Objective To examine antimicrobial resistance and enterotoxigenicity of foodborne Staphylococcus aureus ( S. aureus) isolates in 29 provincial regions of China in 2017.
Methods Totally, 397 foodborne S. aureus isolates were collected in 29 provincial regions of China in 2017 and antimicrobial susceptibility, enterotoxin genes, and toxigenic capability of all isolates were tested.
Results In total, 96.5% (383/397) of the S. aureus isolates exhibited different resistant level to 13 antimicrobials tested. The resistance rate to penicillin (PEN) was the highest (94.7%). Moreover, 30.2% (120/397) were identified as multi-drug resistant (MDR) strains. Isolates from rice and flour products showed the most MDR, and the MDR rates were 7.4% (34/91) and 37.3% (19/51), respectively. A total of 72 drug resistant spectrums were identified from all 397 isolates. Furthermore, 20 virulence genes were detected in 284 isolates. The typical SEs genes of sea, seb, sec and sed were detected in 82 strains (20.7%, 82/397) with sea (14.9%) and sec (5.0%) as the most frequently detected. More than 90% of the sea to sed carrying isolates were confirmed with the capacity to produce enterotoxins.
Conclusion An overall high level antimicrobial resistance was found among foodborne S. aureus isolates in China in 2017, so was the MDR condition, especially for strains recovered from some foods. Virulence genes could be frequently detected in foodborne S. aureus isolates, most of which could produce enterotoxins.
【摘 要】 目的 了解 2017 年中国食源性金黄色葡萄球菌（金葡菌）耐药和肠毒素特征。 方法 2017 年收集全国 29 个省市食源性金葡菌 397 株，并测定其抗生素耐药性、肠毒素基因和产肠毒素情况。 结果 96.5 %（383/397）金葡菌对受试的 13 种抗生素呈不同程度耐药，其中青霉素（PEN）耐药率最高（94.7 %）；30.2 %（120/397）金葡菌为多重耐药，米面制品和面包来源金葡菌多重耐药率最高，分别为 37.4 %和 37.3 %；共存在 72 种耐药谱。284 株金葡菌检出了 20 种肠毒素基因，其中 sea、 seb、 sec和 sed等常见肠毒素基因检出 82 株（20.7 %，82/397），其中 sea（14.9 %）基因检出率明显高于 seb～ sed基因（ χ2 = 74.534， P < 0.05），90 %以上的菌株均能产生 SE-A～SE-D 肠毒素。 结论 2017 年中国 29 个省市食源性金葡菌耐药水平较高，多重耐药现象严重，且同时携带多种肠毒素基因并能产肠毒素。