Listts are rod-shaped bacteria that can move independently with their flagella. They are extremely resistant and survive both freezing and drying without damage.
They can be killed by heating. They do not develop further in particularly salty or acidic environments.
Listeria can also develop further in refrigeration and in the absence of oxygen, e.g. in packaging, and are therefore a particular problem for the food industry.
Listeria reside in human and animal organisms. Foods of animal origin, such as raw meat and raw milk, are therefore particularly at risk. These products can become contaminated during slaughter, cutting or milking. Raw products in particular are therefore easily affected.