Reduce your risk of Listeria infection

Reduce your risk of Listeria infection

Person preparing vegetables on a wooden chopping board

Listeria infection (listeriosis) is caused by eating food that contains Listeria monocytogenes bacteria. Listeria infection is uncommon in healthy people but may cause severe illness in particular groups of the population.

Those at risk include:

  • pregnant women and their unborn or newborn babies
  • people with a weakened immune system due to chronic illness such as cancer, diabetes, alcoholism or who are using certain medications that impair immunity such as steroids and anti-cancer drugs

How do you get Listeria infection?

Listeria bacteria are widespread in the environment and can sometimes contaminate certain high-risk foods during or after the manufacturing process and the bacteria can continue to grow at refrigeration temperatures.

The infection is not normally transmitted between people; although it can pass from a pregnant woman to her unborn baby.

What are the symptoms of Listeria infection?

Symptoms usually occur around three weeks after eating contaminated food. This period can vary between a few days and two months.

Symptoms may include:

  • fever and chills
  • headache
  • stiff neck and sensitivity to light
  • confusion and drowsiness
  • muscle aches and pains
  • nausea
  • diarrhoea.

Healthy people and pregnant women may have mild or no symptoms, but Listeria infection may still result in miscarriage, premature birth or stillbirth.

In people at risk, Listeria infection can result in serious illnesses including meningitis (infection of the membrane surrounding the brain and spinal cord) and septicaemia (infection of the blood that can spread widely through the body).

What can I do to protect myself and my family?

The risk of infection by Listeria bacteria can be managed by following a few simple rules.

People at risk of Listeria infection should avoid high-risk foods which are known to be associated with Listeria bacteria contamination.

High-risk foods include:

  • pâté
  • cold ready-to-eat chicken
  • manufactured ready-to-eat meats such as polony, ham and salami
  • soft cheeses, including brie, camembert, blue cheese, fetta and ricotta
  • pre-packed, pre-prepared or self-serve fruit or vegetable salads and sandwiches
  • freshly squeezed fruit and vegetable juices
  • ready-to-eat cold, smoked or raw seafood including smoked salmon, oysters, sashimi and cooked prawns
  • sushi
  • soft serve ice cream and thick shakes
  • tofu and tempeh
  • unpasteurised milk and unpasteurised milk products.

You can reduce your exposure to Listeria bacteria by:

  • Washing fruit and vegetables, including herbs, before storage and use
  • Always washing your hands, knives and chopping boards with warm, soapy water before and after handling different kinds of food.
  • Ensuring that raw food is stored separately from cooked and ready-to-eat food, particularly in the fridge.
  • Cooking and reheating foods thoroughly as Listeria bacteria are killed by heating.

Seek medical advice

If you develop symptoms of Listeria infection and you are pregnant or have a weakened immune system, it’s important to see your doctor as soon as possible.

People with Listeria infection usually require hospitalisation and treatment with intravenous antibiotics.

To learn more, see our listeria infection fact sheet

For further information or to submit a story idea, please contact communications@health.wa.gov.au