Effectiveness of steam cleaning technology on reducing the occurrence of ESKAPE organisms and Escherichia coli in the stables of an equine referral hospital.

Abstract: The "ESKAPE" bacteria include a group of organisms known for their multidrug resistance and potential association with nosocomial infections in human and veterinary hospitals. Objective: This study aimed to evaluate the effectiveness of steam cleaning in reducing the number of ESKAPE organisms on environmental surfaces from the stables of an equine veterinary referral hospital. Methods: Environmental sampling was performed at two timepoints (pre- and post-steam cleaning) on smooth metallic doors and rough rubber stable walls. Microbiological culture targeted ESKAPE organisms and Escherichia coli. Adenosine triphosphate (ATP) bioluminescence swabs were taken concurrently to compare their readings in relation to ESKAPE presence, and settle plates were used to assess aerosolised contamination. A selection of isolates obtained post-steam cleaning underwent whole genome sequencing (WGS). Results: Steam cleaning led to a significant reduction in ESKAPE organisms on smooth metal doors compared to rough rubber walls (52 % vs. 10 %, p- 0.004, 95 % CI). ATP swabs provided a quick indicator for cleanliness, however Spearman's correlation coefficient (ρ) failed to find a significant correlation with microbiological culture results (ρ = 0.082, p-0.467). No ESKAPE organisms were isolated from settle plates at any timepoint. WGS of ESKAPE isolates obtained post-steam cleaning (n = 17) identified resistance genes to at least four classes of antimicrobials in all isolates, while some isolates also carried "qacE" resistance genes to quaternary ammonium compounds (n = 6). Conclusions: This study provides novel data suggesting that steam cleaning was effective at reducing ESKAPE organisms on smooth surfaces and may offer an environmentally friendly alternative to chemical disinfectants.