Executive Summary
Each year in the United States, an estimated 9 million people get sick, 56,000 are hospitalized, and 1,300 die of foodborne disease caused by known pathogens. These estimates help us understand the scope of this public health problem. However, to develop effective prevention measures, we need to understand the types of foods contributing to the problem. The Interagency Food Safety Analytics Collaboration (IFSAC) is a tri-agency group created by the Centers for Disease Control and Prevention (CDC), the U.S. Food and Drug Administration (FDA), and the U.S. Department of Agriculture’s Food Safety and Inspection Service (USDA-FSIS). IFSAC developed a method to estimate the percentages of foodborne illness attributed to certain sources using outbreak data from 1998 through the most recent year for IFSAC’s priority pathogens: Salmonella, Escherichia coli O157, Listeria monocytogenes, and Campylobacter. IFSAC described this method and the estimates for 2012 in a report, in a peer-reviewed journal article, and at a public meeting. Unlike in prior IFSAC Annual Reports, attribution estimates for Campylobacter are not presented in this year’s report. Evidence suggests the sources of Campylobacter outbreaks likely differ considerably from the sources of non-outbreak-associated illnesses caused by this pathogen. IFSAC is exploring alternative approaches for estimating the sources ofCampylobacter illnesses.IFSAC derived the estimates for 2020 using the same method used for the previous estimates, with some modifications. The data came from 1,287 foodborne disease outbreaks that occurred from 1998 through 2020 and for which each confirmed or suspected implicated food was assigned to a single food category. The method relies most heavily on the most recent five years of outbreak data (2016 – 2020).
Foods are categorized using a scheme IFSAC created to classify foods into 17 categories that closely align with the U.S. food regulatory agencies’ classification needs.
Salmonella illnesses came from a wide variety of foods. More than 75% of Salmonella illnesses were attributed to seven food categories: Chicken, Fruits, Pork, Seeded Vegetables (such as tomatoes), Other Produce (such as fungi, herbs, nuts, and root vegetables), Beef, and Turkey.
E. coli O157illnesseswere most often linked to Vegetable Row Crops (such as leafy greens) and Beef. More than 80% of illnesses were linked to these two categories.
Listeria monocytogenes illnesses were most often linked to Dairy products, Fruits, and Vegetable Row Crops. More than 75% of illnesses were attributed to these three categories, but the rarity of Listeria monocytogenes outbreaks makes these estimates less reliable than those for other pathogens.
