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 animal 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.

Apr. 01, 2014