Point-prevalence surveys for infection or colonization with methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae (CREs), and for Clostridium difficile infection (CDI) were conducted in Canadian hospitals in 2010 and 2012 to better understanding changes in the epidemiology of antimicrobial-resistant organisms (AROs), which is crucial for public health and care management.

A third survey of the same AROs in adult inpatients in Canadian hospitals with ≥50 beds was performed in February 2016. Data on participating hospitals and patient cases were obtained using standard criteria and case definitions. Associations between ARO prevalence and institutional characteristics were assessed using logistic regression models.

In total, 160 hospitals from 9 of the 10 provinces with 35,018 adult inpatients participated in the survey. Median prevalence per 100 inpatients was 4.1 for MRSA, 0.8 for VRE, 1.1 for CDI, 0.8 for ESBLs, and 0 for CREs. No significant change occurred compared to 2012. CREs were reported from 24 hospitals (15%) in 2016 compared to 10 hospitals (7%) in 2012. Routine universal or targeted admission screening for VRE decreased from 94% in 2010 to 74% in 2016. Targeted screening for MRSA on admission was associated with a lower prevalence of MRSA infection. Large hospitals (>500 beds) had higher prevalences of CDI.

This survey provides national prevalence rates for AROs in Canadian hospitals. Changes in infection control and prevention policies might lead to changes in the epidemiology of AROs and our capacity to detect them.

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.