Distribution of 20 enterotoxin and enterotoxin-like genes in Staphylococcus aureus strains isolated from healthy carriers in Beijing

Objective To investigate the distribution of 20 enterotoxin (SE) or enterotoxin-like (SEl) genes in Staphylococcus (S.) aureus strains isolated from healthy carriers. Methods A total of 100 S. aureus strains were collected from healthy carriers in Chaoyang district of Beijing to detect 20 SE and SEl genes with PCR. Spa typing and multiple locus sequence typing (MLST) were performed. Results Among the 100 S. aureus strains, 64 carried one or more SE or SEl genes. The most common genes were sea, seg, selm, seln, sell and seb. The most common enterotoxin were sea and selp, which accounted for 10% respectively. Enterotoxin sea was mainly distributed in ST6 (29.4%, 5/17) and ST401 strains (29.4%, 5/17), while 50% of selp carrying strains belonged to spa t796. Conclusion The high carriage of enterotoxin in S. aureus strains isolated from healthy carriers might be a risk factor for food poisoning.