Department of Respiratory Medicine, The First People's Hospital of Yunnan province, Kunming, 650022, China.
The Affiliated Hospital of Kunming University of Science and Technology, Kunming, Yunnan, China.
BMC Microbiol. 2018 Aug 29;18(1):91. doi: 10.1186/s12866-018-1239-z.
Staphylococcal food poisoning (SFP) is one of the most common food-borne diseases in the world. Pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and spa typing methods were used to characterize Staphylococcus aureus isolates from food surveillance during 2013-2015 in southwest China, and Staphylococcal cassette chromosome mec (SCCmec) typing was used for methicillin-resistant S. aureus (MRSA). Isolates were also examined for their antibiotic resistance and carriage of virulence genes.
Isolation rate of S. aureus was 2.60% during the three years' surveillance and 29.50% of them were MRSA. All the S. aureus had hla genes (100%), 14.34% of the strains had tst, and 16.73% had PVL. 163 PFGE-SmaI patterns, 41 ST types and 36 spa types were obtained for all the S. aureus. Among them, ST6-t701 (13.15%), ST7-t091 (12.75%), ST59-t437 (9.96%) and ST5-t002 (7.57%) were the prevalent genotypes. Most of MRSA in this study belonged to SCCmec IV and V, accounted for 74.32% and 20.27% respectively. ST6-SCCmec IV-t701 (36.50%) was the most prevalent clone among isolates from food, followed by ST59-SCCmec V-t437 (20.30%), ST5-SCCmec IV-t002 (12.20%) and ST59-SCCmec IV-t437 (12.20%). Some strains had the identical PFGE patterns, ST and spa types with isolates from patients.
S. aureus isolated from food in southwest China displayed heterogeneity. Isolates had the same genotype profiles with isolates from patients, indicating high homology.
葡萄球菌食物中毒（SFP）是世界上最常见的食源性疾病之一。本研究采用脉冲场凝胶电泳（PFGE）、多位点序列分型（MLST）和 spa 分型方法，对 2013-2015 年中国西南地区食品监测中分离的金黄色葡萄球菌进行了特征分析，并采用葡萄球菌盒式染色体 mec（SCCmec）分型方法对耐甲氧西林金黄色葡萄球菌（MRSA）进行了分型。还检测了分离株的抗生素耐药性和携带毒力基因情况。
三年监测中共分离出金黄色葡萄球菌 2.60%，其中耐甲氧西林金黄色葡萄球菌占 29.50%。所有金黄色葡萄球菌均携带 hla 基因（100%），14.34%的菌株携带 tst 基因，16.73%的菌株携带 PVL 基因。对所有金黄色葡萄球菌进行 PFGE-SmaI 酶切后共得到 163 种谱型、41 种 ST 型和 36 种 spa 型。其中，ST6-t701（13.15%）、ST7-t091（12.75%）、ST59-t437（9.96%）和 ST5-t002（7.57%）是主要流行基因型。本研究中的大部分耐甲氧西林金黄色葡萄球菌属于 SCCmec IV 和 V 型，分别占 74.32%和 20.27%。食品分离株中最常见的克隆株为 ST6-SCCmec IV-t701（36.50%），其次为 ST59-SCCmec V-t437（20.30%）、ST5-SCCmec IV-t002（12.20%）和 ST59-SCCmec IV-t437（12.20%）。部分菌株与患者分离株具有相同的 PFGE 图谱、ST 和 spa 型。
中国西南地区食品中分离的金黄色葡萄球菌表现出异质性。分离株与患者分离株的基因型谱相同，表明同源性较高。
