Phenotypic characterization of environmental Clostridioides difficile isolates from wastewater and seafood in Taiwan

Abstract

Clostridioides difficile (C. difficile) is a gram-positive, toxin-producing, spore-forming anaerobe, and leading cause of nosocomial antibiotic-associated diarrhea (AAD). C. difficile is present worldwide and the disease caused by this bacterium, C. difficile infection (CDI) affects individuals of all ages and health statuses. The spores formed by C. difficile are readily transmissible and can persist in animals, food, and environmental sources such as water and soil. The aim of this research was to complete phenotypic characterization of environmental C. difficile isolates to contribute to the first analysis of C. difficile environmental contamination in Taiwan. Assays were performed to evaluate the growth rate, colony morphology, sporulation efficiency, surface motility, and swimming motility. Notably, 078-lineage C. difficile isolates displayed significantly lower surface motility compared to toxigenic non-078 lineage isolates and non-toxigenic isolates. Also, toxigenic and non-toxigenic isolates of C. difficile demonstrated similar sporulation efficiency and swimming motility. The implications of C. difficile contamination in wastewater and seafood may suggest that more stringent wastewater treatment practices are needed and illustrate the importance of safe food handling practices. Moreover, having access to a complete profile for C. difficile isolates could help healthcare providers and researchers make better informed decisions in their respective lines of work.