# Characterization of Adult and Pediatric Healthcare-Associated and Community-Associated Clostridioides difficile Infections, Canada, 2015–2022

## TL;DR

This study analyzed Clostridioides difficile infections in Canadian adults and children from 2015 to 2022, finding decreasing rates and changes in infection sources and strains.

## Contribution

The study provides updated national surveillance data on CDI epidemiology and molecular trends in both adult and pediatric populations in Canada.

## Key findings

- Adult healthcare-associated CDI rates decreased by 19.9%, while community-associated rates remained stable.
- Pediatric healthcare-associated CDI rates decreased by 29.6%, and community-associated CDI decreased by 58.3%.
- Ribotype 106 replaced RT027 as the most common strain, with RT027 linked to adult patients and severe outcomes.

## Abstract

We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult and pediatric patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2022. Of 30,824 reported CDI cases, 94.9% (29,250/30,824) were among adult (73.2% HA; 26.8% CA) and 5.1% (1,574/30,824) pediatric (77.6% HA; 22.4% CA) patients. During the study period, adult HA CDI rates decreased by 19.9% and CA CDI rates remained stable; pediatric HA CDI rates decreased by 29.6% and CA CDI decreased by 58.3%. Ribotype (RT) 106 was most common among both groups and replaced RT027 as the predominant strain type. RT027 was most associated with adult patients, HA acquisition, severe CDI, and severe outcomes. Moxifloxacin resistance was higher in adult than pediatric cases; clindamycin and rifampin resistance rates were similar between groups. Continued national surveillance is integral to understanding the epidemiology of adult and pediatric CDI in Canada and informing prevention efforts.