Analysis of risk factors associated with antibiotic-resistant Escherichia coli.

This research studied the risk factors associated with the development of antibiotic-resistant E. coli in horses. It was found that horse hospitals in North West England are primary sources of these resistant strains, and that horses receiving oral antibiotic treatment, those hospitalized with gastrointestinal issues, and aging horses, were more likely to shed the antibiotic-resistant bacteria in their feces.

Study Design and Sample Collection

• The research compared fecal samples from 138 horses within a hospital settings and non-hospital settings (livery stable and riding school) located in North West England.
• A total of 264 samples were examined to identify the prevalence of different bacteria including E. coli, Salmonella, and Campylobacter and the rates of antimicrobial-resistant E. coli strains.

Key Findings

• Within the collected samples, Campylobacter jejuni was detected only in hospitalized horses at a rate of 1.1%, while no Salmonella was identified.
• The study found the hospital to be the primary source of both resistant and multi-drug-resistant (MDR) E. coli strains.
• Horses that were hospitalized for gastrointestinal issues were significantly likelier to shed antibiotic-resistant E. coli in their feces.
• Receipt of oral antibiotics, multiple antimicrobial treatments in hospital, and being a gelding (a castrated male horse), were also identified as risk factors associated with shedding of antibiotic-resistant E. coli.
• Intriguingly, an inverse relationship was observed between the administration of intravenous antibiotics and the shedding of resistant E. coli strains.
• Multi-drug-resistant (MDR) E. coli was associated with hospitalization, antimicrobial treatment received in the hospital, and increased age of the horse.

Implications of Study

• This research shows that equine hospitals in this particular geographical location are key reservoirs of antimicrobial-resistant and MDR E. coli, but not of Salmonella or Campylobacter.
• The study suggests the need for moderation in the use of antimicrobial treatments on hospitalized horses to reduce exposure and fecal shedding of resistant pathogens.