Listeriosis Health Article

Definition

Listeriosis is an illness caused by the bacterium Listeria monocytogenes that is acquired by eating contaminated food. The organism can spread to the blood stream and central nervous system. In women who contract listeriosis while pregnant, the disease often causes miscarriage or stillbirth.

Description

Listeriosis is caused by an infection with the bacterium Listeria monocytogenes. These bacteria can be carried by many animals and birds, and they have been found in soil, water, sewage, and animal feed. Five out of every 100 people carry Listeria monocytogenes in their intestines. Listeriosis is considered a food-borne illness because most people are probably infected after eating food contaminated with Listeria monocytogenes. However, a woman can pass the bacteria to her baby during pregnancy. In addition, there have been a few cases where workers have developed Listeria skin infections by touching infected calves or poultry.

In the 1980s, the United States government began taking measures to decrease the occurrence of listeriosis. Subsequently, processed meats and dairy products were tested for the presence of Listeria monocytogenes. The Food and Drug Administration (FDA) and the Food Safety and Inspection Service (FSIS) can legally prevent food from being shipped, or order food recalls, if they detect any Listeria bacteria. These inspections, in combination with the public education regarding the proper handling of uncooked foods, appear to be helping. Nonetheless, as of 2004, about 2,500 individuals become seriously ill from Listeria annually, with about 500 deaths.

Demographics

Persons at particular risk for listeriosis include the elderly, pregnant women, newborns, and those with a weakened immune system (called immunocompromised). Risk is increased when a person suffers from diseases such as AIDS, cancer, kidney disease, diabetes mellitus, or by the use of certain medications. Infection is most common in babies younger than one month old and adults over 60 years of age. Pregnant women account for 27 percent of the cases, and immunocompromised persons account for almost 70 percent. Persons with AIDS are 280 times more likely to get listeriosis than others.