infectious diseases
Listeriosis
Transmission
BecauseL. monocytogenesis ubiquitous in the environment, opportunities for contamination are numerous during the food production process. Nearly all types of food can harbor and transmitL. monocytogenes, but infection usually occurs via ingestion of contaminated dairy products, raw vegetables, meats, or, particularly, refrigerated foods that require no cooking before they are eaten. Contamination is favored by the ability ofL. monocytogenesto survive and grow at refrigerator temperatures. Infection may also occur by direct contact with and during slaughter of infected animals. Listeria monocytogenescan reproduce at refrigerator temperatures, so lightly contaminated refrigerated food can become heavily contaminated. 