listeria causes

listeria causes
Causes
By Mayo Clinic staff

Listeria bacteria can be found in soil, water and animal feces. Humans typically are infected by consuming:

Raw vegetables that have been contaminated from the soil or from contaminated manure used as fertilizer
Infected meat
Unpasteurized milk or foods made with unpasteurized milk
Certain processed foods — such as soft cheeses, hot dogs and deli meats that have been contaminated after processing

Unborn babies can contract a listeria infection from the mother via the placenta. Breast-feeding is not considered a potential cause of infection.