深圳市食物中毒来源金黄色葡萄球菌的分子流行病学分析

Molecular epidemiological survey of Staphylococcus aureus from food poisoning samples in Shenzhen city

目的建立金黄色葡萄球菌(金葡菌)的分子分型技术,研究深圳市食物中毒来源金葡菌的分子流行病学特征。方法对食物中毒事件中食物链的不同环节均采集标本,进行金葡菌分离培养。对所分离菌株同时应用SPA分型及PFGE技术作分子流行病学分析。结果 136起疑似食物中毒事件中有12起能够从食物链不同环节分离到金葡菌,共59株。PFGE将59株金葡菌分为15个型别,在10起食物中毒事件的不同环节中分析到PFGE型别一致的菌株,分辨系数为0.87。SPA分型将59株金葡菌分为10个型别,在12起食物中毒事件中不同环节样品中分析到SPA型别一致的菌株,分辨系数为0.85。结论 PFGE的分辨力高于SPA分型;通过结合流行病学资料分析,12起食物中毒事件中有6起能够通过分子分型方法准确溯源。

Objective To establish different molecular method for genotyping Staphylococcus aureus. Methods Thespecimens were extracted from different segments of the food chain in the suspected food- posoning cases for isolation anculture of the Staphylococcus aureus. The isolated bacteria strains with the SPA and PFGE genotyping technique wereepidemiologically analyzed. Results Fifty-nine Staphylococcus aureus strains were isolated from specimens from 12 casesof the 159 food-poisoning events. The 59 strains were divided into 15 genotypes by PFGE,and it could get the same strains asPFGE type from different segments in the 10 food poisoning cases, resolution ratio is 0.87. 59 strains were divided into 10 genotypes by SPA,and it can get the same strains as SPA type from different segments in the 12 food poisoning cases, resolutionratio is 0.85. Conclusion Base on the results of molecular typing and epidemic data, we consider there are 6 cases of food-poisoning diseases are effective in tracing infection sources of Staphylococcus aureu,PFGE＇s resolution is higher than SPA type.