title: Streamlined analysis for evaluating the use of preharvest interventions intended to prevent Escherichia coli O157:H7 illness in humans.
abstract: The U.S. Department of Agriculture Food Safety Inspection Service is responsible for ensuring the safety of meat, poultry, and egg products consumed in the United States. Here we describe a risk assessment method that provides quantitative criteria for decision makers tasked with developing food safety policies. To demonstrate the utility of this method, we apply it to a hypothetical case study on the use of an Escherichia coli O157:H7 cattle vaccine to prevent human illness caused by consuming beef. A combination of quantitative risk assessment methods and marginal economic analysis are used to describe the maximum cost per unit that would still allow the vaccine to be a cost-effective intervention as well as the minimum effectiveness it could have at a fixed cost. We create two economic production functions where the input is number of vaccinated cattle and the output is human illnesses prevented. The production functions are then used for marginal economic analysis to assess the cost/benefit ratio of using the vaccine to prevent foodborne illness. In our case study, it was determined that vaccinating the entire U.S. herd at a cost of between $2.29 and $9.14 per unit (depending on overall effectiveness of the vaccine) would be a cost-effective intervention for preventing E. coli O157:H7 illness in humans. In addition, we determined that vaccinating only a given fraction of the herd would be cost effective for vaccines that are less effective or more costly. For example, a vaccine costing $9.00 per unit that had a 100% efficacy but required 100% herd coverage for immunity would be cost effective for use in about 500,000 cattle each year-equating to an estimated 750 human illnesses prevented per annum. We believe this approach could be useful for public health policy development in a wide range of applications.
authors.affiliation: Risk Assessment and Residue Division, Office of Public Health Science, Food Safety Inspection Service, U.S. Department of Agriculture, Fort Collins, Colorado 80526, USA.
authors.forename: James
authors.initials: J
authors.lastname: Withee
authors.forename: Michael
authors.initials: M
authors.lastname: Williams
authors.forename: Terry
authors.initials: T
authors.lastname: Disney
authors.forename: Wayne
authors.initials: W
authors.lastname: Schlosser
authors.forename: Nate
authors.initials: N
authors.lastname: Bauer
authors.forename: Eric
authors.initials: E
authors.lastname: Ebel
mesh_terms: D000465:Algorithms; D000822:Animal Husbandry / Q000191:economics; D000818:Animals; D002417:Cattle; D017281:Cost of Illness; D003362:Cost-Benefit Analysis; D004927:Escherichia coli Infections / Q000191:economics / Q000453:epidemiology / Q000517:prevention & control* / Q000662:veterinary; D019453:Escherichia coli O157 / Q000472:pathogenicity*; D022361:Escherichia coli Vaccines / Q000008:administration & dosage*; D005506:Food Contamination / Q000706:statistics & numerical data; D005516:Food Microbiology; D005523:Food Supply / Q000191:economics; D005517:Foodborne Diseases / Q000191:economics / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D032521:Immunity, Herd; D032541:Mass Vaccination / Q000191:economics / Q000706:statistics & numerical data / Q000662:veterinary*; D015233:Models, Statistical; D018570:Risk Assessment / Q000379:methods*; D014481:United States; D015047:Zoonoses
chemical_list: D022361:Escherichia coli Vaccines