Contexte Dans une étude de prévalence ponctuelle en 2015, le Clostridioides difficile 027, un ribotype hypervirulent, était absent des établissements de santé en Suisse. Fin 2016, nous avons détecté une épidémie d’infection à C. difficile (CDI) avec le ribotype 027 dans plusieurs hôpitaux du même réseau hospitalier. Méthodes Les premiers cas de CDI dus au ribotype 027 ont déclenché une enquête sur l’épidémie, y compris le séquençage du génome entier (WGS) pour identifier les souches épidémiques.
Background In a 2015 point prevalence study, Clostridioides difficile 027, a hypervirulent ribotype, was absent from healthcare institutions in Switzerland. In late 2016, we detected an outbreak of C. difficile infection (CDI) with ribotype 027 occurring across several hospitals in the same hospital network. Methods The first cases of CDI due to ribotype 027 triggered an outbreak investigation, including whole genome sequencing (WGS) to identify outbreak strains. Findings We identified 28 patients with CDI caused by ribotype 027 between December 2016 and December 2017, out of which twenty were caused by a single clone. Commonalities among these patients were hospitalization in the same room or on the same ward, receiving care from the same healthcare workers, and shared toilet areas. In addition to the epidemiological links suggesting possible transmission pathways between cases, WGS confirmed the clonality of this C. difficile 027 outbreak. The outbreak was contained by isolation precautions, raising awareness among healthcare workers, harmonizing diagnostic algorithms, and switching to a sporicidal agent for environmental disinfection. Of note, neither default gowning and gloving nor handwashing with water and soap were implemented. Conclusions This C. difficile 027 outbreak was recognized belatedly due to lack of screening for this ribotype in some hospitals, and was contained by a swift response with simple infection prevention measures and adapting the laboratory approach. In order to have a better understanding of C. difficile epidemiology, diagnostic approaches should be standardized, CDI declared notifiable, and longitudinal data on prevalent ribotypes collected in countries where this is not established.