Don’t accidentally invite an unwanted guest to your summer picnic or barbecue. With warmer temperatures, the risk for foodborne illnesses such as listeriosis increase. Listeriosis can produce flu-like symptoms and for normal healthy people is usually not much of a concern. However, it can be very 
dangerous for the elderly, newborns, pregnant women, or people with a weakened immune system. For pregnant women, listeriosis can cause stillbirth or other problems, especially in the third trimester.
The bacteria listeria monocytogenes is frequently found in the environment and can grow in a wide range of temperatures including refrigerator temperatures and up to 150° F. Heat will kill it. Thus, for the elderly, pregnant women, and people with weakened immune systems, it is recommended they avoid foods at high risk of containing listeria:
- Soft cheeses such as brie, Camembert, blue-veined, feta, queso fresco, queso blanco, or queso panela made with unpasteurized milk
- Raw Sprouts
- Melons
- Hot Dogs
- Lunch and deli meat
- Smoked seafood
- Raw unpasteurized milk
Other foods that sometimes contain listeria include ice cream, deli salads, unpasteurized juice, raw or under-cooked eggs, and under-cooked meat, poultry or seafood.
Recommendations for everyone to avoid Listeria:
- Purchase items made only with pasteurized milk, including all kinds of cheeses.
- Always refrigerate cut melon right away and keep no longer than 7 days. Throw away cut melons that have been at room temperature for 4 hours or more. Always wash the whole melon before slicing.
- Use opened packages of hot dogs, lunch meat, pates, and cold cuts within a week, and use unopened packages within two weeks. Always store these items in the refrigerator, and don’t let juices from their packages contaminate other foods.
- Wash hands before and after handling foods, especially any raw or uncooked foods. For picnics, take hand wipes to clean hands if warm water and soap are not available. Wash hands before eating, too.
- Always wash raw vegetables and fruits thoroughly before eating.
- Make sure your refrigerator maintains a temperature between 34°F and 39° F.
- Wash and sanitize knives, cutting boards, countertops and your sink after handling uncooked foods.
- Keep uncooked meats separate from vegetables, cooked foods, and ready-to-eat foods.
- Cook meats to proper temperatures. Cook eggs until the white and yolk are firm.
Additional precautions at-risk populations should take to avoid Listeria:
- Avoid raw and lightly cooked sprouts of all kinds. If you want sprouts, be sure to cook them thoroughly to kill any bacteria.
Avoid eating hot dogs, lunch meats, cold cuts, other deli meats (such as bologna), or fermented or dry sausages unless they are heated to an internal temperature of 165° F just before serving.- Avoid refrigerated pâté or meat spreads from the deli, meat counter or the refrigerated section of a store.
- Avoid refrigerated smoked seafood unless it is canned or in a cooked dish, such as a casserole.
- Watch for product recalls and avoid any foods connected with recalls. Some frozen broccoli was recently voluntarily recalled due to possible listeria contamination.
Enjoy your summer with picnics and other outdoor activities – just remember to take precautions so that foodborne illnesses will not be a part of your summer. Let’s all have a food-safe summer!
