Listeria monocytogenes
A bacterium that survives refrigeration and is a frequent cause of Class I recalls in deli meats, soft cheese, and ready-to-eat foods.
Listeria monocytogenes is a bacterium that causes listeriosis, a serious infection. It is dangerous because it grows at refrigerator temperatures, so chilling food does not stop it the way it slows most other bacteria.
Listeria is especially risky for pregnant people, newborns, adults over 65, and anyone with a weakened immune system. In pregnancy it can cause miscarriage and stillbirth even when the parent has only mild symptoms. For most healthy adults it causes fever and digestive symptoms, but the high-risk groups face hospitalization and death.
Because of this, Listeria contamination almost always triggers a Class I recall. Common sources are deli meats, hot dogs, soft cheeses, smoked fish, sprouts, and pre-cut produce. Ready-to-eat foods are the biggest concern because there is no cooking step to kill the bacteria before eating.
If a product you have is part of a Listeria recall, do not eat it and do not rely on smell or taste, because contaminated food looks and tastes normal. Clean the fridge area where it was stored, since Listeria can spread to other surfaces and foods.
Related terms
Class I Recall
The most serious FDA recall class, used when a product has a reasonable chance of causing serious health harm or death.
Recall Classification (I, II, III)
The FDA's three-level system that ranks how dangerous a recalled product is, from life-threatening (I) to a labeling-only issue (III).
Salmonella
A bacterium behind many food recalls and outbreaks, found in poultry, eggs, produce, and increasingly in dry foods like powdered milk and flour.