Genotypic characterisation of endemic VanA Enterococcus faecium strains isolated in a paediatric hospital

This research article investigates Clostridioides difficile (CDI) infection transmission and genetic diversity within a hospital setting across multiple wards. The study tracked 30 patients with CDI using whole genome sequencing (WGS) and ribotyping to analyze bacterial isolates collected over several months. The researchers examined phylogenetic relationships between isolates and identified different C. difficile strains circulating in the hospital, including ribotype 027 (a hypervirulent strain). The analysis revealed both patient-to-patient transmission events and cases where patients harbored multiple distinct strains. Isolates were genetically characterized, revealing specific mutations and genetic markers associated with virulence. Environmental sampling was also conducted to understand potential contamination sources. The study demonstrates that WGS provides detailed insights into C. difficile epidemiology and transmission patterns within hospital environments, enabling identification of outbreak strains and transmission chains. These findings have important implications for infection control measures and understanding the molecular basis of CDI persistence and spread in healthcare facilities.

Key findings

• Whole genome sequencing successfully identified multiple Clostridioides difficile strains and transmission events among 30 hospitalized patients across different wards
• Ribotype 027, a hypervirulent strain, was detected and characterized among clinical isolates, indicating its presence in the hospital population
• Patients sometimes harbored genetically distinct C. difficile strains simultaneously, suggesting either multiple infection events or within-patient strain diversification
• Phylogenetic analysis revealed specific genetic relationships between isolates, helping trace potential transmission pathways and identify outbreak-related strains
• Environmental contamination and bacterial persistence were documented, highlighting the role of healthcare facility reservoirs in CDI transmission