Listeria monocytogenes (Listeria) is a foodborne illness-causing microorganism that is found naturally in the environment, including soil and water.
Why is it a concern for food safety?
Listeria can contaminate produce, dairy, meat, poultry and other farm products. Once a kitchen, packing house or food processing plant becomes contaminated with Listeria, it can easily spread to different types of foods that pass through. Listeria is commonly found on floor drains, deli meat slicing equipment and in sinks. It can also survive and grow in refrigerated temperatures.
Foods at high risk for Listeria
- Raw (unpasteurized) fruit or vegetable juice
- Raw (unpasteurized) dairy products
- Milk
- Cheeses
- Ice cream
- Ready-to-eat foods not typically heated before being eaten
- Certain fruits and vegetables
- Deli-meats
- Cold cuts
- Sliced cheeses
- Pasta salad
Symptoms
Listeriosis is the foodborne illness caused by Listeria. Symptoms may include:
- Stiff neck
- Nausea
- Vomiting
- Diarrhea
- Headache
- Chills
- Fever
Depending on the individual, symptoms may begin 12 hours or up to 3 weeks after eating contaminated food. In pregnant individuals, Listeriosis typically causes flu-like symptoms like fever and chills, but can also cause serious pregnancy complications.
How to reduce your risk
Listeria is heat-sensitive and can be eliminated through pasteurizing or heat-treating foods by doing the following:
- Cook raw food from animal sources to the correct temperature.
- For meat, such as beef, lamb, pork or goat:
- Cook whole cuts to 145 degrees F, with a rest time of 3 minutes.
- Cook ground meat to 160 degrees F.
- For poultry, such as chicken, turkey or duck:
- Cook whole cuts or ground meat to 165 degrees F.
- For meat, such as beef, lamb, pork or goat:
- Store raw food from animal sources separately from vegetables, cooked foods and ready-to-eat foods.
- Do not consume raw (unpasteurized) milk or foods made from unpasteurized milk.
- Cheeses that may be unpasteurized include:
- Feta
- Brie
- Camembert
- Queso fresco
- Queso blanco
- Always check the label to verify pasteurization status.
- Cheeses that may be unpasteurized include:
- Wash your hands, knives and cutting boards often, especially after handling uncooked foods.
Extra safety for high-risk populations
The very young, those over 65 years old, pregnant and immunocompromised individuals are all high-risk populations who should take extra precautions to reduce the risk of Listeriosis.
In addition to precautions listed above, high-risk populations should also:
- Avoid getting fluid from unheated ready-to-eat foods on other foods, utensils and food preparation surfaces.
- Wash hands after handling unheated ready-to-eat foods.
- Do not consume the following foods:
- Raw (unpasteurized) fruit or vegetable juice.
- Unheated ready-to-eat foods. Although read-to-eat foods were previously cooked, they should be reheated until steaming hot at 165 degrees F. This includes:
- Hot dogs
- Luncheon meats
- Deli meats
- Pasta salad
- Refrigerated pâtés or meat spreads. Canned or shelf-stable pâtés and meat spreads may be eaten.
- Refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole.
- Canned or shelf-stable smoked seafood may be eaten
- Refrigerated smoked seafood such as salmon, trout, whitefish, cod, tuna or mackerel, often found in the refrigerator section or sold at deli counters of grocery stores and delicatessens. These are most often labeled as:
- Nova-style
- Lox
- Kippered
- Smoked
- Jerky
When to report a foodborne illness in Minnesota
If you believe that you became sick from eating any food or beverage, alert the Minnesota Department of Health:
- Call 1-877-FOOD-ILL (1-877-366-3455)
- Submit your report using the confidential Foodborne and Waterborne Illness Report
- Or, email [email protected]
Reviewed in 2025