Background & History
Foodborne illnesses are caused by ingesting bacteria, fungi, parasites, viruses, toxins, or other harmful substances in contaminated food. Knowing the costs of foodborne illness helps policymakers assess risks, focus policy, and prioritize spending. Some of the first economic estimates of the costs of foodborne illness were provided by ERS.
- conduct economic analyses of the benefits of improved food safety,
- refine estimation methodologies, and
- provide updated estimates of the costs of illness for selected foodborne pathogens.
History of ERS Cost Estimates
ERS researchers conducted some of the earliest studies on the economic costs of foodborne illness and have since updated and expanded these analyses using improved estimation methods and better data. Each series of ERS estimates has incorporated better information on disease incidence, more detailed data on the health consequences of foodborne illness, and advances in the economic methodologies for valuing health outcomes.
ERS published its first comprehensive cost estimates for 16 foodborne bacterial pathogens in 1989 in the American Journal of Agricultural Economics (see Roberts, Tanya, "Human Illness Costs of Foodborne Bacteria," American Journal of Agricultural Economics, 71(2):468-74, May 1989). These initial estimates reflected the limited information then available about the incidence of foodborne illness, and used cost-of-illness (COI) methodology to tally expenditures on medical care and lost productivity due to nonfatal illness and premature death.
In 1996, ERS updated the cost estimates for:
- six bacterial pathogens (Campylobacter, Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella, and Staphylococcus aureus) in a report, Bacterial Foodborne Disease: Medical Costs and Productivity Losses
- one foodborne parasite (toxoplasma gondii): see "ERS Updates U.S. Foodborne Disease Costs for Seven Pathogens". ERS continued to use the COI methodology for nonfatal illnesses, but adopted two different health valuation methodologies for premature deaths: the individualized human capital approach and the willingness-to-pay (WTP) approach.
In 2000, ERS used new Center for Disease Control and Prevention (CDC) disease incidence estimates by Paul S. Mead and co-authors (see "Food-Related Illness and Death in the United States," Emerging Infectious Diseases) to update the cost of illness estimates for four pathogens (Campylobacter, Salmonella, E. coli O157:H7, and Listeria monocytogenes). See "Food Safety Efforts Accelerate in the 1990’s":
- The COI methodology was used for nonfatal illnesses, and the WTP approach was used for premature deaths. The WTP approach used in these estimates and the 2004 estimates for E. coli O157:H7 annuitizes the value of statistical life (VSL) estimates and uses the VSL to value reduced life expectancy.
- The Salmonella cost estimate was prepared in collaboration with CDC's FoodNet Foodborne Diseases Active Surveillance Network, and used new sources of data on medical costs and productivity losses, including FoodNet surveillance data and a large commercial medical claims database. (See "Salmonella Cost Estimates Updated Using FoodNet Data").
The cost estimate for E. coli O157:H7 (now termed STEC O157) was subsequently updated in collaboration with FoodNet in 2005, using FoodNet surveillance data and a case-control study of STEC O157 patients (see "Economic cost of illness due to Escherichia coli O157 infections in the United States"). This report provides a detailed description of the methods used for the E. coli O157:H7 cost of illness.
In 2003, ERS introduced the Foodborne Illness Cost Calculator, an interactive online version of the updated ERS cost estimates for selected foodborne pathogens. The Cost Calculator initially included the Salmonella cost estimate, and later added the 2005 STEC O157 estimate. The Cost Calculator provided detailed information about the assumptions underlying each estimate, and allowed users to make alternative assumptions and re-estimate the costs.
In 2014, ERS replaced the Cost Calculator with the new Cost Estimates of Foodborne Illnesses data product. This data product added cost estimates for 11 pathogens to those already included in the ERS Cost Calculator based on research published by Hoffmann and coauthors (see Hoffmann, Sandra, Michael B. Batz, and J. Glenn Morris, Jr., "Annual Cost of Illness and Quality-Adjusted Life Year Losses in the United States Due to 14 Foodborne Pathogens," Journal of Food Protection 75(7): 1291-1302, January 2012). The 2014 estimates are based on CDC’s 2011 foodborne disease incidence estimates by Elaine Scallan and co-authors (see "Food-Related Illness Acquired in the United States—Major Pathogens" in Emerging Infectious Diseases).
The documentation section of the Cost Estimates of Foodborne Illnesses data product provides a full explanation of the methods used. These estimates follow the U.S. Environmental Protection Agency on the use of the VSL and do not annuitize the VSL. The rational for this shift in method is described in Making Sense of Recent Cost-of-Illness Estimates. A companion report, Economic Burden of Major Foodborne Illnesses Acquired in the United States, provides pathogen-specific graphics and disease descriptions designed to help inform food safety education efforts. The documentation section also includes instructions for updating estimates annually for price inflation and real income growth.