USDA reports Listeria was top cause of outbreaks it investigated in FY 2025

The USDA’s Food Safety and Inspection Service has released a report on outbreaks it investigated during fiscal year 2025, showing that Listeria monocytogenes was the most frequent cause of outbreaks.

The agency defines an outbreak as an incidence when two or more people experience similar illnesses after eating a common food and epidemiologic analysis implicates the food as the source of the illnesses. 

For fiscal year 2025, the Food Safety and Inspection Service (FSIS) investigated seven foodborne illness outbreaks. The agency has authority over meat, poultry and processed egg products.

The outbreaks investigated by FSIS involved approximately 250 illnesses and 140 hospitalizations. The Centers for Disease Control and Prevention notified FSIS of five of the outbreaks. All seven outbreaks involved illnesses in more than one state.

Of the seven outbreaks investigated by FSIS in FY 2025, one was caused by Salmonella Enteritidis, two by E. coli O157:H7, and four by Listeria monocytogenes. Beef was of interest in two outbreaks, ready-to-eat (RTE) meat and poultry products in one outbreak, multi-ingredient foods in two outbreaks, and multiple products were investigated in two outbreaks in FY 2025.

Three of the seven outbreak investigations conducted in FY 2025 led to a recall by an FSIS-inspected establishment. One Listeria monocytogenes outbreak led to both an initial recall and a public health alert.

“While investigating outbreaks is crucial to protect public health, it is important to note that outbreak-associated illnesses represent a very small proportion of all foodborne illnesses. Consumers who are sick with a foodborne illness may not seek medical care or be tested for foodborne pathogens. Those that are tested may not be linked to other similar illnesses to initiate an outbreak investigation,” according to the FSIS report.

“During FY 2025, FSIS investigated two outbreaks involving multi-ingredient products (e.g., prepared pasta meals containing pasta, sauce, chicken, and other ingredients). These investigations can be extremely complicated and require multi-agency investigations to determine if the source of contamination is an individual ingredient or an issue with the producer of the final product.”

Depending on the evidence collected during an investigation, the FSIS may have enough detailed exposure and product information to take one or more actions to prevent additional illnesses. These actions may include requesting that a company remove product from commerce and FSIS issuing a press release announcing that a firm is recalling products linked to human illnesses or FSIS notifying the public of potential food safety concerns through the issuance of a Public Health Alert.

The FSIS conducts after action reviews at the conclusion of foodborne outbreak investigations to identify lessons learned that can help improve response and prevent future illnesses.