Listeriosis is a serious infection caused by eating food contaminated with the bacterium Listeria monocytogenes. It has recently been recognized as an important public health problem in the United States. It is found in soil and water, in raw meats and vegetables, and in processed food that becomes contaminated after processing. Primarily affecting pregnant women, newborns, and adults with weakened immune systems, listeriosis can be avoided by the proper handling and cooking of raw foods. In addition to the threat of the disease itself, the issue of proper governmental inspection of meat processing plants is an important one.