The Centers for Disease Control and Prevention is warning us about picnic food, and what it says applies especially to seniors. It seems there's another potential food-borne illness: Listeria.

Picnic foods -- hot dogs, deli meats, prepared salads, meat spreads from the deli case and soft cheeses -- can contain bacteria called Listeria. Smoked seafood and unpasteurized milk also can harbor Listeria. Even if the bacteria has been killed by cooking, it can be recontaminated because the bacteria can grow at refrigerator temperature.

In addition to food poisoning, those with health risks can come down with a very serious infection after consuming Listeria-contaminated foods. Even for seniors without medical conditions, healing from an infection can include long hospitalizations -- or even death.

Here are some food safety tips from the www.IsItDoneYet.gov website:

• Use a digital thermometer to ensure that foods are cooked to the optimum temperature. For ground beef, that's 160 degrees Fahrenheit. Poultry needs to be heated to 165 F. Cooked hams must be reheated to 140 F. Check the temperature of the food in several places.
• Wash hands in warm, soapy water for at least 20 seconds before and after handling food.
• Keep refrigerator temperature at 40 degrees F or less, and freezers at 0 F or less.
• Keep your food-prep surface clean, and use paper towels instead of dish cloths to dry the counter.
• Rinse produce -- even the kind with rinds that aren't eaten.
• And those hot dogs and deli meats so popular with summer picnics: They must be completely heated to 165 degrees before consuming.

If you don't have Internet access, call the USDA Meat and Poultry Hotline 1-888-674-6854 to order the Food Safety for Older Adults pamphlet or if you have specific questions.