浙江省肠出血性大肠杆菌O_(157)∶H_7动物宿主带菌情况调查

Research of Escherichia Coli O_(157):H_7 among Host Animals in Zhejiang Province

目的了解浙江省肠出血性大肠杆菌O157∶H7在动物宿主中的带菌情况。方法采集浙江省2006-2008年监测点的动物粪便进行病原菌培养和毒力基因及耐药性检测。结果共采集动物粪便3915份,检出肠出血性大肠杆菌O157∶H7阳性20份,带菌率为0.51%,其中以羊和牛的带菌率最高,分别为1.46%和1.43%,散养动物带菌率高于圈养动物(χ2=5.771,P=0.016)。阳性菌株stx2、hly和eaeA3种毒力基因均呈阳性,stxl均呈阴性。对红霉素和利福平耐药,耐药率达90%以上,对其他受试抗生素敏感。结论浙江省动物宿主有一定的带菌率,且菌株具有毒力基因,散养动物的带菌率高于圈养动物,应进一步加强监测,防止O157∶H7引起人群的爆发流行。

Objective To explore the distribution of Escherichia coli O157：H7 in host animals in Zhejiang province.Methods Feces samples of different animals were collected in three surveillance spots to culture for O157：H7 as well as detection of virulence genes and anti-microbial susceptibility tests of the strain.Chi-square test was used to analyze the carrier rate of O157：H7 in host animals.Results Twenty strains of O157：H7 were separated from 3915 feces of different animals with a overall positive rate 0.51%.The positive rates of sheep and cattle were 1.46% and 1.43% respectively,which were obviously higher than that of other animals.All of the strains of O157：H7 carried stx2,hly and eaeA simultaneously and 20 strains were resistant to erythromycin（95%）and rifampicin（100%）with susceptibility to other tested antibiotics.The positive rate of scattered-feeding animals was higher than of the captive animals（χ^2=5.771,P=0.016）. Conclusion Escherichia coli O157：H7 carrying virulence genes was detected in host animals in Zhejiang province and the positive rate of scattered-feeding animals was higher than of the captive animals.It suggests that the surveillance for O157：H7 should be reinforced in order to prevent its outbreak and popularity in people.