Industrial poultry farming is accelerating the spread of a major foodborne disease - Phys.org

What the report says

Phys.Org, citing a University of Oxford report, says a new study from the Ineos Oxford Institute for Antimicrobial Research has linked the growth of industrial poultry production to a sharp rise in the spread of Campylobacter, a leading bacterial cause of diarrheal illness. The study, published in Proceedings of the National Academy of Sciences, examined nearly 2,800 Campylobacter genomes from chickens and wild birds in 30 countries, including the UK and U.S., with samples dated from 1979 to 2024.

According to the report, researchers found that the expansion of commercial chicken farming has increased Campylobacter movement by more than 100 times, enabling strains formerly associated with wild birds to circulate and mix within poultry populations. The article notes that global chicken numbers have grown sevenfold since the 1960s to about 31 billion birds, and that chickens now represent roughly 70% of bird biomass worldwide.

The Oxford team identified genetic changes associated with adaptation to poultry environments, including traits linked to antimicrobial resistance, oxidative stress tolerance, metal acquisition and motility. The study also used modeling to suggest that very large, dense flocks can absorb strains from multiple sources and allow some wild-bird-derived strains to persist in poultry even if they are not well adapted.

The findings matter because Campylobacter is a major foodborne pathogen, and antimicrobial resistance can make infections harder to treat. Phys.Org also referenced earlier IOI research associating most human Campylobacter infections in Oxfordshire with poultry meat. The study’s authors argue that understanding how intensive farming shapes bacterial evolution is important for reducing zoonotic and foodborne disease risks.