Listeriosis

Most people who ingest listeria will be asymptomatic or have mild symptoms of nausea, fever, muscle aches and diarrhea. However, some people can develop an invasive infection. Symptoms of invasive listeriosis may start 2 and 4 weeks or as many as 70 days after eating or drinking a product contaminated with the bacteria. Invasive listeriosis can be fatal in 20% of people. If the disease progresses to infection of the brain and spinal cord (meningoencephalitis), it can produce delirium, shock, and coma.

Infected pregnant women may have only a mild, flu-like illness, but infections during pregnancy can cause miscarriage, stillbirth, premature delivery, or illness in the newborn.

L. monocytogenes is found in soil and water. Vegetables can become contaminated from the soil or from manure used as fertilizer. Animals can also carry the bacteria without seeming ill, and can cause contamination of foods such as meats and dairy products.

You can get listeriosis by drinking or eating raw (unpasteurized) milk or milk products–especially soft cheeses– or from consuming contaminated raw vegetables and fruits. The bacteria are sometimes found in ready-to-eat meat products. You can also get it through direct exposure to the feces and fetuses from infected animals.

A pregnant woman infected with the bacteria can transmit the disease to her unborn child. This can result in the death of the fetus, premature birth of the child, or infection of the child after it is born.

Your doctor can order a test to isolate the bacteria from a normally sterile site, such as blood or amniotic fluid (for pregnant women). Stool culture for diagnosis is not recommended.

A doctor can prescribe antibiotics to treat listeriosis. When a pregnant woman becomes infected, antibiotic needs to be given right away to prevent infection in the fetus or newborn.