Infection control practices related to Methicillin resistant S. Aureus in a national sample of acute care hospitals

Background: Methicillin resistant Staphylococcus aureus (MRSA) is an important cause of healthcare-associated infections (HAI). The purpose of this analysis was to identify infection control practices used by hospitals to prevent MRSA and structural characteristics associated with the presence of these practices.

Methods: A cross-sectional survey of 441 hospitals participating in the National Healthcare Safety Network was conducted. Descriptive statistics were utilized to describe the presence of practices. Associations were identified using Fisher's exact tests; those found to be significant (p-value=0.15) were analyzed with multivariate logistic regressions.

Results: A total of 264 hospitals provided data (response rate of 60%). More than half of the hospitals monitored MRSA rates (58.7%, n=155). The majority reported specific activities to decrease MRSA rates (95.4%, n=248), including patient isolation (92.3%, n=240), active surveillance (56.2%, n=146) and antibiotic restriction (40.8%, n=106). MRSA selective agar was the most frequently used method for active surveillance tests (30%, n=78), followed by PCR (21.2%, n=55) and standard culture (18.1%, n=47). In multivariate analysis, hospitals located in states with mandatory reporting of HAI and teaching hospitals were more likely to report active surveillance for MRSA (OR=2.0, 95% CI=1.2-3.5 and OR=2.7, 95% CI=1.6-4.8, respectively). Total hours of infection control staffing per week was a significant predictor of using antibiotic restriction to control MRSA (OR=1.005, 95%CI=1.001-1.009), after adjusting for teaching status.

Conclusion: Most hospitals are involved in activities to control MRSA, although there is considerable variation in measures employed. Teaching hospitals and those with mandatory reporting were significantly more likely to report active surveillance.