ABSTRACT
Listeria monocytogenes is a peritrichously agellated, gram-positive, intracellular bacterial pathogen that is capable of growth at refrigerator temperatures. The organism has a wide host range including mammals, birds, sh, and crustacea (Davis et al., 1973) and is widely distributed, being found in plant, soil, and surface water samples (Weiss and Seeliger, 1975). The organism has been isolated from a wide variety of foods, including milk, cheese, coleslaw, frankfurters, beef, poultry, and sh (Lovett, 1989) and is capable of growth at refrigerator temperatures as low as 1°C (Seeliger and Jones, 1986). Most healthy adults infected with L. monocytogenes experience only mild u-like symptoms (Lovett, 1989). Listeriosis, however, is an infectious disease, which is characterized by monocytosis, growth of the organism in macrophages, septicemia, and the formation of multiple focal abscesses in the viscera. Infection of pregnant women may lead to invasion of the fetus, resulting in stillbirth or abortion (Lovett, 1989). The commonest form of listeriosis is meningitis, which develops predominantly in newborns and the aged, resulting in approximately 70% mortality if untreated (Seeliger and Finger, 1976; Killinger, 1970).
