Clostridioides (Clostridium) difficile in neonatal foals and mares at a referral hospital.
Authors: Weese Jeffrey Scott, Slovis Nathan, Rousseau Joyce
Journal: Journal of veterinary internal medicine
Summary
# Editorial Summary: *Clostridioides difficile* in Neonatal Foals and Mares *Clostridium difficile* epidemiology in equine neonates remains poorly understood, yet this knowledge is critical for implementing effective biosecurity protocols in referral hospital settings. Weese, Slovis and Rousseau conducted longitudinal surveillance of 113 foals and their dams admitted to a neonatal intensive care unit, collecting rectal swabs at admission and approximately three-day intervals, then culturing isolates and characterising them via toxin gene PCR and ribotyping. The prevalence of shedding was notable: 44% of foals and 31% of mares tested positive for *C. difficile* in at least one sample, with 25% of all samples yielding the organism; interestingly, no correlation existed between hospitalisation duration and bacterial detection. Ribotype 078 dominated the isolates, though 23 different ribotypes were identified overall, and critically, only 40% of foals shedding the organism twice during their stay harboured the same strain, suggesting frequent acquisition of new strains rather than persistent colonisation. For equine professionals, these findings underscore that *C. difficile* detection in asymptomatic animals is common and transient in hospitalised neonates, complicating interpretation of diagnostic results and indicating that infection control measures should prioritise environmental management and handwashing over attempts to eliminate carriage, whilst recognising that positive cultures may reflect environmental exposure rather than clinically significant infection.
Read the full abstract on PubMed
Practical Takeaways
- •C. difficile is common in neonatal foals and mares at referral hospitals, but asymptomatic shedding does not necessarily indicate disease outbreaks or require intervention
- •Infection control protocols should focus on managing the opportunistic nature of this pathogen rather than attempting to eliminate carrier animals
- •Consider that multiple strains can circulate within a facility; positive cultures on different dates may represent new exposures rather than persistent infection
Key Findings
- •C. difficile was isolated from 25% of all samples (103/409), with 31% from foals and 19% from mares
- •44% of foals and 31% of mares shed C. difficile during hospitalization despite no identifiable disease cluster
- •23 ribotypes identified with ribotype 078 predominating; only 40% of foals with repeat positive cultures carried the same strain
- •No association found between hospitalization day and C. difficile isolation, suggesting transient colonization patterns