Listeria monocytogenes has been the cause of countless food recalls, but how does this potentially fatal bacteria infect our foods in the first place?
According to the Centers for Disease Control and Prevention (CDC), Listeria can be found naturally in both soil and water where wild animals can easily transfer it without showing immediate signs of carrying. Listeria can then transfer to raw ingredients or produce that have come into contact with contaminated soil or animal manure that has been used as a fertilizer.
Once the Listeria-infected ingredient reaches a food processing factory, the bacterium may live for years on equipment without being noticed. Listeria is infamous for its ability to survive in colder temperatures of refrigerators and freezers, unlike many other forms of bacteria.
“It’s a pathogen that’s particularly problematic in food-processing plants because it really likes cold, moist, dark environments,” Benjamin Chapman, a food safety expert at North Carolina State University in Raleigh, told Live Science in a 2015 interview. Chapman also says that Listeria outbreaks have been linked to foods such as raw milk, unpasteurized soft cheeses and even deli meats.
Listeriosis, the illness that can be triggered by eating food contaminated with Listeria, can result in nausea, vomiting, diarrhea, cramps, fever, body aches, and other flu-like symptoms. The illness is particularly deadly to young children, the elderly, and people with weak immune systems. Infection during pregnancy can lead to miscarriage, stillbirth, premature delivery, and severe, life-threatening infections in newborns.
Reducing your risk of a Listeria infection is simple and the CDC recommends the following tips to ensure your food is safe for consumption:
- “Rinse raw produce, including fruits and vegetables, before eating, cutting or cooking;
- Use a produce brush to scrub firm vegetables, such as melons and cucumbers;
- Dry produce with a clean cloth or paper towel;
- When preparing food, separate uncooked meats from vegetables and cooked foods;
- When you handle uncooked foods, be sure to wash your hands afterward, as well as the knives and cutting boards you used for the foods;
- Do not drink unpasteurized milk;
- Heat ready-to-eat foods and leftovers until they are steaming hot;
- People at higher risk of infection, such as pregnant women, should not eat hot dogs, luncheon meats, cold cuts or other deli meats unless they are heated to an internal temperature of 165 degrees Fahrenheit (74 degrees Celsius). They should also avoid eating soft cheeses, unless the label says it’s made with pasteurized milk.”