Listeria infection

Listeria infection is a foodborne bacterial illness that can be very serious for pregnant women and people with impaired immune systems. Listeria infection is most commonly contracted by eating improperly processed deli meats and unpasteurized milk products.

Healthy people rarely become ill from listeria infection, but the disease can be fatal to unborn babies and newborns. People who have weakened immune systems also are at higher risk of life-threatening complications. Prompt antibiotic treatment can help curb the effects of listeria infection.

Listeria bacteria can survive refrigeration and even freezing. That's why people who are at higher risk of serious infections should avoid eating the types of food most likely to contain listeria bacteria.

Symptoms Causes Risk factors Complications Prevention

If you develop a listeria infection, you may experience:

  • Fever
  • Muscle aches
  • Nausea
  • Diarrhea

Symptoms may begin a few days after you've eaten contaminated food, but it may take as long as two months before the first signs and symptoms of infection begin.

If the listeria infection spreads to your nervous system, signs and symptoms may include:

  • Headache
  • Stiff neck
  • Confusion or changes in alertness
  • Loss of balance
  • Convulsions

Symptoms during pregnancy and for newborns

During pregnancy, a listeria infection is likely to cause only mild signs and symptoms in the mother. The consequences for the baby, however, may be devastating. The baby may die unexpectedly before birth or experience a life-threatening infection within the first few days after birth.

As in adults, the signs and symptoms of a listeria infection in a newborn can be subtle, but may include:

  • Little interest in feeding
  • Irritability
  • Fever
  • Vomiting

When to see a doctor

If you've eaten a food that's been recalled because of a listeria outbreak, pay close attention to any possible signs or symptoms of illness. If you experience fever, muscle aches, nausea or diarrhea, contact your doctor. The same goes for illness after eating a potentially contaminated product, such as foods made with unpasteurized milk or poorly heated hot dogs or deli meats.

If you experience a high fever, severe headache, stiff neck, confusion or sensitivity to light, seek emergency care. These signs and symptoms may indicate bacterial meningitis, a life-threatening complication of a listeria infection.

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