A multistate Listeria monocytogenes outbreak that has been sickening people since 2018, 12 of them fatally, has now been tied to frozen supplement shakes consumed mainly at long-term care facilities, federal health officials said yesterday.
In a food safety alert, the Centers for Disease Control and Prevention (CDC) said 38 cases from 21 states have been reported. All but 1 patient was hospitalized.
Listeria infections can be severe or fatal, especially in pregnant women, people ages 65 and older, and those with weakened immune systems.
Earlier probes didn't turn up specific source
Though illnesses have been reported since 2018 and earlier epidemiologic investigations suggested that food served at the institutions was a likely source, there wasn't enough evidence to pinpoint a specific food source.
Following investigations in 2018, 2021, and 2023, the CDC reopened the investigation in October 2024 after six new infections were reported. In background information on the outbreak, the Food and Drug Administration (FDA) said 20 of the cases were reported in 2024 and 2025 and that the outbreak and the investigations are ongoing.
State and local health officials who interviewed sick patients found that 34 were in nursing homes or hospitals before they became ill and that 8 were on soft diets. A review of facility records showed that the supplement shakes were available to the patients.
Patient ages range from 43 to 101 years old, with a median age of 78. People who died from their infections were from California, Illinois, Indiana, Michigan, Minnesota, North Carolina, New York, Tennessee, Texas, and Washington.
Key clues from product trace-back, environmental sampling
In November 2024, the FDA said it learned that many of the sick people lived in nursing homes. Its trace-back investigation found that found that all of the nursing homes that provided food invoices since 2024 had received frozen supplement shakes from Lyons ReadyCare or Sysco Imperial brand.
FDA investigators collected environmental samples at the Prairie Farms Dairy facility that made the shakes, which were positive for the outbreak strain. Whole-genome sequencing found that bacteria from the environmental samples were closely related to isolates from sick patients.
On February 22, Lyons Magnus, a distributor based in Fresno, California, recalled 4-ounce servings of several flavors of Lyons ReadyCare and Sysco Imperial Frozen supplemental shakes.
In the company's voluntary recall notice, it said the products were made at the Prairie Farms Dairy facility in Fort Wayne, Indiana. The products were distributed throughout the United States but were not available for retail purchase.
