Surveillance from a network of Canadian acute-care hospitals indicates that carbapenemase-producing Enterobacterales (CPE) infections and colonizations remain uncommon but are rising rapidly, according to a study published in Antimicrobial Resistance and Infection Control.

Researchers with the Public Health Agency of Canada analyzed data from the Canadian Nosocomial Infection Surveillance Program (CNISP), reviewing eligible CPE isolates submitted by participating hospitals from 2010 to 2023, along with microbiologic information and patient characteristics and outcomes.

Earlier CNISP data from 2010 to 2014 showed no significant increase in CPE incidence, which involves bacteria resistant to multiple antibiotic classes. However, recent reports suggest that CPE rates are climbing in Canadian hospitals.

In 2023, 97 hospitals reported 138 CPE infections, representing an incidence of 0.14 per 10,000 patient-days, up from 0.03 per 10,000 patient-days in 2010. During the same period, CPE colonization rose from 0.02 to 0.78 per 10,000 patient-days.

Healthcare-associated (HA) CPE infections also increased between 2019 and 2023, from 0.05 to 0.09 per 10,000 patient-days, driven largely by seven hospitals that accounted for 53% of all HA-CPE infections in 2023.

The bacteria most frequently producing carbapenemases were Escherichia coli (29%), Klebsiella pneumoniae (22%), and Enterobacter cloacae complex (16%). The most common carbapenemase families were blaKPC (46%), blaNDM (29%), and blaOXA-48 (16%).

Hospital transmission is the main driver

Patients had a median age of 67 years, and most had pre-existing health conditions (84%). Thirty-day all-cause mortality was 19%. The majority of patients had no history of international travel (66%) or medical care abroad (74%), factors previously linked to CPE infection and colonization.

The authors warn that the exponential rise in CPE highlights gaps in current infection-control measures in Canadian hospitals.

“Our findings suggest that nosocomial transmission is driving the recent increase in CPE incidence in Canada,” the authors wrote. “Enhanced infection control, antimicrobial stewardship, and access to newer antibiotics are urgently needed.”