Food Safety

Preventing Food Poisoning

Handling food the right way can help you avoid germs that can make you sick. Keep food safe and avoid illness by following these basic food safety rules:

Washing hands with soapClean

Frequently wash hands and surfaces touched by food. Germs can spread throughout the kitchen and get onto cutting boards, knives, counter tops, sponges, and towels. For more information, visit Food

Rainbow Trout stuffed with herbs on cutting boardSeparate

Don't let germs spread from one food product to another. This is especially true for raw meat, poultry, and seafood. Keep these foods and their juices away from other foods. For more information, visit Food


Checking fish for doneness with meat thermometerCook

Foods are properly cooked when they are heated for a long enough time and at a high enough temperature to kill harmful germs that cause illness. For more information, visit Food

Always use a thermometer to make sure meat, poultry, or fish reach a safe minimum cooking temperature.

Open refrigerator full of foodChill

Refrigerate promptly to keep harmful germs from growing and multiplying. Refrigerators should be set at 40° Fahrenheit and the freezer at 0° Fahrenheit. Check the accuracy of the settings with a thermometer. For more information visit, Food

Important Causes of Foodborne Illness

Foodborne illness, often called food poisoning or foodborne disease, is any illness caused by eating contaminated food. It is a common cause of diarrhea in Wisconsin.

Botulism - Foodborne

Foodborne botulism is a rare but serious illness caused by a toxin that attacks the body’s nerves. The toxin is made by the Clostridium botulinum bacteria. This toxin may not give a bad odor or taste to food. Most of the time, botulism occurs when improperly preserved foods are not cooked well enough. However, commercial foods and restaurants are still sources of some botulism cases. Symptoms of botulism are double vision, blurred vision, drooping eyelids, slurred speech, difficulty swallowing, a thick-feeling tongue, dry mouth, and muscle weakness. If you or someone you know has symptoms of botulism, see your doctor or go to the emergency room immediately.


Campylobacteriosis is an infection caused by Campylobacter bacteria. It is one of the most common causes of diarrhea in the U.S. It affects the intestinal tract and, rarely, the bloodstream. Most cases of campylobacteriosis are caused by eating undercooked poultry or meat, or from cross-contamination of other foods by these items. Outbreaks of Campylobacter in Wisconsin have most often been associated with eating unpasteurized dairy products.

Clostridium perfringens

Clostridium perfringens is one of the most common types of foodborne illness in the U.S. The bacteria can be found on raw meat and poultry, as well as in the intestines of animals and humans. Food most often linked to C. perfringens illness are large quantities of food, especially meat or meat-containing dishes, that were not heated or cooled to proper temperatures. Common symptoms are diarrhea and stomach cramps within 6 to 24 hours (typically 8 to 12 hours) of eating contaminated food. The illness usually begins suddenly and lasts for less than 24 hours. Symptoms usually do not include fever or vomiting. The illness is not passed from one person to another. For more information, visit Food


Cyclosporiasis is an illness caused by the parasite Cyclospora cayetanensis. The Cyclospora parasite is spread when people eat food or drink water that has been tainted with feces (poop). Cyclospora is not typically found in the U.S. People in the U.S. most commonly become infected when traveling to tropical or subtropical regions where it is found, or by eating contaminated fresh produce imported from those areas. The symptoms of cyclosporiasis are frequent, watery diarrhea along with loss of appetite, stomach cramps, bloating, increased gas, nausea, and tiredness. Symptoms may last for several weeks.

E. coli

Escherichia coli (E. coli) are a group of bacteria found in the intestines of people, and animals, which can also be found in the environment. Most types of E. coli are harmless and serve an important role in our digestive system. However, some types of E. coli can cause illness in humans. Many of these types of E. coli cause diarrhea and are referred to as diarrheagenic E. coli. One group of E. coli called Shiga toxin-producing E. coli (or STEC) are an important cause of foodborne infections.

Hepatitis A

Hepatitis A is a liver disease caused by the hepatitis A virus. The virus enters through the mouth, multiplies in the body, and is passed in the poop. If careful handwashing with soap is not done after using the bathroom, the virus can then be carried on an infected person's hands. From there, the virus can be spread to others by direct contact or by eating or drinking food that was touched by the ill person. Sometimes, it can be spread by drinking unclean water that has been tainted with poop. Because the virus is spread through poop, children with hepatitis A who are not toilet trained can easily spread the virus. Hepatitis A can be prevented by vaccination against the disease.


Listeriosis is an illness caused by eating food with the bacteria Listeria monocytogenes. People at risk for becoming ill with listeriosis include pregnant women and their unborn babies, newborns, the elderly, and those with weakened immune systems. The symptoms of listeriosis may include sudden onset of fever, muscle aches, chills, and sometimes nausea or diarrhea. Infected pregnant women may experience only a mild gastrointestinal illness, but L. monocytogenes can be spread to the fetus even if the mother does not have symptoms. This can lead to infections in the newborn, premature delivery, miscarriage, or stillbirth. See the list of foods to avoid during pregnancy.


Norovirus is the leading cause of person-to-person and foodborne outbreaks in Wisconsin. The virus enters through the mouth, multiplies in the body, and is passed in the feces (poop) and in vomit. If careful handwashing with soap is not done after using the bathroom, the virus can then be carried on an infected person's hands. From there, the virus can be spread to others by direct contact or by eating or drinking food that was touched by the ill person. Symptoms of norovirus are vomiting, diarrhea, and abdominal cramping. Norovirus is often incorrectly referred to as “the stomach flu”; however, norovirus illness is not related to the flu (influenza), which causes respiratory symptoms. Because there are many types of norovirus, you can get it multiple times in your lifetime.


Salmonellosis is an illness that is caused by Salmonella bacteria. It generally affects the intestinal tract and occasionally urine, the bloodstream, or other body tissues. It is a common cause of diarrhea in Wisconsin. Salmonella bacteria are spread by eating or drinking contaminated food or water, or by direct or indirect contact with poop from infected people or animals. The bacteria can be found in raw meats, poultry, eggs, and raw dairy products as well as fresh fruits and vegetables, and even some processed foods. People may also become exposed to Salmonella bacteria through contact with animals such as live chicks, cattle, reptiles, or sometimes dogs and cats. Symptoms can include mild to severe diarrhea, abdominal pains, fever, and occasionally vomiting for several days.


Vibriosis is an illness caused by about a dozen Vibrio species. Vibrio species can cause gastrointestinal illness, infection of the bloodstream, and wound infections. The most common species causing human illness in the U.S. are Vibrio parahaemolyticus, Vibrio vulnificus, and Vibrio alginolyticus. Most people become infected with vibriosis by eating raw or undercooked shellfish, particularly raw oysters. Certain Vibrio species can also cause a skin infection when an open wound is exposed to brackish or salt water. People with compromised immune systems, especially those with chronic liver disease, are more likely to get vibriosis. Eating raw seafood, especially oysters, and exposing open wounds to brackish or saltwater can increase a person’s chance for getting vibriosis.


Yersiniosis is an illness caused by the bacterium Yersinia enterocolitica. Anyone can get yersiniosis from eating contaminated food, especially raw or undercooked pork products. Drinking unpasteurized milk or untreated water can also cause illness. Symptoms of yersiniosis depend on the age of the ill person. In young children common symptoms are fever, abdominal pain, and diarrhea, often bloody. In older children and adults, lower right-sided abdominal pain and fever may be confused with appendicitis.

Refrigerator Safety

The way you store your food can make the difference between healthy, great tasting meals or food poisoning.

The US Department of Agriculture (USDA) offers these tips:

French door refrigerator full of fruits and vegetables

  • Always refrigerate perishable food within two hours (one hour when the temperature is above 90 °F).
  • Check the temperature of your refrigerator and freezer with an appliance thermometer. The refrigerator should be at 40 °F or below and the freezer at 0 °F or below.
  • Cook or freeze fresh poultry, fish, ground meats, and variety meats within two days; other beef, veal, lamb, or pork, within three to five days.
  • Perishable food such as meat and poultry should be wrapped securely to maintain quality and to prevent meat juices from getting onto other food.
  • To maintain quality when freezing meat and poultry in its original package, wrap the package again with foil or plastic wrap that is recommended for the freezer.

Safely Eating Out

Going out to eat allows you to try new foods and spend time with friends and family. When you eat out it is important to keep a few things in mind:

  • If you become sick, and you think a meal from a restaurant caused your illness, remember to report your illness to your local health department.
  • The food you eat may smell, taste, and look fine, but more than half of foodborne outbreaks are linked to restaurants. High risk foods include meat, seafood, poultry, and eggs. If not fully cooked, these foods may have germs that can make you sick. These items must be fully cooked in order to reduce your risk of getting sick. Don’t be afraid to send your food back if it is not fully cooked.
  • Make sure you put your leftovers in the fridge within two hours of eating, or one hour if the outside temperature is above 90 degrees. Make sure to reheat your leftovers to 165 degrees.

Kitchen section in a restaurant

Special Holiday Treats

Some traditional holiday treats may have some special guidelines for safe seasonal enjoyment:

Raw meat with garnish in white dish

Tiger Meat or Cannibal Sandwiches: For some Wisconsinites, it’s a tradition to eat raw ground beef dishes, often referred to as tiger meat, steak tartare or cannibal sandwiches.

It is important to know that eating these types of foods is not without risks. Salmonella, E. coli O157:H7, Campylobacter and Listeria are bacteria that can be found in raw and undercooked beef. Regardless of where you buy your ground beef, these risks are real.

Since 1986, eight outbreaks have been reported in Wisconsin linked to eating a raw ground beef dish, including a large Salmonella outbreak involving more than 150 people during December 1994. Ground beef should ALWAYS be cooked to an internal temperature of 160° F.

Holiday Eggnog with Whipcream

Baked goods: The U.S. Food and Drug Administration advises consumers not to eat uncooked cookie dough, whether homemade or commercial, or batters made with raw fresh eggs. This is because raw fresh eggs may contain the bacteria Salmonella, and flour used in baking has been linked to E. coli outbreaks. Proper and complete cooking kills bacteria that cause these infections.

Eggnog: Traditional eggnog made with raw eggs is also a potential risk, again because the raw egg may contain the bacteria Salmonella. While cooking can destroy the disease-causing bacteria, consumers can still become ill when the eggnog is left at room temperature for several hours before being consumed. Safe alternatives are pasteurized eggnog beverages sold in grocery dairy cases; these products should be kept refrigerated.

Apple cider and other juices: Apple cider is often served during the holiday season. Apple cider and most juices available at grocery stores are pasteurized or otherwise treated to destroy harmful bacteria. However, unpasteurized or raw juice may be found in the refrigerated sections of grocery stores, or at health-food stores, cider mills or farm markets. Such juices must have this warning on the label:

WARNING: This product has not been pasteurized and therefore, may contain harmful bacteria that can cause serious illness in children, the elderly, and persons with weakened immune systems.

If you can't tell whether a juice has been processed to destroy harmful bacteria, either don't use the product or boil it to kill any harmful bacteria.



Mail-order food

Use caution when eating mail-order food, such as meat, poultry, fish and other perishables such as cheese, fruit, and cheesecake.

The person receiving the food should make sure they know when it is going to be delivered.

When it arrives, the package should be opened immediately. If the package is labeled "keep refrigerated" it should be chilled when it arrives.

More Food Safety Resources

Last Revised: January 4, 2021