Trends in health care-associated infections in acute care hospitals in Canada: an analysis of repeated point-prevalence surveys.

Background: Health care-associated infections are a common cause of patient morbidity and mortality. We sought to describe the trends in these infections in acute care hospitals, using data from 3 national point-prevalence surveys.

Methods: The Canadian Nosocomial Infection Surveillance Program (CNISP) conducted descriptive point-prevalence surveys to assess the burden of health care-associated infections on a single day in February of 2002, 2009 and 2017. Surveyed infections included urinary tract infection, pneumonia, infection, infection at surgical sites and bloodstream infections. We compared the prevalence of infection across the survey years and considered the contribution of antimicrobial-resistant organisms as a cause of these infections.

Results: We surveyed 28 of 33 (response rate 84.8%) CNISP hospitals (6747 patients) in 2002, 39 of 55 (response rate 71.0%) hospitals (8902 patients) in 2009 and 47 of 66 (response rate 71.2%) hospitals (9929 patients) in 2017. The prevalence of patients with at least 1 health care-associated infection increased from 9.9% in 2002 (95% confidence interval [CI] 8.4%-11.5%) to 11.3% in 2009 (95% CI 9.4%-13.5%), and then declined to 7.9% in 2017 (95% CI 6.8%-9.0%). In 2017, device-associated infections accounted for 35.6% of all health care-associated infections. Methicillin-resistant (MRSA) accounted for 3.9% of all organisms identified from 2002 to 2017; other antibiotic-resistant organisms were uncommon causes of infection for all survey years.

Interpretation: In CNISP hospitals, there was a decline in the prevalence of health care-associated infection in 2017 compared with previous surveys. However, strategies to prevent infections associated with medical devices should be developed. Apart from MRSA, few infections were caused by antibiotic-resistant organisms.