Poultry industry linked to foodborne infections

A new study warns that modern large scale chicken farming may be helping dangerous food poisoning bacteria spread more easily creating new risks for human health.

Researchers from the Oxford University found that the rapid growth of industrial poultry farming has created ideal conditions for Campylobacter, a bacteria that causes food poisoning to grow spread and develop new traits.

Campylobacter is one of the world’s leading causes of diarrhea and food poisoning.

In the UK it causes around three and a half times more stomach illness cases each year than all other monitored foodborne bacteria combined.

The researchers said the global chicken population has increased about sevenfold since the 1960s reaching around 31 billion birds.

This growth has made it easier for bacteria carried by wild birds to spread among farm chickens. The team studied nearly 2,800 bacterial genomes collected from chickens and wild birds in 30 countries including the UK and the US between 1979 and 2024.

Genetic analysis showed that the bacteria had developed changes linked to modern farming conditions.

These included genes that help it resist antibiotics and survive more easily in large poultry farms.

Researchers warned that rising antibiotic resistance is making Campylobacter infections harder to treat.

The study’s lead author Sam Sheppard said the findings provide new evidence that human activities and environmental changes can increase the spread of infectious diseases.

He added that understanding how bacteria evolve will be important for reducing future risks of animal to human diseases and antibiotic resistant infections.