity testing. DECs were isolated from fecal specimens collected from 2018 to 2020 from patients with diarrhea in three sentinel hospitals. All clinical isolates were then further identified using multiplex real-time fluorescence quantitative PCR. The microbroth dilution method was used for drug sensitivity testing. Results A total of 293 DEC positive cases were detected, and 294 strains were isolated. Enteroaggregative Escherichia coli (EAEC) accounted for 55.4% (163/294), and Enterotoxigenic Escherichia coli (EPEC) accounted for 29.6% (87/294). Enteropathogenic Escherichia coli (EPEC) accounted for 11.2% (33/294), Enteropathogenic Escherichia coli (EPEC) accounted for 11.2% (33/294), Enteroinvasive Escherichia coli (EIEC) accounted for 3.4% (10/294) and Enterohemorrhagic Escherechia coli (EHEC) accounted for 0.3%(1/294). The antimicrobial resistance rates of 117 randomly selected strains to AMP ampicillin, NAL nalidixic acid, AMS ampicillin-Sulbactam and TET tetracyclin AMP, NAL, AMS and TET were 70.9%, 60.7%, 53.8% and 51.3%, respectively. The multidrug resistance rate reached 55.6%. The sensitivity rates to IMP imipenem, CAZ ceftazidime, AMC amoxicillin clavulanic acid and CFX cefoxitin IMP, CAZ, AMC and CFX were 99.1%, 92.3%, 92.3% and 91.5%. DEC cases had a peak in July to August, and the main infected population was between 20 and 39 years old. strains of DEC were randomly selected to AMP, NAL, AMS and TET were 70.9%, 60.7%, 53.8% and 51.3%, respectively. The multidrug resistance rate reached 55.6%. The sensitivity rates to IMP, CAZ, AMC, and CFX were 99.1%, 92.3%, 92.3% and 91.5%. DEC cases had a peak in July to August, and the main infected population is between 20 and 39 years old. Conclusion The DEC genotypes of the patients with diarrhea in Huzhou, Zhejiang Province were mainly EAEC and ETEC, with multiple antibiotic resistance. The distribution of cases was obviously seasonal, and the infected population was mainly young adults.