Occurrence of Salmonella on pork on the island of Ireland and an assessment of the risk factors

Project start date: 1 July 2005
Project status: Completed
Project type: Food safety
Discipline: Microbiology and food hygiene
Principal researcher/s: Dr Geraldine Duffy, Teagasc Food Research Centre, Dublin
Collaborator/s: Dr Patrick Naughton, University of Ulster, Prof Seamus Fanning, Dr Nola Leonard & Dr Francis Butler, University College Dublin, Dr Robert Madden, Queen’s University Belfast

Research objective

Salmonella species have been consistently associated with food borne illness and are the second most common cause of bacterial food borne illness. Pork has now taken over from eggs as one of the most important food borne sources of Salmonella. Outbreaks of S. Typhimurium DT104 in Dublin in 1998 and the West of Ireland in 2000 which were linked to cooked ham resulted in 78 people and 140 people becoming ill respectively.

In the Republic of Ireland and Northern Ireland, two different approaches are taken to control Salmonella in pigs. In the Republic of Ireland, every pig herd is tested on the farm on a quarterly basis to establish its Salmonella status. The category status assigned determines the treatment at slaughter and affects the need for further treatment or the destination of the meat. In Northern Ireland, there is no statutory requirement for Salmonella testing in pork. There is a voluntary system in place which tests juice from meat samples for Salmonella antibodies as they go through the abattoir. Results are compared to the national average and specialist advice is given to farms producing pigs which display high levels of contamination.

The overall aim of this project was to assess the effectiveness of current control programmes and the public health risk and economic cost attributable to Salmonella on pork on the island of Ireland. This project aimed to draw together and build on existing work in this area and carried out a risk assessment of the product pathway from farm to retail level. The research has provided the basis for key decisions on changes to the Regulatory Salmonella control programmes for pigs by the Department of Agriculture, Fisheries and Food in the Republic of Ireland. The research and developed risk model are also being fed into a European Quantitative Risk Assessment for Salmonella in pigs being developed by the European Food Safety Authority (EFSA).

Research report

Other outputs

Duggan, S.J., Mannion, C., Prendergast, D.M, Leonard, N., Fanning, S., Gonzales-Barron, U., Egan, J., Butler, F. and Duffy, G. (2010). “Tracking the Salmonella status of pigs through the slaughter process in the Republic of Ireland”. Journal of food Protection 73, 12: 2148-2160.

Gonzales Barron, U., Soumpasis, I., Butler, F., Duggan S., Prendergast, D. and Duffy, G. (2009). “Estimation of prevalence of Salmonella spp. on pig carcasses and pork joints using a quantitative risk assessment model aided by meta-analysis”. Journal of Food Protection, 72(2): 274-285.

Gonzales Barron, U., Soumpasis, I., and Butler, F. (2009). “An appraisal of the use of meat juice serology monitoring data for estimating prevalence of caecal Salmonella carriage of pigs at slaughter by means of herd-level and animal-level simulation”. Journal of Food Protection, 72(2): 286-294.

Gonzales-Barron, U., Soumpasis, I., Butler, F. and Duffy, G. (2008). ”A comparison between herd-level and animal-level simulation for estimation of prevalence of Salmonella in caecal contents of slaughter pigs in Ireland from meat juice serology”. Risk Analysis. In press.

Gonzales Barron, U., Bergin, D. and Butler, F. (2008). “A meta-analysis study of the effect of chilling on Salmonella prevalence on pork carcasses”. Journal of Food Protection, 71 (7) 1330 – 1337.

Mannion, C., Egan, J. Lynch, P. Fanning, S. and Leonard, N. (2008). “An investigation into the efficacy of washing trucks following transportation of pigs – a Salmonella perspective”. Foodborne pathogens and disease 5 (3).

Prendergast D.M., Duggan, S.J., Gonzales-Barron U, Fanning S, Butler F, Cormican M, and Duffy G. (2009). “Prevalence, numbers and characteristics of Salmonella spp. on Irish retail pork”. International Journal of Food Microbiology 131(2-3):233-239.

Prendergast, D.M., Duggan, S.J., Fanning, S., Cormican, M., Gonzales Barron, U., Butler, F. and Duffy, G. (2008). “Prevalence and numbers of Salmonella spp. and Enterobacteriaceae on pork cuts in abattoirs in the Republic of Ireland”. J Applied Microbiology. 105(4): 1209-1219.