E-coli infection in humans linked to poultry

The study, published in the American Society for Microbiology’s open access journal mBio, provides evidence that the E.coli found in fresh poultry products can be passed to people, leading to bladder infections and other serious conditions.

The research, “Escherichia coli ST131-H22 as a Foodborne Uropathogen,” was led by a multi-centre research team led by Lance B. Price, director of the Antibiotic Resistance Action Centre (ARAC) at the George Washington University. It has shown that there are multiple strains of E.coli. ST131 and that one pathogen in particular may be passed to people via contaminated poultry meat.

Professor Price and his colleagues conducted a 1 year longitudinal study where they analysed retail chicken, turkey and pork purchased from every major grocery chain in Flagstaff, Arizona. During the same year, the team also collected and analysed urine and blood isolates taken from patients seen at Flagstaff Medical Centre, the only major hospital in the town.

E.coli in nearly 80% of meat samples

The team found E.coli in nearly 80% of the 2,452 meat samples and in 72% of the positive urine and blood cultures from patients. E. coli ST131 was the most common type infecting people and was also present on the meat samples.

They then looked at how closely related these bacteria were to one another, or importantly, whether people had acquired them from poultry.

So, they studied the genomes of the E.coli cells and discovered that almost all of the E.coli ST131 on the poultry products belonged to a particular strain called ST131-H22 and carried genes that helps E.coli thrive in birds. This same poultry-adapted strain was also found to be causing UTIs in people.

E.coli going from poultry to people

Professor Price, who is also a Professor of Environmental and Occupational Health at Milken Institute SPH, said: “In the past, we could say that E.coli from people and poultry were related to one another, but with this study, we can more confidently say that the E. coli went from poultry to people and not vice-versa.”

Poultry products are not currently routinely tested for the kind of E.coli strains that cause UTIs, but the findings underscore the importance of cooking poultry thoroughly and handling it carefully in the kitchen.

Cindy Liu, chief medical officer at ARAC, added: “This particular E.coli strain appears capable of thriving in poultry and causing disease in people. Poultry products could be an important vehicle for bacteria that can cause diseases other than diarrhoea.

“We are now working to measure what proportion of UTIs might be caused by foodborne E.coli by looking at all E.coli strains, not only ST131,” she added.