Foodborne illness

Throughout the year, we gather with friends and family for potlucks, parties, catered events, and celebrations in our homes and in restaurants. It is important to take steps to avoid food poisoning through the proper handling and preparation of food.

What causes a foodborne illness?

The most frequent causes are microorganisms such as bacteria or viruses. Most of us have seen or read news stories implicating the most common culprits, including salmonella, shigella, campylobacter, E coli 0157:H7, staphylococcus, clostridium perfringens, bacillus cereus and Norwalk-like viruses. Less commonly, the culprits are hepatitis A, clostridium botulinum (botulism), scombrotoxin, and vibrios.

Most of these microorganisms can’t be seen, smelled or tasted, but can cause illness that ranges from mild, to severe, to life-threatening.

Foodborne illness can be acquired in all settings where food is prepared and eaten, including homes, schools, and commercial food operations such as restaurants. It can also be acquired from contaminated drinking or swimming water.  Additionally, this illness can be passed from person to person if good hand washing practices are not followed.

Who is at risk for foodborne illness?

Those most at risk for contracting foodborne illness include older adults, babies and young children, and persons with weakened immune systems. There has been focus on the illness caused by Listeria, called listeriosis, because not only can it affect members of these high-risk groups but also unborn babies when acquired by pregnant women. To prevent this disease, expectant mothers should avoid soft cheeses, undercooked meat, pate, uncooked hot dogs, and deli meat.

What are the symptoms of a foodborne illness?

The most common symptoms can include fever, vomiting, diarrhea, abdominal bloating or cramping and muscle aches.  A common belief is that the illness is caused by the most recent foods or meal consumed. This can be a misconception because symptoms usually appear 12 to 72 hours after eating the contaminated food. Less often, symptoms can appear both sooner than 12 hours as well as up to a month later.

How can foodborne illness be avoided?

  • Do not prepare or handle food if you feel ill, are vomiting, or experiencing diarrhea.
  • Wash hands with soap and warm water:
    • Before and after preparing food 
    • When alternating between handling raw and cooked food to avoid cross contamination. This is especially important with raw meat, poultry, seafood, and eggs.
    • After using the bathroom or changing a diaper
    • After handling a pet
    • After coughing and sneezing
    • Before eating
  • Wash knives, cooking utensils and cutting boards in hot soapy water after preparation of each food item. This includes meat grinders and blenders. If cloths, rather than paper towels are used, wash them in a hot water cycle.
  • Rinse raw produce in water even if the outside skin or rind is not going to be eaten. For some produce using a small brush to remove surface dirt might be necessary. 
  • Refrigerate all perishable food as soon as possible after purchasing. If the ride home is more than 60 minutes in warm/hot weather, place cold items in an insulated cold storage container. 
  • Purchase an easy-to-use food thermometer that has a wide range of temperatures from 40 degrees Fahrenheit (F) or less to 165 degrees F or more.
  • Cool all leftovers to 40 degrees F or lower within 4 hours after cooking. The use of smaller, shallow containers helps with this rapid cool down.
  • Do not leave foods containing meat, milk, eggs, fish, or poultry at room temperature for more than the four-hour limit. This includes pumpkin or other custard pies.
  • Heat leftovers to 165 degrees F, and if liquid, boil first before serving.
  • Place uncooked meats and poultry in a sealed plastic bag before storing in the refrigerator to avoid juices spilling onto other foods. 
  • Use a cooking thermometer. Turkey and stuffing should be thoroughly cooked to at last 165 degrees F.  The safest practice is to cook stuffing separately in a casserole dish.
  • If uncooked eggs are part of a recipe, use pasteurized egg products instead of shelled eggs.
  • Keep cooked meats hot (140 degrees F), and ideally serve them within 30 minutes of cooking.
  • Do not thaw food at room temperature. Plan far enough ahead so that there is sufficient time.

The following table should be used as a reference for determining thawing times based on weight of poultry and meat.

4-12 pounds 1 to 3 days
12-16 pounds 3 to 4 days
16-20 pounds 4 to 5 days
20-24 pounds 5 to 6 days

The U.S. Department of Agriculture operates a Meat and Poultry Hotline (1-800-535-4555) for other specific questions.

What should I do if I think I have foodborne illness?

Call your doctor if you are severely ill, cannot keep fluids down, are having diarrhea or are experiencing symptoms of dehydration.  Dehydration symptoms can include decrease in urination, dry mouth or dizziness when first standing. Also call if you have a high fever (over 101.5), blood in your stool, or if your illness lasts longer than one to two days. Young children and babies can become severely ill and dehydrated quickly so contact your child’s doctor immediately if you suspect foodborne illness.

If you believe that you acquired this illness from a commercial food source such as a restaurant, notify your local public health department.

Additional resources
Index for food-related diseases—Centers for Disease Control and Prevention
Fight Bac!—Partnership for Food Safety Education 
Prevention foodborne illness—APIC consumer alert