对流行地区的E.coli O157∶H7病原学分析及研究

Aetiological Analysis and Study on E.coli O157∶H7 in Epidemic Area

目的 对流行地区O15 7∶H7进行病原学分析。方法 PCR方法对O15 7∶H7菌株毒力基因谱检测比较 ,同时用PFGE和RAPD方法对O15 7∶H7菌株的同源性分析比较。结果 流行地区分离的O15 7∶H7菌株 ,10 0 %携带Hly、eaeA基因 ,95 35 %携带SLT2 基因 ,11 6 3%携带SLT1基因。PFGE图谱表明流行地区分离的O15 7∶H7菌株与日本分离的O15 7∶H7菌株有明显差异 ,为不相关菌株 ;与国内标准菌株 882 36 4为近似型 (相似 ,但不相同 )。流行地区病人分离菌株与外环境家畜家禽类便及昆虫肠道分离菌株的PFGE图谱完全相同。结论 携带O15 7∶H7菌株的家畜家禽可能是导致疫情发生的传染源。PFGE用于O15 7∶H7病原学分析 ,对流行病学研究有重要意义 ,但不适宜基层。RAPD方法用于O15 7∶H7病原学分析 ,技术简便、省时。

Objective To analyze E.coli O157∶H7 of epidemic area.Methods To compare the virulence gene spectrum of E.coli O157∶H7 strains by PCR and analyze the homology of E.coli O157∶H7 strains by PFGE and RAPD.Results In all E.coli O157∶H7 strains isolated from epidemic area,100% possess Hly and eaeA gene,95 35% possess SLT2 gene,11 63% possess SLT1 gene.The PFGE spectrum shows that the strains isolated from epidemic area are distinctively different from the strains isolated from Japan,and they are similar to but not same with the standard strain 882364.The PFGE spectrum of strains isolated from epidemic area patients are same with that of strains isolated from excrement of prutries and domestic animals and inscet intestine.Conclusion Poultries and domestic animals which carry E.coli O157∶H7 could be source of infection.PFGE could be used to analyze E.coli O157∶H7 and is important in epidemicology study,but is not fit to be used in grass roots unit.Analyzing E.coli O157∶H7 by RAPD is convenient and time saving.