By Ethan Covey
A widespread outbreak of Salmonella typhimurium, which caused illnesses in five states, was linked to commercially distributed raw milk (MMWR Morb Mortal Wkly Rep 2025;74:433-438).
The outbreak began in October 2023 and lasted until March 2024. While 98% of the 171 cases were in California, single cases were identified in New Mexico, Pennsylvania, Texas and Washington.
Most (70%) of cases occurred in children who were younger than 18 years old, and the median age of those affected was 7 years; 39% of cases occurred in children younger than 5 years old. Among a total of 159 patients confirmed to be infected with the outbreak strain, 70% who had exposure data reported having consumed a particular brand of raw milk or heavy cream from one dairy farm, which voluntarily recalled raw milk and raw heavy cream one week after the initial outbreak identification. The farm and the brands were not named in the report.
“This was one of the largest foodborne outbreaks linked to raw (unpasteurized) milk in recent U.S. history,” said Eva Weinstein, MPH, a health data and geospatial analyst with the California Department of Public Health.“Consumers may think that raw dairy products legally sold at retail stores are safe, but these products can contain harmful bacteria that can cause serious illness. Cheese made from raw milk, even after 60-day aging, may remain contaminated with bacteria such as Salmonella.”
Ms. Weinstein noted the best way to prevent illness from raw milk is to choose pasteurized dairy products, and she encouraged healthcare professionals to communicate the risks associated with raw dairy products to patients, particularly those who may be at high risk for infection.
“Clinicians should remind their patients of the health risks associated with consuming raw dairy products, even those legally sold and labeled, and encourage choosing pasteurized dairy products,” she said. “Raw milk can expose people to multiple harmful infectious pathogens including Salmonella, Campylobacter, Listeria and Shiga toxin-producing Escherichia coli. Children younger than age 5, pregnant persons, adults older than 65 and people with weakened immune systems are more likely to get sick from bacteria in raw dairy products.”
Ms. Weinstein reported no relevant financial disclosures.
