Listeria in Pregnancy

Pregnant women are constantly warned about the dangers of listeria.

Listeria is a type of food-borne bacteria that can be in a number of everyday foods. It can also be found in soil, animal faeces, vegetation and sewage. The possibility is very high of listeria entering and contaminating our food supply. This is why we all need to be very careful.

The levels commonly found in foods are generally harmless to the average person with a healthy immune system. However, during pregnancy if you eat listeria contaminated food and contract an infection you and your baby could be at risk.

Women who are pregnant are at a higher risk than the rest of the population of becoming infected. . This is because of changes to their metabolism and immunity, making them more susceptible.

The problem with listeria in pregnancy

Listeria can cause a rare but dangerous infection called listeriosis. If you contract listeriosis while pregnant the bacteria could reach your baby via the placenta. If this happens, there is a risk of a number of complications. These include blood poisoning, miscarriage, and premature labour or even stillbirth.

One difficulty with listeriosis is that it can easily be misdiagnosed. This is because the symptoms are easy to confuse with having influenza or another viral illness. Common, shared symptoms include; a fever or chills, muscle aches and back pain, diarrhoea and nausea.

The good news is that listeriosis in pregnant women is very rare in Australia and New Zealand. If you avoid soils and foods at risk of being contaminated it’s very unlikely that you will be infected. It is also important to follow safe hygiene habits when preparing and cooking foods.

Treatment for listeriosis

If you think you might have come into contact with listeria while you are pregnant and are feeling unwell, tell your healthcare professional. A blood or amniotic fluid test can confirm whether you have contracted listeriosis.

If your results are positive, a course of antibiotics will help to fight the infection. If diagnosed early enough, antibiotic treatment can also prevent the infection from being passed to your baby.

Avoiding listeria in pregnancy

Practising good food hygiene is the best way to avoid coming into contact with listeria.

Practise these simple steps whenever you are preparing or choosing food to eat:

• Always wash your hands
• Thoroughly wash fresh fruit and vegetables
• Cook all food, especially meat, seafood and dairy products, all the way through to kill the bacteria
• Serve and eat your meals while they are hot
• Reheat left overs or ready to eat foods until they are steaming hot
• Store any leftovers in the fridge immediately and eat within 12 hours of cooking
• Avoid all raw or partially cooked meats, seafood and soft cheeses
• Wash all cooking utensils and chopping boards with hot soapy water
• Avoid eating any food you’re not sure about

Certain foods are at higher risk of contamination with listeria. To be on the safe side, avoid these foods during pregnancy:

• Soft white and blue cheeses
• Soft-serve ice cream
• Any dairy products made from un-pasteurised milk
• Deli meats
• Pâté
• Pre-made and refrigerated salads, including fruit salads
• Seed sprouts
• Raw or smoked seafood including sashimi and oysters
• Cooked and chilled seafood including prawns
• Smoked salmon or trout
• Sushi