A vaccine was the only viable method for reducing the levels of campylobacter in the supply chain, a report said. It claimed farmed chickens’ immune systems did not develop fast enough to fight off campylobacter by themselves, before they were sent for slaughter.
Developing vaccines to unlock a greater immune response in broiler chickens, or finding a way to speed up their immune development, might cut the amount of campylobacter in the supply chain, the researchers from the University of Liverpool said.
Campylobacter in the supply chain
Researcher on the study Paul Wigley said: “Vaccines that focus on a cell-mediated immune response, or alternatively some way of speeding up the production of antibodies in broiler chickens, may offer more promising routes to controlling campylobacter, and ultimately reducing the amount of contaminated chicken in our supermarkets.”
The scientists monitored bacteria levels in farmed chickens after giving them a strain of campylobacter. They found that bacteria levels only began to decrease after seven weeks, suggesting their immune response did not begin to mature until they were at least six weeks old.
“It’s likely to be very challenging to produce a protective immune response in broiler chickens before slaughter age, which is around six weeks of age.”
Four out of every five cases of campylobacter infection come from contaminated poultry. It costs the economy up to £900M a year, the researchers said.
Human cases of campylobacteriosis
Meanwhile, the number of human cases of campylobacteriosis fell more than 100,000 last year, according to the Food Standard Agency’s (FSA’s) latest campylobacter survey. The results showed 7% of chickens tested positive for the food poisoning bacterium, within the highest band of contamination, compared with the same period the previous year.
The FSA hailed the report as a landmark achievement.
FSA chairman Heather Hancock said: “The challenge we set of reducing the number of people who get ill from campylobacter has been achieved. In the absence of any other clear indicators, we can reasonably say that the work that we and the food industry have done from farm to fork has given us this really positive result for public health.
“We commend the efforts of the larger retailers and the major processing plants who supply them, all of which have shown significant improvement, and many have achieved the target we set to reduce the highest levels of campylobacter. They have invested a lot of effort and money into interventions to tackle the problem.”