Listeria (Liss-TEE-ree-uh mah-no-si-TAH-juh-nees) is a disease that most people are not familiar with. Yet, it is one of the biggest killers from foodborne illness in the U.S. There are two forms of the illness, one which is milder and usually goes away on its own. The other is much more dangerous, as it spreads through the bloodstream to the nervous system, where it can result in meningitis or death. Listeria is by far most dangerous to pregnant women, where it can cause miscarriage, stillbirth, or illness to the baby if it survives. The mothers usually experience illness as well. Other groups who are affected by Listeria include immunocompromised people (weakened immune systems) and the elderly. Occasionally even healthy people can contract Listeria.
The milder form of Listeria can cause nausea, vomiting, aches and fever, and can take a day or two to show up. The more dangerous form usually has a much longer incubation time, from 3 days to 3 months! With this form of the disease, it spreads throughout the body and can turn into meningitis.
The difficulty with this bacteria is how tough it is. It can survive salty environments, unlike a lot of other bacteria, and it can actually survive refrigeration temperatures very well. Listeria has commonly been traced back to raw or unpasteurized milk and cheeses, smoked fish, deli meats and cheeses, hot dogs, and even raw vegetables.
You can prevent Listeria infection by washing your hands and keeping cooking surfaces clean, separating raw and cooked foods, cook food according to instructions, and avoid unpasteurized dairy products. Pregnant women should take special care to avoid certain foods like soft cheeses and deli foods, unless they have taken extremely good precautions to prepare them, such as cooking the food to high temperatures.
If you would like to read about some illness outbreaks that were caused by Listeria, you can read about them on this site: http://www.about-listeria.com/listeria_outbreaks/#.WML0IXoszsY