In this article:
What is Listeria and Why is it Riskier in Pregnancy?
Listeria is a type of bacteria found in soil, water, and animal waste. It can contaminate food, leading to listeriosis when you eat that food. During pregnancy, your body becomes more vulnerable to infections like Listeria compared to other healthy adults. It is 18 times more common in pregnancy than in non-pregnant individuals.Even a mild infection can have serious consequences for your baby. It can pass from you to your baby through the placenta even if you have no symptoms at all. That is why staying cautious with your food choices is very important during this time.
How Does Listeria Spread?
Listeria bacteria can contaminate a variety of foods, especially those that aren’t properly cooked or pasteurised. Unlike many other bacteria, Listeria can survive and grow in cold temperatures, such as in your fridge. You may get infected by eating contaminated foods or, in rare cases, through contact with contaminated surfaces.Common sources of Listeria include:
- Raw or unpasteurised milk and dairy products like soft cheeses.
- Ready-to-eat meat, like deli meats or hot dogs.
- Cold-smoked fish.
- Raw or lightly cooked sprouts.
- Unwashed fruits and vegetables, especially melons.
- Prepared deli salads like egg or tuna salad.
- Pregnant parents can pass the infection to their baby during pregnancy or at birth.
Symptoms of Listeria in Pregnancy
Listeria symptoms in pregnant individuals are often mild and can feel like a cold or flu. Some may not even notice they’re infected, which makes it tricky to detect. Symptoms usually start within a few days to two months after eating contaminated food.Symptoms you might notice:
- Fever or chills.
- Muscle aches or tiredness.
- Sore throat.
- Upset stomach, nausea, or vomiting.
- Diarrhoea or loose stools.
- Severe headache or stiff neck.
- Confusion or changes in alertness.
- Loss of balance or coordination.
- Sensitivity to light.
Symptoms in Newborns
If your baby is infected with Listeria, the symptoms may not be obvious but can be serious. These signs can appear at birth or up to two months later.Signs of listeria in newborns:
- Lack of interest in feeding.
- Being unusually fussy or cranky.
- Fever or low body temperature.
- Vomiting or trouble breathing.
- Lack of energy or low birth weight.
Risks and Complications for You and Your Baby
Listeriosis is rare, but its complications during pregnancy can be severe. Any delays in treatment may lead to serious outcomes.Risks For You
- Sepsis is a dangerous reaction in your bloodstream that can cause organ damage.
- Meningitis can lead to nerve problems, hearing loss, or seizures.
Risks For Your Baby
- Miscarriage or stillbirth.
- Premature birth.
- Severe infections like sepsis or meningitis occur after birth.
- Long-term issues include neurodevelopmental issues (intellectual disabilities), paralysis, blindness, or organ damage to the brain, kidneys, or heart. These outcomes are less common with timely treatment.
How is Listeria Diagnosed?
If your healthcare professional suspects listeriosis, they’ll run tests to confirm it. This is especially important if you have symptoms and have eaten foods that might be contaminated.- A blood culture is used to grow bacteria from a sample of your blood.
- After birth, the placenta may also be tested for Listeria.
Treatment for Listeria in Pregnancy
Listeriosis is treatable with antibiotics, which can help protect you and your baby. Getting treated early is crucial to reduce the risk of complications. If you are diagnosed, your doctor will prescribe oral antibiotics to control the infection and prevent it from spreading to your baby. If your newborn shows signs of listeria, they will also receive antibiotics to treat the infection and prevent serious issues.How to Prevent Listeria During Pregnancy
Preventing listeriosis is all about being careful with what you eat and how you handle food. By following simple food safety guidelines, you can greatly reduce your risk. Try to avoid these foods during pregnancy:- Raw milk, homemade paneer, or khoa made from unpasteurised milk.
- Local soft cheeses, or imported cheeses like feta, brie, camembert, or blue cheese (even if pasteurised, to be safe).
- Undercooked or raw meat and poultry. Pre-cooked or refrigerated meats can be contaminated with Listeria. Reheat them until steaming hot before eating to kill the bacteria.
- Cold-smoked fish.
- Raw or lightly cooked sprouts.
- Unpasteurised fruit juices.
- Street foods prepared in unhygienic conditions.
- Cut melons left at room temperature for over four hours or not used within seven days of refrigeration.
Safe Food Handling Tips
- Wash your hands with soap and water for at least 20 seconds before and after preparing food.
- Scrub raw fruits and vegetables under running water with a brush before eating or cooking.
- Avoid rinsing raw meat or poultry to prevent spreading bacteria.
- Cook meat, poultry, and eggs thoroughly.
- Use deli meats within 3 to 5 days of opening or within two weeks if unopened.
- Throw out food past its expiration date, or if it smells or looks off.
If you’re trying to conceive, start following these guidelines early to reduce your risk.
When to Contact Your Healthcare Professional
Don’t wait to seek medical help if you think you might have been exposed to listeria or notice any symptoms. Don’t panic as the risk of infection is still low, but it’s wise to take early action to protect you and your baby.Call your healthcare professional if:
- You have a fever, muscle aches, an upset stomach, or diarrhoea.
- You have eaten food that was taken off the market because it may be contaminated with Listeria. This includes items like unpasteurised dairy or undercooked deli meats.
- A high fever or severe headache.
- Stiff neck or confusion.
- Sensitivity to light or loss of balance.
Listeria infection is rare and treatable, so you don’t need to live in fear. You can keep your risk very low by avoiding high-risk foods like soft cheeses, deli meats, unpasteurised dairy, and following good food safety habits. Reach out to your healthcare professional right away if you think you’ve eaten something risky. It's possible to enjoy a healthy and safe pregnancy with the right care and awareness.
FAQs on Listeria Infection in Pregnancy
- How do I know if I have listeria while pregnant?
Symptoms can feel like the flu and may include fever, chills, muscle aches, nausea, or diarrhoea. Some people may not feel sick at all. If you suspect you’ve eaten risky food and feel unwell, call your doctor. - What foods should I avoid to prevent listeria?
Avoid unpasteurised milk, soft cheeses, undercooked meats, deli meats, raw sprouts, and cut melons left out too long. - How long after eating contaminated food do Listeria symptoms appear?
Symptoms can appear anywhere from a few days to 2 months after exposure, which makes it harder to link to a specific food.
