Foodborne Illness

Common bacteria and viruses that cause food poisoning. An informational site sponsored by Marler Clark

Frequently Asked Questions

Q. Is eating restaurant food riskier than cooking at home?

Because you have more control over the food you prepare at home, if you practice safe food handling while preparing meals, you are probably less likely to contract a foodborne illness at home. For information on safe food preparation, see the USDA’s guidelines on safe food handling.

Q. What is the most effective way to wash my hands in order to get rid of germs?

The USDA recommends that you wash your hands thoroughly with soap in warm water for at least 20 seconds. Make sure to scrub under your fingernails, between your fingers, and on the backs of your hands.

Q. Could my food poisoning symptoms come from a restaurant I ate at a week ago?

Yes, this is possible. If you have food poisoning symptoms, they are not necessarily from the meal you just ate. In fact, symptoms for the most common pathogens do not appear for up to 12 hours after eating the contaminated food, and can appear up to a week later.

Q. If I have food poisoning, how do I report my case?

The majority of foodborne illness cases go unreported. If you think you have contracted a foodborne illness, you should see a doctor so that he or she can confirm your diagnosis. At this point, the doctor will report his or her findings to the health department. If you did not see a doctor for your illness, but have reason to believe that you have food poisoning, you can also call your local health department to report it.

Q. How do I find out whether a restaurant has a history of serving contaminated food?

Environmental health practitioners from local health departments routinely conduct restaurant inspections. The results of these inspections can be found on your local health department’s website, or by contacting the department directly.

Q. Am I taking a risk by eating vegetables such as tomatoes and spinach raw?

There is always a slight risk of contamination when eating raw foods. However, you can reduce the risk of illness from these foods by washing them thoroughly before you eat them.

Q. Is it safe to cook raw meat and vegetables together in the same pan at the same time?

Yes, this is a safe method of cooking, as long as everything in the pan is fully cooked before eating.

Q. If I have food poisoning, how long should it last?

Depending on the type of foodborne illness you have, and your personal biology, symptoms can last anywhere from a few hours to a few weeks. You can look up duration of illnesses for specific pathogens by clicking on the “Subject” links on the right.

Q. What is pasteurization? Once something has been pasteurized, can I eat it uncooked?

Pasteurization is a heat treatment applied to dairy products and juice in order to kill potentially dangerous pathogens. A product’s label will tell you whether or not the product has been pasteurized. Pasteurization greatly reduces the risk of contamination, however, there is always a chance that a product will be contaminated after the pasteurization process.

Q. I like my steak medium rare. Am I putting myself in danger by eating undercooked beef?

Beef that is not well-done can still be safe. It is important to make sure that the internal temperature of the mean reaches 145°F for whole pieces of meat. For ground beef products, the internal temperature must reach 165°F. Pork and poultry, on the other hand, must be cooked all the way through.

Q. What is the difference between a bacterial foodborne illness and a viral one?

While bacterial and viral infections often share the same symptoms, they are two very different types of pathogens. A bacterium is a single-celled organism that which causes illness when ingested. Unlike viruses, bacteria can grow on the food they contaminate. Most foodborne illnesses come from bacteria. A virus is non-living, and is usually spread from person to person. While some antibiotics may be used to treat bacterial infections, they are ineffective with viral ones.

Q. If my child or I have diarrhea, should I see a doctor?

You should see a health care provider if your diarrhea lasts more than a day or two, if you have severe abdominal pain, or if you have a fever of 102 degrees Fahrenheit or higher, if you have blood in your stool or if your stool appears black and tarry, or if you have signs of dehydration. Signs of dehydration include thirst, infrequent or no urination, dry skin, high fever, listlessness, or irritability.

If your child has diarrhea, do not hesitate to call your health care provider for advice. If the child shows no improvement within 24 hours, has stools containing blood or pus, or has a temperature above 101.4 degrees Fahrenheit, contact your health care provider immediately. Because a child can die from dehydration within a few days, contact your health care provider at once if you suspect your child is dehydrated.

Q. What is foodborne illness and what are the symptoms?

Foodborne illness, also known as food poisoning, can be caused by a variety of microbes such as bacteria, fungi, viruses, and parasites.  Harmful toxins or chemicals present in food also may cause foodborne illness.

Different causes of food poisoning cause different symptoms, so there is no one syndrome that is foodborne illness; however, common symptoms include abdominal cramping, diarrhea (which may be bloody), nausea, vomiting, fever, headache, fatigue, and body aches.

Generally, after contaminated food is consumed there is a delay before food poisoning symptoms start. This delay is called the “incubation period”. The incubation period of a foodborne illness can range from less than an hour (which is rare) to days or weeks, and depends on the organism causing the illness and the amount ingested. This means that the last foods consumed before symptoms start are not always the source of a person’s illness.

O. Peter Snyder, Jr. Ph.D., with the Hospitality Institute of Technology and Management, prepared charts on the incubation period and symptoms for several causes of foodborne illness. Below are links to the detailed charts.



Q. What are the causes of diarrhea?

Diarrhea – loose, watery stools occurring more than three times in one day – is a common problem. There are many causes of diarrhea. Temporary diarrhea lasting three weeks or less could be a symptom of a foodborne illness and is usually related to bacterial, viral, or parasitic infection. Temporary diarrhea may also be caused by food intolerances, food allergies, or reactions to medicines.

Chronic diarrhea lasts more than three weeks and is often related to disorders like irritable bowel syndrome or diseases such as inflammatory bowel disease or celiac disease. Some people develop diarrhea after stomach surgery or after removal of the gallbladder. In many cases, the cause of chronic diarrhea cannot be found.

Q. What is the stomach flu?

Many people use the term “stomach flu” or “24-hour flu” to describe symptoms of nausea, vomiting, or diarrhea. Although these symptoms can be related to illness caused by influenza viruses, experts at the Centers for Disease Control and Prevention suspect that many of the intestinal illnesses commonly referred to as “stomach flu” are actually caused by foodborne pathogens. Influenza or “the flu” is primarily an illness of the respiratory system caused by influenza viruses that are spread from person-to-person through coughing or sneezing. If diarrheal symptoms do not occur with respiratory symptoms, a person may actually have food poisoning.

Q. My doctor said I had “acute gastroenteritis”.  What does this mean?

Technically, gastroenteritis refers to irritation of the stomach and intestines. Health care providers frequently use “gastroenteritis” or “acute gastroenteritis” as nonspecific terms to describe diarrheal illness suspected to be caused by an infectious agent. Other symptoms can include abdominal cramping, diarrhea, nausea, vomiting, and fever.