Infection from Listeria monocytogenes typically occurs in individuals with a weakened or suppressed immune system. Here’s how it happens and what you can do to prevent Listeria from entering your home.
Could this happen to you or one of the women in your family?
Imagine you are pregnant. You are ecstatically happy and hopeful for the future. The new nursery is ready and the doctor tells you that all is well and on track for a healthy baby in a few more months. Then, imagine your pregnancy comes to a tragic and abrupt end. In your grief you begin to wonder – what went wrong? How can you lose your baby, your hope, and your happiness at your approaching parenthood to what? Foodborne illness? How can that happen? Listeriosis? What is that – I’ve never heard of it!
This is a true story. “I had had problems getting pregnant, but everything seemed to be going OK,” said a research participant in the research studies conducted at The Ohio State University and with collaborators at Colorado State University [reference, reference]. The bacteria, Listeria monocytogenes, causes an illness called listeriosis. If a woman is infected from eating contaminated food, the bacteria can travel through the bloodstream to the placenta and pass through to the fetus, even if the mother is not showing signs of illness. Once in the placenta, the fetus can become infected causing possible abortion, miscarriage, stillbirth or a baby born with health issues.
Pregnant women are at increased risk for getting some foodborne infections because of the hormonal changes that occur during pregnancy make them more susceptible to infections. Listeria monocytogenes, a major concern during pregnancy, is widely distributed in nature and can be found in the soil, on plants and decaying vegetation, and in animals and people. This is how food can become contaminated. Once inside the home, the bacteria has the ability to survive unfavorable conditions, like refrigeration temperatures, food preservatives (that is, salt), and food packaging that excludes oxygen.
The bacteria can, however, be easily destroyed by cooking. This is a good thing to remember! There are some very special tips to remember to help protect you from this serious foodborne illness [reference].
How you can Prevent Listeriosis
The most important way to reduce your risk of listeriosis is to keep your refrigerator below 40oF (4.4oC) and use perishable and ready-to-eat foods as soon as possible or within 4 days.
In addition, it’s best to AVOID these foods during pregnancy:
- Raw (unpasteurized) milk, raw milk cheese and yogurt products.
- Soft cheeses made from raw milk (Feta, Brie, Camembert, blue-veined cheeses, queso fresco, queso blanco and Panela). (NOTE: soft, raw milk cheeses may be eaten if heated to 160oF (71oC).)
- Refrigerated smoked or precooked seafood such as shrimp, crab and deli seafood salads.
- Hot dogs, deli meats and pâté, unless reheated to steaming hot before serving or reformulated to prevent Listeria.
- Raw or undercooked seafood (e.g., sushi, sashimi or ceviche).
More information about Listeria monocytogenes and other pathogens that can cause foodborne illness during pregnancy can be found in the booklet, Pregnancy and Foodborne Illness. Download a free copy.
For more about Listeria monocytogenes, read this factsheet – Listeria monocytogenes. A Concern for Pregnant Women and Older Adults
Are you a Health-Care provider or a Teacher who works with pregnant women? The Healthy Baby, Healthy Me educational curriculum was designed for you. The entire curriculum is available to you for FREE. Go to the Freebies page and click on Healthy Baby, Healthy Me (HBHM).