"S. Typhimurium was detected in three of the 40 brand A product samples collected; isolates were indistinguishable by WGS from the clinical isolates collected from patients in the outbreak. The positive samples included two from bottled raw whole milk collected by CDFA at the bottling facility operated by dairy farm A on October 19 and 25, 2023; one retail sample of raw milk with a best-by date of October 27, 2023. No Salmonella bacteria were detected in the remaining samples from retail stores and patients’ homes. In addition, the outbreak strain was detected in a sample of raw cheese aged for 60 days made from the contaminated milk and collected from the dairy during January 2024; S. Typhimurium was not detected in any raw milk cheese samples collected before January 2024."
"In California, unpasteurized (raw) milk is regulated by the California Department of Food and Agriculture (CDFA). CDFA requires raw milk dairy farms to hold a permit and pass dairy farm and bottling sanitation inspections. Livestock must be tested for brucellosis and tuberculosis annually. Raw milk must meet strict bacterial and cell count limits and be kept at 45°F (7.2°C) or below (1). Raw milk may be legally sold at retail stores but requires warning labels alerting customers of potential contamination by disease-causing microorganisms."
https://www.cdc.gov/mmwr/volumes/74/wr/mm7427a1.htm
Outbreak of Salmonella Typhimurium Infections Linked to Commercially Distributed Raw Milk — California and Four Other States, September 2023–March 2024
Weekly / July 24, 2025 / 74(27);433–438
Eva Weinstein, MPH1; Katherine Lamba, MPH1; Christian Bond1; Vi Peralta, MPH1; Michael Needham, MPH1; Stephen Beam, PhD2; Francine Arroyo, MSc1; David Kiang, PhD1; Yishi Chen, PhD1; Seema Shah, MD3; Mark E. Beatty, MD3; Stephen Klish, MPH4; Akiko Kimura, MD1 (View author affiliations)
Summary
What is already known about this topic?
Unpasteurized (raw) milk has been linked to foodborne illness outbreaks caused by Escherichia coli bacteria and certain species of Brucella, Campylobacter, Cryptosporidium, and Salmonella.