What is it?
- Listeria monocytogenes (Listeria) is a type of bacteria commonly found in soil, water, sewage and the gut of animals
- Listeria can grow in cold conditions, even in refrigerated food
What's the risk?
- Listeria can cause an illness called listeriosis
- Listeriosis is rare but for pregnant women, the elderly and people with weak immune systems the illness can be serious and fatal
- Listeria may cause pregnant women to miscarry or the baby can be born prematurely or stillborn
- Even a small amount of Listeria in food can cause illness
- Eating foods contaminated with Listeria is the most common way of contracting the illness. Listeria is tolerant to low temperatures so it can grow in food even if it is stored in the refrigerator
- Foods at higher risk of contamination include ready-to-eat foods (foods that won't be further cooked) such as pre-prepared salads and fruit; cold ready-to-eat chicken, deli meats and seafood; soft cheese, soft serve ice cream, unpasteurised milk and raw vegetables
Symptoms of listeriosis
- Symptoms usually start about 3 weeks after eating contaminated food, but can start from 3 to 70 days from infection
- Mild symptoms (generally in healthy people) may be mistaken for a mild viral infection or the flu: including fever, headache, tiredness and muscle aches. Less common symptoms are nausea, abdominal cramps and diarrhoea
- More severe illness can cause blood poisoning, inflammation of the brain and spinal cord, miscarriage or death
- Symptoms in pregnant women may appear mild, but it is important to seek medical attention immediately
Reduce your risk
- If you are pregnant, elderly or have a weak immune system, choose safer foods - see our advice for vulnerable people and our fact sheet Food safety for people at risk
- Avoid pre-prepared ready-to-eat foods, especially:
- cold meats from delicatessen counters and sandwich bars, and packaged, sliced ready-to-eat meats
- cold cooked ready-to-eat chicken (whole, portions, or diced)
- chilled seafood such as raw oysters, sashimi and sushi, smoked ready-to-eat seafood and cooked ready-to-eat prawns
- soft, semi-soft and surface-ripened cheeses such as brie, camembert, ricotta, blue and feta (unless thoroughly cooked)
- refrigerated paté or meat spreads
- pre-prepared or pre-packaged fruit or vegetable salads, including those from buffets and salad bars
- rockmelon
- raw seed sprouts
- soft serve ice cream
- unpasteurised fruit juices
- Don't eat foods that are past their use by date
- Cook food thoroughly and eat it immediately
- Refrigerated leftovers should be eaten within 3-4 days (or within 1 day for vulnerable people)
- Reheat food thoroughly until it is steaming hot (75°C)
- Make sure your fridge is running at 5°C or colder
- Wash raw fruit and vegetables thoroughly under running water
- Avoid cross contamination - use separate cutting boards and knives for raw and ready-to-eat food, and store cooked food separately from raw foods
- Wash your hands with soap and dry them before preparing and eating food
- Keep your kitchen and equipment clean
More information:
Food safety for people at risk fact sheet
Food safety for vulnerable people web page