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- Listeriosis (Listeria monocytogenes infection) facts
- What is listeriosis? What causes listeriosis?
- What are listeriosis symptoms and signs?
- What are the risk factors for listeriosis?
- How is listeriosis diagnosed?
- What is the treatment for listeriosis?
- How does a person get listeriosis?
- Can listeriosis be prevented?
- What is the prognosis (outcome) for Listeria infections?
- If a person has eaten recalled food potentially contaminated with Listeria, what should he or she do?
- What is the government doing about listeriosis?
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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 unpasteurized 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 much 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. Most individuals who get severe infections and/or die from listeriosis have one or more of the medical problems listed above.
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 reliable serological tests available (blood tests that can identify specific proteins associated with the bacteria or antibodies to the bacteria) according to the CDC.