- Vegetables can become contaminated from the soil or from manure used as fertilizer.
- Animals can carry the bacteria and can contaminate meats and dairy products.
- Processed foods, such as soft cheeses and cold cuts, can be contaminated after processing.
- Unpasteurized (raw) milk or foods made from unpasteurized milk can be contaminated.
Foods that can cause listeria include unpasteurized dairy products and raw or undercooked proteins. For the full list of items pregnant brides should consider not consuming, check out this list.