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ListeriosisListeriosis, a serious infection caused by eating food contaminated with the bacterium Listeria monocytogenes, is an important public health problem in the United States. Symptoms can show up 1-70 days after exposure to contaminated food and may include vomiting, nausea, cramps, diarrhea, headache, constipation, or fever. Some infections become severe and develop into an infection of the brain or lining of the brain and blood poisoning. Some people experience only mild flu-like symptoms.

While healthy adults and children occasionally get infected with Listeria, they rarely become seriously ill. The disease affects primarily older adults, pregnant women, newborns, and adults with weakened immune systems. Each year in the U.S. about 1,600 persons become seriously ill with listeriosis, and of these, 260 die.


What you can do:
When infection occurs during pregnancy, antibiotics given promptly can often prevent infection of the fetus or newborn. A person in a high-risk category who experiences flu-like symptoms within two months of eating contaminated food should seek medical care and tell the physician or healthcare provider about eating the contaminated food.

  • If a person has eaten food contaminated with Listeria and does not have any symptoms, most experts believe that no tests or treatment are needed, even for persons at high risk for listeriosis.
  • Even with prompt treatment, some infections result in death, particularly in the elderly and in persons with other serious medical problems. Antibiotics used in the treatment of listeriosis include ampicillin, trimethoprim/sulfamethoxazole, meropenem, vancomycin, ciprofloxacin, linezolid, and azithromycin.


The risk of listeriosis can be reduced by following general guidelines for food safety:

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


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