Listeria (cont.)

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What are the risk factors for listeriosis?

The major risk factor for getting listeriosis is eating or drinking foods and liquids contaminated with Listeria bacteria. Foods and liquids that have been contaminated with animal feces or soil are the most frequently identified sources for these organisms. Drinking inadequately treated or non-pasteurized liquids is another source of infection.

Some individuals have an increased risk for getting listeriosis. In general, people with an altered or damaged immune system have a higher risk of getting listeriosis and its more severe complications. Specifically, people at higher risk include pregnant females, newborns, the elderly, diabetics, cancer patients, AIDS patients, patients with kidney diseases, alcoholics, and those patients undergoing any immune-suppression therapy.

How is listeriosis diagnosed?

Preliminary diagnosis is usually based on the patient's history and physical exam, especially after the patient gives a history of likely exposure to a contaminated food source during a Listeria outbreak. Without this information, the diagnosis is difficult to sort out from many other diseases; this situation may result in a delay of treatment as the physician may do other tests to rule out other diseases such as salmonellosis, shigellosis, botulism and E. coli infections. Definitive diagnosis of listeriosis is by culturing Listeria monocytogenes bacteria from the patient's blood, cerebrospinal fluid, or amniotic fluid, usually on a medium that is selective for Listeria (for example, RAPID'L mono agar). Currently, no reliable tests are available to detect the bacteria in the stool; also, there are no serological tests available (blood tests that can identify specific proteins associated with the bacteria or antibodies to the bacteria).

Medically Reviewed by a Doctor on 12/4/2014

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Listeriosis - Causes Question: Please discuss your experience with listeriosis, including a possible cause.
Listeriosis - Symptoms Question: Were you or someone you know diagnosed with listeriosis? What were the signs and symptoms?
Listeriosis - Treatment Question: What was the treatment for a diagnosed case of listeriosis in you, a friend, or relative?
Listeriosis - Recalled Food Question: Did you ever eat a food that was recalled due to potential Listeria contamination? Please discuss your experience.