High Prevalence of Nasal carriage of Methicillin Resistant Coagulase Negative Staphylococci among Medical Students in a Tertiary Care Institution in North India

Abstract

Introduction: MBBS students during rotational clinical postings run the risk of being colonised by critical hospital
pathogens such as Methicillin-resistant staphylococci (MRSA and MRCoNS). Methods: This study was conducted on
150 undergraduate MBBS students from August to September 2018 to determine prevalence of nasal colonization rates of
MRSA /MRCoNS in them. One sterile cotton tipped swab per student was used to collect specimen from the anterior nares.
This was inoculated on 5 % Sheep Blood agar. Isolated suspected Staphylococci colonies were speciated and Methicillin
resistance was determined by disc diffusion tests as per standard protocols. Overall prevalence of MRCoNS (22%) among
students was significantly higher compared to MRSA(4%). MRCoNS colonisation was also significantly higher in clinic
going students. Conclusion: Compared to MRSA, little information is available on epidemiology of CoNS/MRCoNS
among healthcare workers as these bacteria are considered harmless commensals. Findings of this study suggest that
those involved in patient care including medical students may be carriers of MRCoNS similar to MRSA and could be
potential sources of infection to vulnerable patients.