Resistance levels found
Less than 1 percent of beef and 4 percent of pork samples possessed an Extended Spectrum beta-lactamase (ESBL) or AmpC-expressing E. coli. No meat samples, before enrichment, had background or AmpC-/ESBL-phenotype E. coli counts above EU detection levels, indicating low numbers of these bacteria. However, post-enrichment, one beef, and four pork samples yielded AMR E. coli. Results were similar to the 2015, 2017, and 2019 surveys.

ESBL and AmpC enzymes confer resistance to cephalosporins. No beef and pork samples were positive for E. coli with resistance to last-resort carbapenem or colistin antimicrobials.

Most beef samples were from the UK, but some came from Ireland, Brazil, Poland, Scotland, and Spain. Most pork samples were domestic, but others were from Germany, Denmark, Belgium, Ireland, and the Netherlands. Samples were collected from retail across England, Scotland, Wales and Northern Ireland.

Two pork samples were positive for AmpC-producing E. coli, and two were positive for ESBL-producing E. coli. The beef isolate had an E. coli with an AmpC + ESBL-expressing phenotype.

Pet food AMR study
Another survey is gathering data on antimicrobial resistance in bacteria found in raw dog and cat food on sale in the UK.

In the five E. coli isolates, resistance was seen to some antibiotics. The beef isolate was resistant to all four cephalosporin antibiotics it was tested against (cefepime, cefotaxime, cefoxitin, and ceftazidime), while the pork isolates were resistant to at least two of these antibiotics. All five E. coli isolates resisted ampicillin but not amikacin, temocillin, or tigecycline.

Raw pet food does not undergo heat treatment meaning the final retail product can be contaminated with microorganisms, including pathogens and AMR bacteria.

Findings will enable the FSA to identify any risk to the public by cross-contamination during storing and handling of such products.

The survey involves collecting 280 dog and 100 cat food items on sale in the UK from March 2023 to February 2024. Before testing for AMR, samples will be tested for the detection and enumeration of E. coli, Salmonella, Campylobacter, Shiga toxin-producing E. coli, and Livestock-associated Methicillin-Resistant Staphylococcus aureus. Screening of AMR will include Extended Spectrum Beta Lactamases (ESBLs), AmpC, Carbapenems, and fluoroquinolones, as well as analysis for colistin resistance and the colistin-resistant MCR genes.

Another 140 dog and 50 cat products will have the packaging swabbed before opening and testing for the above contaminants. This data will indicate whether raw dog and cat food packaging is appropriate to prevent microbiologically contaminated meat liquid seepage during thawing and the potential to cross-contaminate other foods and surfaces within the home.