What You Need to Know About Preventing Listeria Infections
Pregnant people are about 10 times more likely than the general population to become infected with a germ called Listeria, resulting in a disease called listeriosis. Because immune systems are altered during pregnancy, it is harder for pregnant people to fight off such infections.
The risk of listeriosis increases to about 24 times greater than that of the general population if the pregnant person is Hispanic. This higher incidence may be related to the increased consumption of foods highly susceptible to Listeria contamination, like queso fresco-type cheeses.
Infections with Listeria can be fatal, especially among unborn or newborn babies, adults over the age of 65, and people with weakened immune systems or chronic diseases. Listeriosis in pregnant people can lead to serious complications with their pregnancy, including miscarriage and stillbirth.
The Risk
Certain foods – including ready-to-eat refrigerated foods, unpasteurized (raw) milk, and foods made with unpasteurized milk – often may be contaminated with a bacteria called Listeria, the third leading cause of death from food poisoning in the United States. These foodborne bacteria can grow at refrigerator temperatures and can cause an illness that in most healthy people is unpleasant but not serious. But in people who are at high risk, Listeria can cause an illness called listeriosis which can be severe and even lead to death. Those at high risk include pregnant people and their unborn babies, newborns, older adults, and other persons with weakened immune systems, such as those with HIV/AIDS, cancer, diabetes or kidney disease, and transplant patients.
While a pregnant person may have only a mild, flu-like illness, or may not feel sick at all, listeriosis can lead to miscarriage, death of the unborn baby, a low-birth-weight infant, health problems for the newborn, or even infant death. That’s why reducing risks from Listeria is so important.
How to Reduce Your Risk from Listeria: 3 Easy Steps
There are three very simple things you can do to help prevent illness from Listeria:
1. Chill at the Right Temperature
The right temperatures slow the growth of Listeria. If your refrigerator does not have electronic digital controls, put a thermometer in the refrigerator and adjust the refrigerator temperature control, if necessary. Put a second thermometer in the freezer.
Your refrigerator should register at 40° F (4° C) or below and your freezer at 0° F (-18° C).
2. Use Ready-to-Eat Foods Quickly!
The longer a food is stored in the refrigerator, the greater the chance for Listeria to grow. Also, if foods develop an off odor, flavor or texture due to naturally occurring spoilage bacteria, they should not be eaten.
3. Keep the Refrigerator Clean
Clean your refrigerator regularly.
Wipe up spills immediately. This is particularly important, so Listeria doesn’t have a place to grow and then spread to other foods.
Clean the inside walls and shelves with hot water and a mild liquid dishwashing detergent, rinse, then dry with a clean cloth or paper towel.
Cold Storage Temperature Check!
Chilling stored foods to proper temperatures is one of the best ways to slow the growth of dangerous bacteria, like Listeria.
A refrigerator thermometer can make a big difference!
- Put the thermometer in the middle of the refrigerator. After 5 to 8 hours, if the temperature is above 40° F (4° C), adjust the refrigerator temperature control to a lower setting. Check again after 5 to 8 hours.
- Put the thermometer between frozen food packages in the freezer. After 5 to 8 hours, if the temperature is above 0° F (-18° C), adjust the freezer temperature control to a lower setting. Check again after 5 to 8 hours.
To Eat or Not to Eat?
Choosing the right foods and preparing them safely helps reduce the risk illness from Listeria for at-risk people.
| High Risk Foods | Lower Risk Foods |
|---|---|
| Hot dogs and luncheon meats – unless they’re thoroughly reheated | Hot dogs and luncheon meats that are heated to an internal temperature of 165° F (74° C) measured with a food thermometer |
| Any type of cheese made with unpasteurized (raw) milk | Cheeses made with pasteurized milk, other than queso fresco-type cheeses |
| Any queso fresco-type cheeses, (made with either unpasteurized or pasteurized milk) such as queso fresco, queso blanco, or requesón | Cheeses made with pasteurized milk, other than queso fresco-type cheeses |
| Refrigerated pâtés or meat spreads | Canned or shelf-stable* 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 grocery store refrigerator sections or deli counters or sold at delicatessens.) | Canned or shelf-stable* smoked seafood. |
| Unpasteurized milk or foods that contain unpasteurized milk | Pasteurized milk and foods made with pasteurized milk – except pasteurized queso fresco-type cheeses |
*Foods that can be safely stored at room temperature, or “on the shelf,” are called shelf stable.
Take Action
If you think that you or a family member has a foodborne illness, contact your healthcare provider immediately. Also, report the suspected foodborne illness to FDA in either of these ways:
- Visit https://www.fda.gov/fcic for additional consumer and industry assistance.
- Contact the Consumer Complaint Coordinator in your area.
- Contact MedWatch, FDA’s Safety Information and Adverse Event Reporting Program:
- By Phone: 1-800-FDA-1088
- Online: File a voluntary report at http://www.fda.gov/medwatch