Antimicrobial-resistant Enterobacteriaceae recovered from companion animal and livestock environments.

This research investigates the prevalence of antibiotic-resistant bacteria on surfaces frequently contacted by humans in various animal environments. The findings highlight that these surfaces, particularly in livestock environments, can serve as significant reservoirs for transmitting antibiotic-resistant bacteria, posing potential risks to public health.

Objective of the Research

• The main objective of this study was to estimate the prevalence of specific antibiotic-resistant bacteria on surfaces frequently contacted by humans in different animal environments. The researchers aimed to identify the places with higher levels of bacteria expressing resistance to antibiotics, which could serve as major sources for the zoonotic transmission (transfer of diseases from animals to humans) of antibiotic-resistant bacteria.

Research Methodology

• Environmental surface samples were collected from various animal environments such as companion animal shelters, private equine facilities, dairy farms, livestock auction markets and county fair livestock areas. These samples were harvested using electrostatic cloths.
• The samples were then screened for Enterobacteriaceae (a large family of bacteria) expressing resistance to numerous antibiotics including AmpC, extended-spectrum beta-lactamase (ESBL), carbapenemase (CRE), and fluoroquinolones.

Findings of the Study

• The study found that livestock auction markets and county fairs had higher levels of bacteria expressing resistance to both cephalosporin and fluoroquinolone, compared to equine facilities, dairy farms, and companion animal environments.
• Private equine facilities manifested more bacteria with resistance to cephalosporin than companion animal shelters, but less resistance to fluoroquinolones.
• It was suggested that the regular use of extended-spectrum cephalosporins in livestock could have led to increased levels of cephalosporin resistance in livestock environments when compared to companion animal and equine facilities.

Implications of the Study

• Detection of antibiotic-resistant bacteria on surfaces commonly contacted by humans in varying animal environments suggests that these environments may serve as reservoirs for the zoonotic transmission of antibiotic-resistant bacteria and resistance genes.
• The findings highlight the need for interventions aimed at significantly reducing the prevalence of antibiotic-resistant bacteria in animal environments, as this can substantially help protect both animal and public health.