Aim: To know the prevalence of S.aureus and methicillin resistant S.aureus (MRSA) nasal carriage in medical students in different phases of medical education and to evaluate cefoxitin and oxacillin disc diffusion methods to detect methicillin resistance in nasal S.aureus isolates.

Materials and methods: The study was conducted on 104 medical students. Samples were collected from anterior nares using sterile cotton swab soaked in sterile saline and processed immediately. S. aureus isolates were identified by standard microbiological techniques. Cefoxitin and oxacillin disc diffusion tests were done by Kirby-Bauer method according to CLSI 2011 guidelines to detect MRSA.

Results: Over all S.aureus and MRSA nasal carriage was seen in 34.61% and 11.53% medical students. MRSA carriage was seen in 21.42% interns where as less than 4% MRSA carriage was seen in I and II phase students. Cefoxitin disc detected 12 and oxacillin disc detected 11 methicillin resistant S.aureus isolates.

Conclusions: Nasal carriage rate of MRSA was high among students exposed to patients and hospital environment. Medical students can be a potential source of nosocomial pathogens like MRSA. Cefoxitin disc diffusion was superior to oxacillin disc diffusion method in detecting MRSA. Continuous surveillance, decolonization of carriers and improvement in hygiene standards in hospitals should be adopted to break the transmission of MRSA.