A disease caused by infection with the organism Listeria monocytogenes .
Causes, incidence, and risk factors
Listeria monocytogenes is found commonly in wild animals, domesticated animals, and in soil and water. L. monocytogenes causes disease in many animals and is a common cause of spontaneous abortion and stillbirth in domestic animals. L. monocytogenes also occurs as a food-borne contaminant that can cause disease.
In the human, L. monocytogenes most often causes a generalized blood infection ( septicemia ) or meningitis (inflammation of the covering of the brain). The fetus, newborn, and pregnant women are particularly susceptible to L. monocytogenes. Immunocompromised individuals, such as those being treated for cancer , those with organ transplants, and those with AIDS are at increased risk.
Infection of a pregnant woman early in pregnancy generally leads to spontaneous abortion. The organism may be transmitted across the placenta. Infections in late pregnancy may lead to stillbirth or an infant who dies within a few hours of birth. About half of infants infected at or near term will die.
Listeriosis may become evident in the first few days of life with loss of appetite , lethargy , jaundice , vomiting , respiratory distress, and shock . Infants usually have pneumonia. A skin rash may be present transiently. The death rate is very high.
Late-appearing infection in the infant (symptoms appear at age 5 days or older) and infection in children is often seen as meningitis. There are no special clinical signs to differentiate listerial meningitis from other types of meningitis.
In adults, the disease may take many forms depending on what organ or organ systems are infected. It may occur as meningitis, pneumonia , septicemia, and endocarditis or in milder form as abscesses , skin lesion , and conjunctivitis .
Expectations (prognosis)
Transplacental infection with L. monocytogenes results in a poor outcome with approximately a 50% death rate. The late infant onset form also has a high death rate. Healthy older children and adults have a lower death rate.
Complications
In addition to severe disease, stillbirth, and death as described above, infants who survive listeriosis may suffer long-term neurological damage and delayed development.
Calling your health care provider
Call your health care provider if signs or symptoms of Listeriosis develop in you or your child.
Prevention
Avoidance of contact with wild and domestic animals during pregnancy is advisable. Listeria is well controlled in American food products, but food-associated outbreaks have occured. Pregnant women should avoid consumption of soft cheeses, deli meats, and cold salads from salad bars. Foreign food products such as nonpasteurized soft cheeses have also been implicated in outbreaks of listeriosis. Adequate cooking of foods is always indicated.