| Summary: | <i>Staphylococcus aureus</i> is one of the major foodborne pathogens and can cause serious foodborne illness in humans by foods contaminated with <i>S. aureus</i> enterotoxins. In recent years, livestock-associated <i>S. aureus</i> has been a major public health concern for humans and has emerged in various countries globally. China is one of the largest producers of pigs and pork in the world. However, there are few studies on the detailed genotypic and pathogenic characterization of pork-associated <i>S. aureus</i> in China. In this study, the prevalence, antimicrobial resistance, and genotypic characteristics of <i>S. aureus</i> in raw pork in Wuhan, China, were investigated through multilocus sequence typing (MLST), staphylococcal protein A gene (<i>spa</i>) typing, and whole-genome sequencing analysis. A total of 518 <i>S. aureus</i> isolates (16.9%) were isolated from 3067 retail and wholesale pork samples. The prevalence of <i>S. aureus</i> in retail pork (22.7%) was significantly higher than in wholesale pork (15.1%), while the proportion of multidrug-resistant (MDR) isolates in wholesale pork (12.9%) was significantly higher than in retail pork (6.2%). Among the isolates, 10.8% were resistant to three or more antibiotics, with higher rates of resistance to penicillin (88.8%) and erythromycin (58.1%). A total of 28 sequence types (STs) were identified in the 518 isolates, and the predominant type was ST7 (57.5%), followed by ST5 (9.1%). In addition, based on the whole-genome sequences of 39 representative strains, 17 <i>spa</i> types were identified among the isolates, of which t899, t091, and t437 were the most common. Furthermore, 19 staphylococcal enterotoxin (SE) and SE-like (SEl) toxin genes were detected in the isolates, of which <i>selw</i> was the most common type (100%), followed by <i>sei</i>, <i>sem</i>, <i>seo</i>, <i>seu</i>, and <i>selv</i> (46.2%); <i>sey</i> (35.9%); and <i>sea</i>, <i>seg</i>, and <i>sen</i> (33.3%). This study found for the first time that ST7-t091-<i>selw</i> and ST9-t899-SCCmecXII-<i>selw</i> were the predominant genotypes of <i>S. aureus</i> in pork in China, which indicated the spreading of <i>S. aureus</i> with multiple virulence factors, especially with new SE/SEl types in pigs and pork, is a serious new challenge for food safety. Good hygiene and good production practices to prevent interspecies transmission and cross-contamination of <i>S. aureus</i> in the pig–pork chain are of great significance to public health.
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