2013-2017年西安市食物中毒中金黄色葡萄球菌分型分析

  目的  了解2013-2017年西安市食物中毒中分离的金黄色葡萄球菌（staphylococcus aureus，S.aureus）分子流行特点。  方法  通过脉冲场凝胶电泳（pulsed field gel electrophoresis，PFGE）、多位点序列分型（multilocus sequence typing，MLST）和spa分型方法对八起食物中毒标本的26株金黄色葡萄球菌进行分子分型，运用聚合酶链式反应（polymerase chain reaction，PCR）检测相关肠毒素基因。  结果  26株S.aureus PFGE可分为7种型别（A-G）；MLST可分为3种序列型（ST6，ST5和ST59）。其中，ST6占65.38%，为主要型别；spa可分为4种型别（t437，t701，t11363和t5923），优势型别为t701，占65.38%。肠毒素基因检测中，sea基因占76.92%（20/26）；sed-seg基因占23.08%（6/26）；其它肠毒素基因未检出。  结论  2013-2017年西安市食物中毒标本中分离培养的S.aureus的主要流行型别为ST6-t701-sea，并首次检出含有seg新型肠毒素基因。PFGE、MLST和spa分型三种方法相结合全面的了解菌株的分子流行特点。

Molecular Epidemiological Characteristics of Staphylococcus aureus Strains Associated with Food Poisoning in Xi'an from 2013 to 2017

  Objective  To understand the molecular epidemiological characteristics of staphylococcus aureus(S.aureus), which was isolated from food poisoning in Xian between 2013 and 2017.  Methods  A total of 26 S.aureusisolates from 8 outbreaks were analyzed by using pulsed field gel electrophoresis(PFGE), multilocus sequence typing(MLST) and spa typing. polymerase chain reaction(PCR) analysis was used to analyze the staphylococcal enterotoxin genes sea to sei.  Results  26 strains of S.aureus were divided into 7 types of A-G by PFGE; They were divided into 3 types by MSLT, ST6 accounted for 65.38% which was the main type; They were Divided into 4 types by spa typing, t701 accounted for 65.38% which is the dominant type. The sea accounted for 76.92% (20/26) in the enterotoxin gene testing; sed-seg accounted for 23.08% (6/26); other enterotoxin genes were not detected.  Conclusion  The predominant type of S.aureus isolated from food poisoning in Xi'an was ST6-t701-seaprofile from 2013 to 2017. The first detection of the new enterotoxin gene seg, PFGE, MLST and spa typing were combined to fully understand the molecular epidemic characteristics of strains.