Listeria, << lihs TIHR ee uh, >> are a kind of bacteria that can cause food poisoning in human beings. The organism’s full scientific name is Listeria monocytogenes. Illness caused by the bacteria is called listeriosis. Most outbreaks of listeriosis occur when people eat precooked products, such as hot dogs or cold cuts, that have been contaminated after processing. Pregnant women, older adults, and people with weakened immune systems can become seriously ill by eating foods contaminated with Listeria. Health officials recommend that people who are at risk from listeriosis avoid certain foods and only eat meat products that are thoroughly cooked.
Listeriosis is characterized by mild flulike symptoms, such as fever, chills, and occasionally nausea or diarrhea. If the bacteria spread to the nervous system, headache, neck stiffness, loss of balance, or convulsions can occur. During pregnancy, Listeria can be transmitted from the mother to the fetus and cause miscarriage (premature birth) or other serious health problems for newborn babies. Most deaths from listeriosis occur among fetuses and newborn babies.
Listeria are common bacteria often found in soil and water. Farm animals can carry Listeria in their intestines without becoming sick and can contaminate meat and dairy products. Vegetable crops can be contaminated if manure from infected animals is used as fertilizer. Listeria can survive and grow in refrigerators, where they may contaminate leftover cooked foods. The bacteria are killed by heat and thorough cooking.
