Background and purpose: Methicillin-resistant Staphylococcus aureus (MRSA) is one ofthe most common causes of serious nosocomial infections. The important way of spreadingthis organism in the hospital is through health care providers who are asymptomatic carriers.Strains that have the ability to toxic shock syndrome toxin-۱ (TSST-۱), and pantone-valentineleucocidin (PVL) genes can cause invasive diseases. The aim of this study was to determinethe frequency of
asymptomatic carriers of MRSA, the pattern of antibiotic resistance, and thevirulence genes.Method and material: In this cross-sectional, descriptive study, we evaluate ۱۲۰ Healthcareproviders working in the intensive care unit (ICU) of Ganjovian Hospital- Dezful. Nasal swabsamples were cultured on mannitol salt agar and blood agar. The resistance pattern of isolatedS. aureus bacteria was done by disk diffusion and microbroth dilution methods for differentantibiotics. Polymerase chain reaction (PCR) was used to check the presence of mec gene andvirulence genes alpha-toxin (Hla), TSST-۱, and PVL.Results: Fifteen samples (۱۲.۵%) were carriers for S. aureus, of which ۴۰% (n=۶) were maleand ۴۰% (n=۶) had a history of taking antibiotics in the past ۳ months. ۲۶.۶% (n=۴) strainswere MRSA. In total, antibiotic resistance pattern to erythromycin was ۷۳%, clindamycin۶۶.۶%, cefoxitin ۲۶.۶%, penicillin ۱۰۰%, ciprofloxacin ۴۶.۶%, levofloxacin ۵۳.۳%,gentamicin and cotrimoxazole ۶.۶%. All strains were sensitive to rifampin, linezolid,vancomycin, daptomycin and teicoplanin. All four MRSA strains had the mec gene. Hla genewas detect in ۶۶.۶% of S. aureus strains, but TSST-۱ and PVL genes were not observed inany of the isolates.Conclusion: According to the frequency obtained in this study and previousrecommendations, we suggest that staff who work in the ICU should be serially evaluatedand S. aureus carriers must be treated to eliminate the carrier. Also, adherence of standardprecautions for exposing to ICU patients is necessary.