Clothing as microbial fomites in an equine veterinary hospital—Could interventions reduce nosocomial infection risk?

Background
Clothing in human medical environments has been shown to be contaminated with micro-organisms. There is little work in this area in the veterinary environment and none in equine veterinary environments.

Objectives
To characterise microbial contamination of veterinary clothing throughout a work shift in an equine hospital. The pattern could help determine whether an intervention could reduce contamination.

Study Design
Cross-sectional, observational pilot study of staff at B&W Equine Hospital in February 2023. The study used convenience sampling of staff clothing.

Methods
Ninety-two swabs from the clothing of 46 staff were taken at three time points (start of the day [AM], lunch and end of the day [PM]). Samples were cultured with colony-forming units (CFUs) per swab, and the genus of the microbe present was identified. Statistical analysis was performed.

Results
Five genera of microbes were identified on clothing. Veterinarians became significantly more contaminated from AM to PM (p = 0.034). All groups of staff arrived at work already contaminated. All AM samples from staff had Streptococcus spp. present. Rhodococcus spp. were not present on nonclinical staff.

Main Limitations
Small sample size not representative of all equine hospitals. Hospital-based not representative of ambulatory practices. Volunteer bias and the use of a nonprobability sampling method. Genetic sequencing not performed to determine the species of the microbe present.

Conclusion
This study found that veterinarians became significantly more contaminated throughout the day. This suggests that a simple intervention such as changing outer layers of clothing at lunchtime could reduce contamination levels. All groups were contaminated on arrival to work, suggesting that in-house laundering to regulate the cleanliness of uniforms could reduce microbial contamination. To reach a full conclusion on the diversity of contamination, further research, including full identification of microbes, is required.