Scientific Opinion on a Quantitative Microbiological Risk Assessment of Salmonella in slaughter and breeder pigs

Abstract

This Quantitative Microbiological Risk Assessment (QMRA) represents a major step forward in terms of modelling Salmonella in pigs from farm to consumption as it takes into account the variability between and within EU Member States (MSs). Around 10-20% of human Salmonella infections in EU may be attributable to the pig reservoir as a whole. From the QMRA analysis it appears that an 80% or 90% reduction of lymph node prevalence should result in a comparable reduction in the number of human cases attributable to pig meat products. Theoretically, according to the QMRA the following scenarios appear possible (a) by ensuring that breeder pigs are Salmonella-free a reduction of 70-80% in high prevalence MSs and 10-20% in low prevalence MSs can be foreseen; (b) by feeding only Salmonella-free feedstuffs, a reduction of 10-20% in high prevalence MSs and 60-70% in low prevalence MSs can be foreseen; and (c) by preventing infection from external sources of Salmonella (i.e. rodents and birds) a reduction of 10-20% in slaughter pig lymph node prevalence can be foreseen in both high and low prevalence MSs. A hierarchy of control measures is suggested -a high prevalence in breeder pigs needs to be addressed first, followed by control of feed and then control of environmental contamination. Also according to the QMRA, for each MS, a reduction of two logs (99%) of Salmonella numbers on contaminated carcasses would result in more than 90% reduction of the number of human salmonellosis cases attributable to pig meat consumption. The control of Salmonella in pig reservoir in the EU is a reasonable objective. The EU Salmonella control strategy in pigs should be continuously evaluated to identify possible improvements. KEY WORDSSalmonella, pigs, pig meat, QMRA, control, prevention, risk assessment, epidemiology 1 On request from the European Commission, Question No EFSA-Q-2006-176, originally adopted on 11 March 2010.After identification of modelling errors in the QMRA report by the consortium (grant beneficiary), this opinion was corrected, the current annex with explanations for the corrections of the errors added, and the corrected opinion adopted on 21 October 2010. The changes were made in Section 6 and corresponding conclusions, and are specified in Appendix C and Appendix E. SUMMARYFollowing a request from the European Commission, the Panel on Biological Hazards was asked to deliver a scientific opinion on a Quantitative Microbiological Risk Assessment (QMRA) of Salmonella in slaughter and breeder pigs. The assessment would provide the input for a future cost/benefit analysis of setting a target for reduction in slaughter pigs at EU level. EFSA commissioned a QMRA modelling the pig meat food chain from farm to fork. The QMRA model was based on input data from the baseline studies of Salmonella in breeder and slaughter pigs, and other relevant data. The QMRA represents a major step forward in terms of modelling Salmonella in pigs from farm to consumption as it takes into account the variability between and within EU M...

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