Multi-Criteria Decision Analysis for Pathogen Prioritization and On-Farm Interventions to Control Pathogens Transmitted from Pork to People in Canada.

The aim of this research was to conduct a formal multi-criteria decision analysis (MCDA) to prioritize pathogens transmitted from pork to people in Canada and to rank interventions available for on-farm control of Salmonella, a key foodborne pathogen of pork in Canada. This included the identification of important criteria, estimation of criteria importance (weighting), and collection of appropriate information for use in the MCDA process. A scoping review was conducted to identify available information for prevalence of foodborne zoonotic pathogens in the pork production chain in Canada. Published research studies and surveillance efforts were identified and relevant data was extracted. More data were available for Salmonella than other pathogens. The MCDA for prioritization of eight pathogens was carried out using PROMETHEE II, an outranking approach. Criteria that were used for prioritization were the prevalence of the pathogen in finisher-aged pigs, human burden of disease attributed to pork, and trade implications. Salmonella was ranked as the most important pathogen in most scenarios, followed by Yersinia, Toxoplasma, and Campylobacter. An expert consultation was carried out to estimate consumer perception for interventions to control Salmonella on-farm. Experts were asked to participate in on-line questionnaire that used a Delphi approach. They did not identify a difference among candidate interventions in terms of consumer perception. Canadian pork producers were surveyed to provide an estimate for practicality of on-farm interventions for Salmonella. Producers who used interventions scored them as more practical than those who did not. The intervention, ‘Use of meal feed’ was scored as more practical than ‘Acidification of feed or water’, ‘Antibiotics’, ‘Disinfection’, ‘Wet Feed’ (P < 0.05) but not significantly more practical than ‘Vaccination’. All interventions had a mean practicality score that was less than the midway score. Using the criteria for effectiveness, weight of evidence, cost, practicality and consumer perception, ‘Acidification’ ranked highest and ‘Vaccination’ second when consumer perception was the lowest weighted criteria. This was reversed when consumer perception was the highest weighted. This research identified information available for each of the conducted MCDA, however the quality of evidence was not consistent for all pathogens or interventions considered.