Tabloids have repeatedly warned the people for superbugs on chicken meat, after researchers had convincingly shown that the chicken filets that we buy are contaminated with ESBL-producing bacteria, mainly E. coli. Widely considered a public health threat, it was a decisive argument to insist on reductions in antibiotic use in the agricultural industry in the Netherlands. Yet, whether meat contamination constitutes a risk for human health is unknown. This was now quantified, with surprising results.
The authors – experts in the field of food safety – used a model (the swift Quantitative Microbiological Risk Assessment, sQMRA), which describes the change in the numbers of microorganisms on food, starting at the retail and from there meticolously incorporating every step until eating. For simplicity, I only describe the results for chicken and beef (and not for veal, pork and mutton).
We start with a prevalence of ESBL E. coli of 67% and 3-8% on chicken and beef, respecively, with estimated concentrations of 1,33 and 0,875 CFU/g for chicken and beef, respectively. Then they go ballistic on quantifying the effects of pre-retail procedures, heating (if your beef is eaten raw or cooked medium or well-done), storage at home and cross-contamination during food preparation, to derive at the number of ESBL E. coli during a meal. As they also seem to know how what we eat (in what form and how prepared) they calculated the exposure to these bacteria through food per year for an avearge Dutch citizen.
Surprisingly, it is the filet Americain (beef eaten raw, very tasteful) that appears to be our major “threat”. On average the Dutch are exposed to 18 CFU ESBL E. coli in a portion filet Americain, compared to 1.75 CFU when eating chicken. Of all human exposure to ESBL E. coli per year, 78% is estimated to come from beef (ie, filet americain) and 18% from chicken meat. The latter almost exclusively results from cross-contamination during food preparation, rather than eating the cooked meat.
Tasty food for thought for our risk assessments of ESBL contamination on meat. Just to let you know, as the tabloids apparently missed it.