Abstract：Objective To perform enterotoxin gene detection, drug sensitivity test and molecular typing by pulsed-field gel electrophoresis (PFGE) on Staphylococcus aureus (S. aureus) isolates from different foods in Songjiang District of Shanghai from 2017 to 2021, and to understand the etiological characteristics of S. aureus. Methods Enterotoxin genes in S. aureus isolates were detected by PCR. Susceptibility test was performed using the microbroth dilution method recommended by Clinical and Laboratory Standards Institute. PFGE was used for genotyping. Results Enterotoxin genes were detected in 39 of 108 strains of foodborne S. aureus, and the detection rate was 36.1%, including sea (28.02%, 11/39), seb (41.0%, 16/39), sec (33.3%, 13/39), and sed (12.8%, 5/39). The results of drug sensitivity test showed that the drug resistance rates of ampicillin (83.3%), penicillin (80.6%), and erythromycin (42.6%) were the highest, whereas the drug resistance rates of vancomycin (100.0%), daptomycin (98.1%) and gentamicin (94.4%) were the lowest. There were 15 strains of methicillin-resistant S. aureus. 20 strains of S. aureus showed multiple drug resistance, among which one strain was the most resistant to six kinds of antibiotics. The results of PFGE molecular typing revealed that 11 of 108 S. aureus strains could not be typed, and the other 97 strains were divided into 19 clusters, including 77 types, showing diversity. Conclusion From 2017 to 2021, the high carrying rate of enterotoxin gene and multiple drug resistance of foodborne S. aureus in Songjiang District of Shanghai need to be paid attention to, and the monitoring of S. aureus in foods should be strengthened so as to provide a scientific basis for food safety risk assessment and prevention of foodborne diseases.
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2023, Vol. 30 
