Quantification of Salmonella and Yersinia on pork carcasses by simulation modelling

Stagnation in the success of control programmes in pig production in Denmark has led to an increased interest in the development of alternative control strategies such as decontamination of carcasses to further decrease the attribution of pork meat to human foodborne illness. This project sets out to develop a model for quantitative estimation of slaughterhouse output of Salmonella and Yersinia . Distributions of the occurrence of Salmonefla, Yersinia and E. coli on pork carcasses are based on the analysis of paired faecal samples and carcass swabs from 2880 animals originating from four abattoirs. By combining the estimated quantity of faecal contamination of carcasses with a semi-quantitative distribution of the number of Safmoneffa or Yersinia per gram faeces, an output distribution describing the number of Salmonella or Yersinia bacteria per carcass can be established. In order to validate the model, carcass swabs, analysed for Salmonefla and Yersinia serve as control. After the model has been validated, the effect of various decontamination methods on human exposure to foodborne pathogens in pork will be evaluated in both economic terms as well as with regard to public health impact