The work has shown that it is realistic to expect that at least a fraction of the human exposure to Campylobacter originate from Campylobacter in chickens. The outcome of the risk modelling reveals that important factors for human exposure to Campylobacter are the broiler flock prevalence and hence, the prevalence in retail chickens, the Campylobacter concentration on positive products, and the extent of cross-contamination in private kitchens during food handling. Further, the model indicates that the prevalence of the Campylobacter positive chickens is not changed significantly during the slaughter processes assuming that the degree of cross-contamination is relatively low. However, the concentration of Campylobacter on the positive chickens will decrease. The concentration of Campylobacter on the positive chickens is important in relation to the risk of becoming infected.

In order to outline risk management options, three distinct ways of reducing the probability of exposure and illness were analysed: i) by reducing the prevalence of Campylobacter positive flocks; ii) by reducing the concentration of Campylobacter on the contaminated chickens; or iii) by improving the relative level of hygiene during food handling in private kitchens. The simulations showed that altering the broiler prevalence, the Campylobacter concentration on positive chickens, and the level of food hygiene could reduce the probability of getting ill from Campylobacter in chickens. To obtain a reduction in human cases by, for example, a factor 25, the flock prevalence should be reduced by a factor 25. A similar reduction in the number of human cases could be obtained by reducing the concentration of Campylobacter on the contaminated chickens by a factor 100 (2 log cfu pr g), or by improving the level of food hygiene in private kitchens by a factor 25.

Danish Veterinary and Food Administration