Prevalence of Colonization and Infection with Methicillin-ResistantStaphylococcus aureusand Vancomycin-ResistantEnterococcusand ofClostridium difficileInfection in Canadian Hospitals

Abstract

To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Clostridium difficile infection (CDI) in Canadian hospitals. National point prevalence survey in November 2010. Canadian acute care hospitals with at least 50 beds. Adult inpatients colonized or infected with MRSA or VRE or with CDI. The prevalence (per 100 inpatients) of MRSA, VRE, and CDI was determined. Associations between prevalence and institutional characteristics and infection control policies were evaluated. One hundred seventy-six hospitals (65% of those eligible) participated. The median (range) prevalence rates for MRSA and VRE colonization or infection and CDI were 4.2% (0%-22.1%), 0.5% (0%-13.1%), and 0.9% (0%-8.6%), respectively. Median MRSA and VRE infection rates were low (0.3% and 0%, respectively). MRSA, VRE, and CDI were thought to have been healthcare associated in 79%, 96%, and 84% of cases, respectively. In multivariable analysis, routine use of a private room for colonized/infected patients was associated with lower median MRSA infection rate (prevalence ratio [PR], 0.44 [95% confidence interval (CI), 0.22-0.88]) and VRE prevalence (PR, 0.26 [95% CI, 0.12-0.57]). Lower VRE rates were also associated with enhanced environmental cleaning (PR, 0.52 [95% CI, 0.36-0.75]). Higher bed occupancy rates were associated with higher rates of CDI (PR, 1.02 [95% CI, 1.01-1.03]). These data provide the first national prevalence estimates for MRSA, VRE, and CDI in Canadian hospitals. Certain infection prevention and control policies were found to be associated with prevalence and deserve further investigation.