where does listeria come from

Listeria bacteria come from the environment and animals. They are commonly found in soil, water, sewage, and rotting vegetation. The bacteria can contaminate a variety of foods, including raw vegetables, fruits, meat, seafood, fish, dairy products such as milk and cheese, and processed foods. Contamination often occurs through contact with contaminated soil or water, manure-based fertilizers used on crops, or from animals carrying the bacteria in their intestines without showing symptoms. Food processing environments can also become contaminated if good sanitation practices are not followed. Listeria can survive and grow even in refrigerated conditions, which makes it a risk in ready-to-eat chilled foods like deli meats, soft cheeses, and pre- prepared salads. People generally get listeriosis by consuming food contaminated with Listeria bacteria. Farmers, veterinarians, and others in contact with farm animals during birth or butchering can also get infected from animals carrying the bacteria.