Frequency of Nasal Carriage of Staphylococcus aureus Among Healthcare Workers (HCWs) and Patients in Bandar Abbas, Southern Iran

Background: Staphylococcus aureus is a problematic infectious agent in hospitals as well as in the community. Nasal carriage of healthcare workers (HCWs) and sometimes patients are an important source for transmitting this bacterium to vulnerable individuals. Objectives: The present study aimed to investigate the frequency of nasal carriage of S. aureus and the antimicrobial susceptibility pattern of this organism isolated from HCWs and patients at Shahid Mohammadi Hospital in Bandar Abbas, South of Iran. Methods: This cross-sectional study was conducted from November 2017 to December 2018. A total of 400 nasal swabs were taken from HCWs and patients to investigate the presence of S. aureus. An antimicrobial susceptibility pattern was carried out using the disc diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Methicillin resistance was determined using cefoxitin disc diffusion and PCR for mecA gene. Agar dilution was performed to determine MIC of vancomycin and mupirocin. Results: Of 130 HCWs, 11 (8.5%) subjects were nasal carriers, of which 5 (45.5%) harbored methicillin-resistant Staphylococcus aureus (MRSA). Of 270 patients, 21 (7.8%) patients were nasal carriers, of whom 9 (42.9%) patients were MRSA carriers. Linezolid and vancomycin were the most effective agents, and 100% of isolates were susceptible to these agents. Furthermore, high-level mupirocin-resistant S. aureus (HLMuRSA) was observed in 6.3% of the isolates. Conclusions: Our findings demonstrate that the rate of nasal carriage among HCWs and patients was lower than global reports. However, the frequency of MRSA was comparable with previously reported ranges and was approximately high. Vancomycin and linezolid are the most effective antimicrobial agents. Appropriate decolonization is recommended for the control of transmission of MRSA to vulnerable individuals.