Food Safety News has reported that an outbreak of Listeria monocytogenes infections traced to supplemental shakes served in medical facilities in the United States resulted in 42 people hospitalised and 14 deaths.
The US Food and Drug Administration (FDA) has been investigating the outbreak since November 2024, with infections dating back to 2018. By the end of the outbreak, patients in 21 states had been identified.
The source of the Listeria was traced to Lyons ReadyCare brand and Sysco Imperial brand frozen supplemental shakes manufactured by Prairie Farms from the Prairie Farms Dairy facility in Fort Wayne.
As part of the investigation, the FDA conducted an onsite inspection and collected environmental and product samples at Prairie Farms Dairy Inc. Three of the environmental swabs collected from the processing area tested positive for Listeria monocytogenes. Whole Genome Sequencing analysis determined that the Listeria detected in the samples was the strain of Listeria that caused illnesses in the outbreak.
In response to the outbreak investigation, Lyons Magnus LLC voluntarily recalled 4-ounce Lyons ReadyCare and Sysco Imperial frozen supplemental shakes with best-by dates of 21 February 2025 to 21 February 2026. Read the full story here.
This outbreak is an important reminder for dairy manufacturers about the risks of Listeria monocytogenes – even in frozen product. It highlights the importance of maintaining robust systems and controls, including Good Hygiene Practices and Good Manufacturing Practices, and ensuring cleaning and sanitation programs remain effective and fit for purpose to safeguard food safety.
Listeria monocytogenes is considered the number one food safety hazard in dairy processing. If a lab detects a notifiable contaminant in a food sample, they are obliged to report the finding to SA Health.
Dairysafe also requires immediate notification of any listeria species found in food or the environment, as well as other pathogens found in dairy products. In such cases, contact Dairysafe immediately for assistance and advice on next steps.
You can also refer to the Dairysafe pathogen management flowchart, which outlines appropriate company response arrangements.
There are many resources and reference materials available to guide you in this process. Check out the Food Safety Toolbox on the Dairysafe website.