Protecting you and your unborn baby from Listeria monocytogenes just takes following these careful food selection and preparation tips
Tips for Moms-to-Be
What Is It? Listeria monocytogenes is a bacterium that can be found in ready-to-eat, perishable foods such as dairy, meat, poultry, and seafood. It's unusual because it can grow at refrigerator temperatures where most other foodborne bacteria do not. It can also be particularly harmful to you and your unborn baby. For more information, see Listeria.
Check Time and Temperatures
- Your refrigerator should register at 40° F (4° C) or below and the freezer at 0° F (-18° C). Place a refrigerator thermometer in the refrigerator, and check the temperature periodically. During the automatic defrost cycle, the temperature may register slightly higher than 40° F. This is okay.
- Refrigerate or freeze perishables, prepared food, and leftovers within two hours of eating or preparation. Follow the 2-Hour Rule: Discard food that's left out at room temperature for longer than two hours. When temperatures are above 90° F (32° C), discard food after one hour.
- Use ready-to-eat, perishable foods, such as dairy, meat, poultry, seafood, and produce, as soon as possible.
Clean the Fridge
- Clean your refrigerator regularly.
- Wipe up spills immediately.
- Clean the inside walls and shelves with hot water and a mild liquid dishwashing detergent; then rinse.
- Once a week, check expiration and "use by" dates, and throw out foods if the date has passed. Follow the recommended storage times for foods. See the Refrigerator & Freezer Storage Chart (PDF).
To Eat or Not to Eat?
- Hot dogs, deli meats, and luncheon meats - unless they're reheated until steaming hot.
- Soft cheeses like Feta, Brie, and Camembert, "blue-veined cheeses," or "queso blanco," "queso fresco," or Panela - unless they're made with pasteurized milk. Make sure the label says, "made with pasteurized milk."
- Refrigerated pâtés or meat spreads.
- Refrigerated smoked seafood - unless it's in a cooked dish, such as a casserole. (Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna, or mackerel, is most often labeled as "nova-style," "lox," "kippered," "smoked," or "jerky." These types of fish are found in the refrigerator section or sold at deli counters of grocery stores and delicatessens.)
- Raw (unpasteurized) milk or foods that contain unpasteurized milk.
It's okay to eat:
- Canned or shelf-stable (able to be stored unrefrigerated on the shelf) pbtés and meat spreads.
- Canned or shelf-stable smoked seafood.
- Pasteurized milk or foods that contain pasteurized milk.
"I've heard about Listeria monocytogenes in relation to pregnancy. What is it that makes this bacterium more harmful to me and my baby than other foodborne bacteria?"
All foodborne bacteria can pose a risk to pregnant women and people in general, so it's important for everyone to always follow good food safety practices. But, because a pregnant woman's immune system is constantly changing during these nine months, certain foodborne pathogens, such as Listeria monocytogenes and Toxoplasma gondii (a parasite that can be found in raw or undercooked pork, lamb, or venison; contaminated water; and cat litter) and methylmercury (a metal found in some fish and shellfish), are more effective in crossing the placenta into the fetus than other foodborne pathogens.
These risks often don't make the mother feel very sick, but can have a severe effect on her unborn baby. The good news is... they're easy to prevent! (See Lifelong Food Safety for four easy steps for preventing foodborne illness.) For more information, see Listeria and Toxoplasma.
"Does the temperature of my refrigerator really matter in helping reduce the growth of Listeria monocytogenes?"
Yes, making sure that the inside temperature of your refrigerator registers at 40: F (4: C) is really important! Listeria monocytogenes can grow at refrigerator temperatures, but at 40: F (4: C) or below, it grows more slowly. Remember, the more bacteria there are, the greater the chances for foodborne illness. Plus, using ready-to-eat, perishable foods as soon as possible means that Listeria monocytogenes has less time to grow. And, be sure to follow the guidelines above for cleaning your refrigerator. This will also help keep Listeria monocytogenes at bay!
"I've read about food recalls in the news involving Listeria monocytogenes. What should I do if I have food that's recalled because of Listeria monocytogenes?"
Don't eat any food that's recalled and removed from grocery store shelves. Always return recalled food to the place where you bought it. For the latest product recalls, see this Web site: www.recalls.gov.