- 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).
More top news
David Cameron and Jeremy Corbyn have dramatically clashed in the House of Commons as a row over anti-Semitism in politics rumbles on.
A suicide prevention charity called for an end to the sale of "Peachy Head" shampoo, telling ITV News it is "distasteful and dangerous."
Khan said sorry for using the racial slur 'Uncle Toms' during a television interview in 2009.