Isolation of carbapenem-resistant Pseudomonas aeruginosa, and other gram-negative ESKAPE organisms of concern from raw meat diets for dogs in the United Kingdom

Raw meat diets for pets have been demonstrated to be contaminated with potentially pathogenic, zoonotic and antimicrobial-resistant bacteria. The so-called ESKAPE organisms (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) are an emerging threat in companion animal medicine and are frequently associated with antimicrobial-resistant infections. Here we present the novel finding of Acinetobacter baumannii complex, Pseudomonas aeruginosa and Enterobacter spp., within samples of commercially available frozen raw meat diets for dogs in the United Kingdom. These bacteria were isolated incidentally from food samples tested as part of a wider study. Bacterial species were confirmed by MALDI-TOF MS, and isolates demonstrated resistance to highest priority critically important antibiotics on antimicrobial susceptibility testing by disc diffusion, including one carbapenem resistant P. aeruginosa isolate. Whole genome sequencing indicated the presence of multiple important intrinsic and acquired resistance genes across isolates, including the extended-spectrum beta-lactamase genes blaIMP-42 (P. aeruginosa) and blaSHV-66 (E. hormaechei), as well as P. aeruginosa sequence types associated with human clinical disease. This is the first report of the isolation of antimicrobial-resistant gram-negative ESKAPE organisms from raw meat diets for pets in the UK, and further highlights the potential human and animal health risks associated with this diet choice.