Contamination of Clinical White Coats with Potential Pathogens and their Antibiotic Resistant Phenotypes Among a Group of Sri Lankan Medical Students

Background: Clinical white coats worn by the medical students can be contaminated at hospitals and act as a potential reservoir for pathogens including antibiotic-resistant bacteria. This study aimed to identify the contamination rates of clinical white coats worn by medical students with selected potential pathogens and their antibiotic resistant phenotypes. Methods: A cross-sectional study was done among 151 4th year medical students of Faculty of Medicine, University of Peradeniya, Sri Lanka in September 2020. The participants belonged to two batches undergoing clinical training at two settings. Swabs from pockets and sleeves of the clinical white coats were taken. Potential pathogens and their resistant phenotypes were identified with routine tests. Results: Fifty-three participants (35.1%) had coats contaminated with Staphylococcus aureus; 15 (9.9%) had coats contaminated with Methicillin-Resistant S.aureus (MRSA).  One Enterobacterales (0.7%) was an AmpC producer.  Enterococcus species were isolated from 19 (12.6%) coats and 2 (1.3%) had coats contaminated with vancomycin resistant enterococci.  Molecular testing on the MRSA isolates identified that 5(20%) of the MRSA isolates were PVL positive while all were mecA positive. Sex, type of clinical appointment, and frequency of washing white coats were not associated with contamination. The “batch” was significantly associated with contamination with S.aureus and Enterococcus species.  Conclusions: We found that clinical white coats worn by medical students recruited for the study were contaminated with S.aureus, MRSA and Enterococcus species. There was a notably high-rate of contamination with S. aureus.  All MRSA isolates were mecA positive while the rate of PVL positivity was low.