Foodborne Illness – Listeriosis

Listeriosis is a serious infection caused by eating food contaminated with the bacterium Listeria monocytogenes. The disease affects primarily pregnant women, newborns, and adults with weakened immune systems. It can be avoided by following a few simple recommendations.

Symptoms

• Fever, muscle aches, and sometimes gastrointestinal symptoms such as nausea or diarrhea.
• If infection spreads to the nervous system, symptoms such as headache, stiff neck, confusion, loss of balance, or convulsions can occur.
• Infected pregnant women may experience only a mild, flu-like illness; however, infections during pregnancy can lead to premature delivery, infection of the newborn or even stillbirth.

How It Is Spread

• Listeria monocytogenes is commonly found in soil and water.
• The bacterium has been found in a variety of raw foods, such as uncooked meats and vegetables, as well as in processed foods that become contaminated after processing, such as soft cheeses and cold cuts at the deli counter.
• Unpasteurized (raw) milk or foods made from unpasteurized milk may contain the bacterium.
• Eating food contaminated with Listeria.
• Babies can be born with listeriosis if their mothers have eaten contaminated food during pregnancy.

Diagnosis & Treatment

• If you have symptoms such as fever or stiff neck, consult your doctor. A blood or spinal fluid test (to cultivate the bacteria) will show if you have listeriosis.
• During pregnancy, a blood test is the most reliable way to find out if your symptoms are due to listeriosis.
• When infection occurs during pregnancy, antibiotics given promptly can often prevent infection of the fetus or newborn. Babies with listeriosis receive the same antibiotics as adults,
• Even with prompt treatment, some infections result in death. Serious infections are more likely in the elderly and in persons with other serious medical problems.

Prevention

• Thoroughly cook raw food from animal sources, such as beef, pork, or poultry.
• Wash raw vegetables thoroughly before eating.
• Keep uncooked meats separate from vegetables, cooked foods, and ready-to-eat foods.
• Avoid raw (unpasteurized) milk or foods made from raw milk.
• Wash hands after handling uncooked foods.
• Wash, rinse, and sanitize knives and cutting boards that contact uncooked foods.

Additional recommendations for persons at high risk, such as pregnant women and persons with weakened immune systems:

• Avoid soft cheeses such as feta, Brie, Camembert, blue-veined, and Mexican-style cheese. Hard cheeses, processed cheeses, cream cheese, cottage cheese, or yogurt need not be avoided.
• Left-over foods or ready-to-eat foods, such as hot dogs, should be cooked until at least 165°F before eating.
• Although the risk of listeriosis associated with cold cuts is relatively low, pregnant women and immunosupressed persons may choose to avoid these foods or thoroughly reheat before eating.