Prevalence and Risk Factors for Methicillin-Resistant Staphylococcus aureus Carriage among Healthcare Workers in a Tertiary Health Facility in Nigeria

Background: Methicillin-resistant Staphylococcus aureus (MRSA) colonized healthcare workers (HCWs) constitute massive threat to the well-being of hospitalized patients due to their ability to transmit this multidrug-resistant (MDR) bacteria strain in hospital settings.

Aim: To determine the prevalence of MRSA carriage/colonization among HCWs, to identify risk-factors associated with colonization/carriage, and to determine the antibiotic resistance pattern of isolates.

Study Design: A cross-sectional study.

Materials and Methods: A total of 333 randomly selected consenting HCWs from most hospital care units were studied. Data on demographic characteristics and infection control practices were obtained from participants with the aid of questionnaire. Swabs of the anterior nares and hands of participants were cultured on oxacillin-containing mannitol salt agar (MSA), S. aureus was identified using convectional criteria and MRSA was identified by cefoxitin disc diffusion technique. Antibiotic susceptibility testing was carried out on all isolated MRSA.

Results: The carriage rate of MRSA was high (21.3%). Isolation was significantly higher among; males compared to females (P=.035), staff of critical care units compared to other care units (P=.049), among doctors and nurses compared to other HCWs (P=.0031). Poor handwashing practices (P<.001), presence of wound or skin infection (P<.001) and recent antibiotic use (P=.006) were associated with higher isolation rate. Isolation rate was higher from the nose (15.0%) than from the hands (6.3%). Isolates demonstrated low resistance to clindamycin (16.9%) and ciprofloxacin (16.9%). No isolate was resistant to vancomycin.

Conclusion: In this study; colonization of HCWs by MRSA was high, a male doctor or nurse from critical care unit, with poor handwashing practices, wound or skin infection, and recent antibiotic use had a higher risk of MRSA carriage/colonization. No MRSA isolated was resistant to vancomycin. Improved infection control policies and practices are needed to curtail this trend in hospital settings.