Pregnant women, fetuses and newborn infants are among those most susceptible to listeria. Individuals with HIV, AIDS, cancer and other underlying illnesses or conditions which have weakened the immune system are also at risk for infection. Elderly people are also more likely to contract listeria than the rest of the population.
Listeria monocytogenes, also known as listeriosis and most commonly referred to simply as listeria, can affect anybody at any age, but most commonly affects those with compromised immune systems. In most instances, infection makes a person very ill, but many recover with antibiotic treatment. A number of people infected with listeriosis, however, never recover and eventually die from the infection.
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As a bacterium found in soil and water, listeriosis eventually enters foods that are exposed to these infected elements. It then enters the body when these foods are eaten. While listeriosis is found in raw or undercooked foods, it can also be found in cooked foods once infected sources are allowed to naturally cool after cooking or have been cooled by refrigeration. Newborns can also be infected with listeriosis at birth if the mother suffered from infection during pregnancy.
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The symptoms of listeria include extreme gastrointestinal discomfort, body aches, fever and headache. Symptoms may also include a stiff neck, mental confusion, seizures and dizziness. In pregnant women, listeriosis may cause miscarriage or still birth. While infection may cause discomforting symptoms in pregnant women — and many women survive the illness with proper medical treatment — it unfortunately has a devastating effect on unborn children, as many do not survive it even with timely medical intervention. In addition to the common symptoms found in other patients, some of the symptoms present in neonatal infections include respiratory distress, meningitis, sepsis and jaundice.
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When infected individuals receive medical treatment for listeria at its earliest onset, many survive the illness and experience a full recovery. Those who do not receive listeriosis treatment, however, experience a worsening of symptoms and eventually die from the infection. Even with aggressive treatment for listeriosis, however, individuals with previous weakened immune systems are at risk of death.
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Suspected cases of listeria are medically diagnosed after blood or spinal fluid testing. Doctors then commonly prescribe intravenous listeria monocytogenes treatment in an effort to aggressively kill the bacteria in a person’s body. Antibiotics, such as penicillin and amoxicillin, are among those most often used to battle a listeriosis infection.