A review of quantitative microbial risk assessment in the management of Escherichia coli O157:H7 on beef Geraldine Duffy a, * , Enda Cummins b , Pa ´draig Nally b , Stephen O’ Brien a , Francis Butler a a Department of Food Safety, Ashtown Food Research Centre, Teagasc, Ashtown, Dublin 15, Ireland b Biosystems Engineering, School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Earlsfort Terrace, Dublin 2, Ireland Received 15 March 2006; received in revised form 24 April 2006; accepted 24 April 2006 Abstract Since Escherichia coli O157:H7 first emerged as a food borne pathogen in the mid 1980s, it has been linked to many cases of food poisoning across the world. While multiple sources and routes of transmission for this pathogen are now recognised, beef and beef prod- ucts remain an important vehicle of the pathogen and continue to be linked to outbreaks across the developed world. Much research has been directed at E. coli O157:H7 transmission, survival and control in the beef chain and this paper presents an overview of current knowledge on this pathogen in the beef chain from primary production through slaughter, processing, distribution, final preparation and cooking. In order to strategically manage E. coli O157:H7 and to devise approaches to reduce the public health risk posed, many national and international groups have applied quantitative risk assessment techniques to model the risk posed by E. coli O157:H7 in beef, particularly in ground/minced beef which is most often linked with infection. This paper reviews these quantitative risk assessments and their application in managing the risk posed by E. coli O157:H7 in beef. Ó 2006 Elsevier Ltd. All rights reserved. Keywords: E. coli O157:H7; Quantitative risk assessment; Beef 1. Introduction to quantitative risk assessment Risk analysis is a valuable tool in the management of microbial food safety issues and can provide a systematic approach for the regulatory authorities and the food indus- try to control the risk posed by a pathogen in a particular food commodity. Risk analysis consists of three elements: risk assessment, risk management and risk communication. Risk assessment is the scientific part of the process in which the hazards are identified and the risk posed by that partic- ular hazard (i.e. pathogen) is calculated. The principles of risk assessment including the four stages involved (hazard identification, exposure assessment, hazard characterisa- tion and risk characterisation) are outlined by the Codex Alimentarius Commission (Codex, 1999). Each of the stages is summarised below. 1.1. Hazard identification A hazard is defined as an agent having an adverse effect on the public health of the human population and may pose a short term, chronic, or fatal risk to a person. The identification of microbial hazard associated with a partic- ular food is generally based on information generated from routine microbial analysis of the commodity or from an epidemiological linkage of a particular pathogen with a case of food borne infection. 1.2. Exposure assessment Exposure assessment is a quantitative estimation of the presence of a contaminant in a serving of food at the time of consumption, or as close to this stage as is scientifically possible and practical. However, the final estimation of the 0309-1740/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.meatsci.2006.04.011 * Corresponding author. Tel.: +353 18059500; fax: +353 18059550. E-mail address: Geraldine.Duffy@teagasc.ie (G. Duffy). www.elsevier.com/locate/meatsci Meat Science 74 (2006) 76–88 MEAT SCIENCE