金黄色葡萄球菌食品分离株肠毒素基因及耐药性研究

Study of enterotoxin gene and drug resistance in food borne Staphylococcus aureus

目的了解2015年2月-2017年9月上海市金黄色葡萄球菌食品分离株肠毒素基因分布规律及耐药情况。方法采用酶联免疫法(ELISA)检测金黄色葡萄球菌的5种毒力基因sea^see,同时用CLSI推荐的微量肉汤稀释法进行药敏试验,定量测定最低抑菌浓度(MIC)。结果 106株金黄色葡萄球菌食品分离株中有68株检出肠毒素基因,肠毒素基因携带率为64.2%,同时携带2种毒素基因的菌株占7.4%(5/68)。微量肉汤稀释法检出91株金黄色葡萄球菌耐药株,76.9%(70/91)为2重以上的多重耐药菌,呈现21种耐药表型谱,耐药性最强的菌株对6种抗生素产生耐药性。结论上海地区金黄色葡萄球菌食品分离株产肠毒素能力较强且多重耐药性严重,应加强食源性金黄色葡萄球菌的监测,为临床合理使用抗生素和开展食品安全风险评估提供科学依据。

Objective To investigate the distribution and drug resistance of enterotoxin gene in food borne Staphylococcus aureus in Shanghai from February 2015 to September 2017. Methods Five virulence genes（ sea-see） of Staphylococcus aureus were detected by enzyme-linked immunosorbent assay（ ELISA）,and susceptibility test was performed using the microbroth dilution method recommended by CLSI,and the minimum inhibitory concentration（ MIC） was conducted for quantitative detection.Results Enterotoxin gene was detected from sixty-eight strains of food borne Staphylococcus aureus from 106 strains,with the carrying rate of enterotoxin gene as 64. 2%,and the strains carrying the two toxin genes accounted for 7. 4%（ 5/68）. A total of91 resistant strains of Staphylococcus aureus were detected by broth dilution method,76. 9%（ 70/91） of them were multiple drug resistant bacteria,showing 21 kinds of resistant phenotype spectrum,and the most resistant strain was resistant to six antibiotics.Conclusion Food borne Staphylococcus aureus in Shanghai have strong ability of producing enterotoxin and the multiple drug resistance is strong. It showed that we should strengthen the monitoring of food borne Staphylococcus aureus,and provide scientific basis for clinical rational use of antibiotics and food safety risk assessment.