MRSA carriage rate among dental healthcare personnel: amulticentric cross-sectional study

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) represents a significant global healthcare challenge, yet its prevalence among dental personnel remains poorly understood. Objective: The aim of this study was to determine the carriage rate and related risk factors of MRSA among Colombian oral healthcare providers. Materials and Method: A multicenter descriptive cross-sectional study was conducted. Nasal swabs were obtained from 457 randomly selected healthcare professionals from dental services across eight cities in Colombia, using proportional stratified sampling and snowball sampling in 29% of the cases. Inclusion criteria were being a full time worker in a dentistry setting, and being healthy with no upper respiratory tract infection, fever, or use of antimicrobial therapy in the previous three months. Gram staining, catalase and coagulase tests were used to identify S. aureus colonies. The methicillin-resistant phenotype was detected using the Kirby-Bauer disc method. The virulence factor encoding genes mecA and Panton Valentine Leukocidine (PVL) were detected by polymerase chain reaction (PCR). Results: Overall prevalence of MRSA was 4.4% [95% confidence interval (CI): 2.5% – 6.2%], determined using mecA gene detection. Women carried 75% of the MRSA strains, and dentists accounted for 60%. Carrier rates were 4.03% [95% CI: 1.8% - 6.2%] for dentists, and 5.03% [95% CI: 1.6% - 8.4%] for other personnel. These rates did not differ significantly from each other (Fisher’s exact test, p=0.67). A personal history of hospitalization over the previous year was identified as a predisposing factor for the host (p=0.033). Conclusion: This multicenter study reveals a 4.4% MRSA carriage rate among Colombian dental healthcare providers. MRSA-carrying dental healthcare workers did not appear to have risk factors associated with professional activity.