Listeria monocytogenes is a ubiquitous pathogen with a high mortality rate that can become persistent in the retail food environment, says Janet Buffer, MPH, of the Center for Foodborne Illness Research and Prevention, Ohio State University. During her presentation “Listeria monocytogenes and sanitation in the retail environment,” at the “Food Safety Hazards Series” virtual event, she discussed areas in retail food service environments most likely to harbor the pathogen as well as the best-proven methods to reduce the prevalence of listeria in your facility.

View the full “Food Safety Tech Hazards Series: Listeria” virtual conference on demand.

Areas that are more likely to harbor listeria monocytogenes in the retail food environment include:

• Cracks and crevices in the floor
• The floor/wall juncture, especially under sinks
• On touchpoints of cooler handles and deli slicers
• In front of deep fryers
• In front of deli slicers and on slicer blades
• Drains
• Sink interiors
• Areas where raw chicken is stored or transported

“Listeria monocytogenes is hardy. It tolerates salt, grows in cold environments and is moderately resistant to acids,” said Buffer. “It is also ubiquitous. We find it in soil, water, silage, manure and sewage. We bring it in on our shoes. We can carry it on our clothes, and it can become a persistent pathogen in our retail spaces.”

A recent study by Briana C. Britton, et al, published in Food Control Journal, identified the most effective sanitation and customer service strategies correlated with lower listeria prevalence in retail delicatessens. These include:

• When the deli is cleaned two-to-three hours/day
• Changing gloves after touching nonfood surfaces
• Keeping sanitation records
• Using foam to clean and sanitize

“All chemicals work and all work very well,” said Buffer. “But, they must be used at the correct concentrations and they will require some elbow grease.”