Prevalence, antimicrobial resistance, and enterotoxin gene profiles of Staphylococcus aureus isolated from mobile phones of the food vendors in Phayao province, Thailand

BACKGROUND: Mobile phones are widely used and may cause bacterial pathogens to spread among various professionals. Staphylococcus aureus from the mobile phones can contaminate the hands of food vendors and food during the cooking or packaging process. This research aimed to determine the prevalence, enterotoxin genes, and antimicrobial resistance (AMR) profiles of S. aureus contaminating the vendors’ mobile phones. METHODS: In this study, 266 mobile phone samples were randomly collected from food vendors selling food on walking streets (n = 139) and in food centers (n = 127) in Phayao province. All samples were identified as S. aureus by the conventional culture method and confirmed species-specific gene by polymerase chain reaction (PCR). Then, all identified S. aureus isolates were tested for antimicrobial susceptibility by broth microdilution method and for the presence of staphylococcal enterotoxin (SE) genes by PCR. RESULTS: The results showed that 12.8% of the mobile phones collected were contaminated with S. aureus. Of 49 S. aureus isolates obtained, 30 (61.2%) were positive for SE genes. The most common SE gene was sea followed by sec, seb, sem, seq, and sel. Moreover, S. aureus was most frequently resistant to penicillin, followed by chloramphenicol and tetracycline, erythromycin, clindamycin, and gentamicin. Methicillin-resistant S. aureus (MRSA), vancomycin-resistant S. aureus (VRSA), and multidrug-resistant (MDR) strains were also detected. CONCLUSIONS: This study showed that mobile phones were an intermediate surface for the transmission of S. aureus, including MDR variants. It indicates that hand hygiene and the decontamination of mobile phones are essential to prevent cross-contamination of S. aureus in food settings.