上海市浦东新区肠出血性大肠埃希菌O157：H7的监测研究

Surveillance on Escherichia coli O157:H7 in Shanghai Pudong New Area

目的了解上海浦东新区腹泻病人、宿主动物肠出血性大肠埃希杆菌(E.coli)O157:H7携带情况以及市售食品的污染状况,为疾病防治工作提供决策依据。方法于2003～2006年的5～10月,在设置的监测点与超市采集家禽和腹泻病人粪便及禽畜肉制品;应用免疫磁珠富集,山梨醇麦康凯平板和Chromager O157显色平板分离培养E.coliO157:H7,生化和血清学反应进行鉴定。结果E.coliO157:H7阳性率分别为:腹泻病人粪便0.24%,鸡粪2.95%,鸭粪3.83%,家畜肉15.05%,家禽肉2.25%。检出的67株E.coliO157:H7中,仅1株来自腹泻病人的E.coliO157:H7具有毒力基因。结论浦东新区腹泻病人、宿主动物及其肉类食品中存在E.coliO157:H7感染或污染,存在E.coliO157:H7感染流行的潜在危险。

Objective To investigate the occurrence of Escherichia coli O157∶H7 in diarrhea patients and host animals and the status of contamination in commercial foods in Shanghai Pudong New Area so as to provide scientific basis.Methods The immunomagnetic separation method in combination with the E.coli O157 ∶H7 chromogenic media,sorbitol MacConKey agar and serological biochemical tests were used to assess the prevalence of E.coli O157 ∶H7 in the fecal samples of the fowls,stools of diarrhea patients and meat wares of livestock and poultry collected from the monitoring sites and supermarkets in 5-10 months during years 2003-2006.Results The proportion of culture-positive for E.coli O157∶H7 in fecal samples of chicken and duck was 2.95% and 3.83%,respectively,while the rate in diarrhea patients was 0.24%.The pathogen was also detected in meat wares,15.05% of the livestock and 2.25% of the poultry.No virulence gene was observed in 66 strains of E.coli O157∶H7 except for one strain from a stool sample of diarrhea patient.Conclusion The occurrence of E.coli O157∶H7 in diarrhea patients,host animals and meat wares observed in Pudong New Area indicated a potential outbreak risk of this pathogen.