Listeria

A group of bacteria capable of causing miscarriage (spontaneous abortion), stillbirth and premature birth and which can also cause serious and sometimes fatal infections in young children, frail or elderly people, and persons with a weakened immune system. Contamination with listeria has been responsible for numerous recalls of food. For example, it led to a milk recall in February, 1999. Kohler Mix Specialties, Inc., a White Bear Lake, Minnesota-based subsidiary of Michael Foods, Inc., recalled milk produced and sold under the Land O' Lakes brand name. The recall was due to possible contamination of the milk with Listeria monocytogenes. In April 2000 the entire genome of Listeria was sequenced by a consortium of European scientists in 10 laboratories and companies coordinated by the Institute Pasteur in Paris. This could hopefully lead to a vaccine against Listeria. In January 2001 US makers of hot dogs, deli meats and other ready-to-eat meat and poultry were ordered by the government to begin testing their products to detect and prevent Listeria contamination. Listeria are named after the English surgeon and apostle of antisepsis, Joseph Lister (1827-1912). Disease caused by listeria bacteria is called listeriosis.

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A genus of aerobic to microaerophilic, motile, peritrichous bacteria containing small, coccoid, Gram-positive rods; these organisms tend to produce chains of 3–5 cells and, in the rough state, elongated and filamentous forms. Cells 18–24 hours old may show a palisade arrangement with a few V or Y forms; the bacteria produce acid but no gas from glucose and are found in the feces of humans and other animals, on vegetation, and in silage and are parasitic on poikilothermic and warm-blooded animals, including humans. The type species is L. monocytogenes. [Joseph Lister]

- L. denitrificans a bacterial species reclassified as Jonesia denitrificans.

- L. grayi a bacterial species found in the feces of chinchillas.

- L. monocytogenes a bacterial species causing meningitis, encephalitis, septicemia, endocarditis, abortion, abscesses, and local purulent lesions; it is often fatal; it is found in healthy ferrets, insects, and the feces of chinchillas, ruminants, and humans, as well as in sewage, decaying vegetation, silage, soil, and fertilizer. Sometimes involved in infections in immunocompromised hosts. A causative agent of perinatal infections, neonatal sepsis and septicemia. Also recently linked to food-borne diseases especially associated with meat and dairy products.

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lis·te·ria lis-'tir-ē-ə n

1) cap a genus of small gram-positive flagellated rod-shaped bacteria that do not form spores, are aerobic or facultatively anaerobic, and have a tendency to grow in chains and that include one (L. monocytogenes) causing listeriosis

2) any bacterium of the genus Listeria called also listerella

lis·te·ri·al lis-'tir-ē-əl adj

lis·te·ric -ik adj

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n.

a genus of Gram-positive aerobic motile rodlike bacteria that are parasites of warm-blooded animals. The single species, L. monocytogenes, infects many domestic and wild animals. If it is transmitted to humans, by eating infected animals or animal products, it may cause disease (listeriosis), especially in the frail, ranging from influenza-like symptoms to meningoencephalitis. In pregnant women it may terminate the pregnancy or damage the fetus.

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Lis·te·ria (lis-teґre-ə) [Baron Joseph Lister] a genus of bacteria of the family Listeriaceae, made up of small, coccoid, gram-positive rods that have a tendency to form chains and palisades; they are found in animal feces, on vegetation, and in silage. The type species is L. monocytoґgenes.