Food Safety and Inspection Service FOOD SAFETY AND INSPECTION SERVICE
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Risk Assessment of E. coli O157:H7 in Beef

Quarterly Progress Report ­ November 1998

This is the first formal quarterly report of the Food Safety and Inspection Service Office of Public Health and Science (FSIS/OPHS) Risk Assessment of E. coli O157:H7 in Beef. The risk assessment project was initiated on June 16, 1998.

The overall goals of the assessment are to: 1. quantitatively model, with attendant uncertainty, human illnesses caused by E. coli 0157:H7 in beef in the United States and to compare these results with national estimates of illnesses derived from observed epidemiological data; 2. identify the occurrence and levels of the pathogen at points along the farm-to-table continuum and the contribution of these points to the number of human illnesses; 3. quantify the effects of various mitigation strategies in reducing the number of human illnesses; 4. identify future research needs; 5. document risk assessment methods and evidence for future assessments; 6. document changes in the risk assessment model and its inputs; 7. effectively communicate the results to all interested parties--government, consumer groups, industry, the scientific community and the general public.

In the past five and one-half months FSIS has: (a) formed a risk assessment team and formalized the team's charter; (b) issued a public announcement of the risk assessment (Fed. Reg., Vol. 63, p. 44232); (c) begun gathering background scientific literature and data on E. coli O157:H7 and the beef production process; and (d) held a public meeting on October 28 to solicit input and advice from interested parties and released a draft report, "Preliminary Pathways and Data for a Risk Assessment of E. coli O157:H7 in Beef."

Risk Assessment Team and Team Charter

The core risk assessment team consists of a multidisciplinary group of analysts with proficiency in the methods of risk assessment and graduate training in veterinary medicine, epidemiology, microbiology, ecology, economics, and public policy. The team consists of seven members: Peg Coleman, MS, FSIS/OPHS Epidemiology and Risk Assessment Division (ERAD); Peter Cowen, PhD, DVM, FSIS/OPHS/ERAD and North Carolina State University; Eric Ebel, DVM, MS, FSIS/OPHS Emerging Pathogens and Zoonotic Diseases Division (EPZDD); Clare Narrod, PhD, American Association for the Advance of Science (AAAS) Fellow, FSIS/OPHS/ERAD; Tanya Roberts, PhD, US Department of Agriculture, Economic Research Service; Wayne Schlosser, DVM, MPH, FSIS/OPHS/EPZDD. The team is led by Mark Powell, PhD, AAAS Fellow, FSIS/OPHS/ERAD.

The team charter states that a baseline risk assessment will serve to identify risk factors and high-risk pathways under current practices of production, slaughter, processing, transportation, storage, and preparation. The baseline risk assessment will inform a distinct FSIS policy analysis that will identify feasible risk mitigation options for further comparative analysis. A subsequent comparative risk assessment will provide decision-makers with information concerning the efficacy of the alternative mitigation strategies and a tool to evaluate these strategies to decrease the number of human illnesses resulting from E. coli 0157:H7 in beef. FSIS's goal is to issue a draft report for external review and comment in June 1999, a final technical report in July 1999, and a final report for the general public in August 1999.

Public Announcement

A public announcement of the risk assessment was published in the Federal Register on August 18, 1998 (Vol. 63, p. 44232, ). The purpose of the notice was to: (1) give public notice of FSIS' intent to conduct the risk assessment; (2) solicit from the public scientific information and data that would

be relevant to conducting the risk assessment; and (3) announce the October 28 public meeting. The Federal Register announcement also established a docket (Docket #98-037N) for receiving public comments and submissions of data or analyses regarding the assessment.

Public Meeting and Release of Preliminary Pathways and Data

A public meeting was held in Arlington, VA on October 28, 1998. The purposes of the meeting were to: 1. solicit comment and input regarding the scope of the risk assessment, the analytical framework to be used in conducting the risk assessment, the scientific evidence acquired by the risk assessment team to date from the available literature, and the existing data gaps identified by the risk assessment team; 2. release the Preliminary Pathways and Data for a Risk Assessment of E. coli O157:H7 in Beef. The draft report was not intended to present results, preliminary or otherwise. Comments and additional data identified during the public meeting or submitted to the docket in response to the August 18, 1998 Federal Register Notice by January 8, 1999 will be evaluated for inclusion in the development of the draft risk assessment model. An electronic version of the draft report can be located at: Preliminary Pathways and Data.

The public meeting was attended by more than 60 individuals. After a welcome from Margaret Glavin, FSIS Deputy Administrator for Policy, Program Development, and Evaluation, Dr. Patty Griffin, the Chief of the Epidemiology Section at the National Center for Infectious Diseases at the Centers for Disease Control and Prevention, gave an overview of E. coli 0157:H7 microbiology and epidemiology. CDC currently estimates that each year in the U.S., there are 20,000 or more E. coli O157:H7 infections, with 500-1000 cases of hemolytic uremic syndrome, and 50-100 deaths. Dr. Griffin reported that CDC is in the process of revising these estimates. Dr. Richard Whiting of the Food and Drug Administration Center for Food Safety and Applied Nutrition gave a presentation on modeling growth and decline of E. coli O157:H7. Dr. Mark Powell gave an overview of the risk assessment team's goals for the meeting and described the proposed analysis plan. Dr. Eric Ebel, Dr. Tanya Roberts, Dr. Wayne Schlosser, and Peg Coleman provided, respectively, overviews of the production, slaughter, preparation, and public health segments of the farm-to-table risk assessment model. Each core team presenter underscored the significant data gaps identified in the draft "Preliminary Pathways and Data" report and the need for additional data (e.g., data on the prevalence of E. coli O157:H7 in raw beef trim prior to grinding). Public presentations were made by: Dr. Ann Hollingsworth, Keystone Foods Corporation; Dr. Larry Borchert, American Meat Institute; Dr. Peter Mrozinski, Qualicon, Inc.; Dr. Harless McDaniel, American Veterinary Identification Devices; Dr. John Sofos, Colorado State University; Richard Wood, Food Animal Concerns Trust; Nancy Donley, President, Safe Tables Our Priority; and Caroline Smith Dewaal, Director of Food Safety, Center for Science in the Public Interest. A complete transcript of the public meeting is on file in the FSIS docket.

A major theme running through the public comments was concern that the proposed scope of the analysis was limited to foods containing ground beef and thereby omitted other important sources of E. coli O157:H7 infections such as vegetables, produce, juice, water, and person-to-person transmission. FSIS officials explained that in order to make the analysis tractable and in light of resource and time constraints, the scope of the assessment would necessarily have to be delimited. The risk assessment model will be constructed to permit future iterations to incorporate a broader set of beef products. Furthermore, CDC is currently charged with estimating the total disease burden of E. coli O157:H7 from all products based on epidemiologic surveillance data. The scope of the assessment will be finalized after the January 8, 1999 close of the comment period on the draft preliminary pathways and data report.

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