- Listeriosis is caused by a type of bacteria called Listeria monocytogenes (listeria) and is mainly spread through contaminated food.
- Listeria is widespread throughout the environment and can be found in soil, wood, decaying vegetation and water.
- Unlike most other types of bacteria, listeria can survive and often multiply in temperatures below 5ºC (41ºF). Therefore, listeria can still grow to potentially harmful levels in food stored in a fridge.
- Listeria cannot multiply in temperatures below 0ºC (32ºF), but freezing food doesn't necessarily kill all listeria bacteria.
- Listeria can be removed by cooking food thoroughly or, in the case of dairy products, pasteurising it (a heat treatment designed to kill bacteria).
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