Listeria (Listeriosis) Topic Guide

Food poisoning is caused by viruses, bacteria, toxins, parasites, or chemicals that have contaminated food or drinking water. Symptoms of food poisoning include diarrhea, vomiting, nausea, fever, abdominal cramping, dehydration, rectal bleeding, and bloating. Food poisoning usually can be cared for at home. In some instances (severe dehydration) a person may be hospitalized for treatment.

The first symptoms and signs of Listeria (listeriosis) can start within a few days after eating contaminated food, but the incubation period for Listeria can be long and symptoms may develop one month or more after ingestion. Symptoms of Listeria can come on suddenly and some of the first signs of Listeria may include fever, muscle aches, severe headache, nausea, vomiting, stiff neck, confusion, loss of balance, and convulsions. Symptoms of Listeria may vary depending on which part of the body is affected. Listeria may also cause serious complications in pregnant women.

Foods that have a risk of listeria include raw (unpasteurized) milk, soft and semi-soft cheeses, hot dogs, deli meats, ready-to-eat meals, foods at salad bars/sandwich bars/delicatessens, refrigerated pâtés or meat spreads, refrigerated smoked seafood, unwashed raw fruits and vegetables, soft-serve ice cream, and raw shellfish and seafood.

Listeria (listeriosis) is a potentially serious infection usually caused by eating food contaminated with the bacterium Listeria monocytogenes. Symptoms include nausea and vomiting, among others. It is usually not serious in otherwise healthy people.