General Practice

Listeria | What is it?

Listeria is a foodborne bacteria which can make you sick. Infection with listeria bacteria is called listeriosis.

Listeria is a common bacterium (bug) widely found in dust, soil, water, plants, sewage and animal droppings. It can be transmitted through infected food.

It usually causes few or no symptoms, but can be serious for pregnant women, newborn babies, older people, and people with weakened immune systems. On average, symptoms appear after about 3 weeks but may appear as late as 2 months after you have eaten something with listeria.

Listeria and pregnancy

If a pregnant woman develops an infection caused by listeria (listeriosis), it can cause miscarriage and stillbirth. Newborn babies who develop listeriosis can have difficulty breathing, develop a chest infection, and inflammation of the coverings of the brain (meningitis).

Pregnant women and others at risk should not eat foods most likely to contain listeria, including unpasteurised milk and cheese, some seafood and processed meats such as luncheon meat and salami, cold precooked chicken, pre- packaged or stored salads ,soft-service creams, and some dips and spreads.


If you think you have eaten food contaminated with listeria or if you have any of the symptoms of listeria infection, contact your doctor or midwife right away. Remember that it can take 2 months for symptoms to appear.

For more information, visit Health Navigator here.

If you are concerned about listeria, call Healthline on 0800 611 116 or contact your doctor or practice nurse.