A series of factors has been highlighted by E.F.S.A. for consideration in designing national Campylobacter control measures or programs for chickens and chicken meat. E.F.S.A. recommends control programs be based on an integrated approach addressing both the chicken farms and the slaughter process. Further studies at national level could also allow better identification of risk factors for Campylobacter infections in each country.
E.F.S.A.’s study states batches of chickens infected with Campylobacter are 30 times more likely to produce carcasses contaminated with Campylobacter and that infected batches are also more likely to produce carcasses with higher numbers of Campylobacter on them. The report specifies, however, contaminated carcasses could also derive from non-infected batches of chickens, implying possible cross-contamination in the slaughterhouse.
Risk of contaminating carcasses with Campylobacter varied significantly between countries and slaughterhouses within the same country, and so did the quantity of Campylobacter found on the single carcasses, the study notes.
Other factors were also found to be linked to an increased risk of contamination of carcasses, including the age of the slaughtered chickens; some specific periods of the year when the chickens are slaughtered – with a contamination peak between July and September – and the time of the day when carcasses are processed – with a higher risk of contamination later in the day.
“Thinning” practices in chicken flocks also emerged as a factor increasing the likelihood of infection. These practices involve selecting within a flock a certain number of chickens to be sent to slaughter, while leaving the rest to continue growing. It is believed that during these practices, humans or other vectors may introduce Campylobacter and infect the remaining chickens.
In the European Union, campylobacteriosis is the most-frequently reported food-borne illness in humans. Poultry meat appears to be a major, if not the largest, source of Campylobacter infection in humans, according to a recent opinion of E.F.S.A.’s Biological Hazards (BIOHAZ) Panel . The risk for human health arises from consumption of under cooked meat or cross-contamination between foods.
The study just published by E.F.S.A.’s Zoonoses Data Collection Unit focuses specifically on contamination of chickens with Campylobacter in the early stages of the food chain: the beginning and at the end of the slaughter line, when the chickens arrive at the slaughterhouse and when their carcasses are chilled after slaughtering. The findings will complement the other information available on the subject, such as epidemiological studies on Campylobacter in chickens.