The most common foodborne illnesses and how to prevent them

Written by Sarah Thebarge, Physician Assistant and Medically reviewed by Dr. Betsy Koickel, MD on April 17th, 2025

Foodborne illness, also known as food poisoning, is an illness that can strike at any time. Every year, one in six Americans will suffer some form of foodborne illness as a result of consuming raw meats, spoiled foods or contaminated raw produce. 

The most common foodborne illnesses are from improper home preparation or in restaurants where staff members might be ill or have prepared food in an unsanitary manner. Produce purchased at farmers' markets often has a higher risk of being contaminated through contact with farm animals or contaminated water.

It can be difficult to tell which foodborne illness you may be suffering from, its origin, and how to treat it. After all, there are over 250 bacteria, pathogens or viruses that can cause foodborne illness. Below, we discuss some of the most common foodborne illnesses, where they are often found, and when you should seek medical treatment.

E. coli

 Most often found in: undercooked beef, unpasteurized dairy products, raw produce

Escherichia coli bacteria (more commonly referred to as E. coli) are naturally occurring bacteria in the intestinal tract that support digestion.

However, some strains of E. coli, such as E. coli O157:H7, produce toxins that can cause infection or illness. The majority of E. coli outbreaks occur from June through September, although it is not entirely clear why. 

Causes

E. coli is often transmitted through contaminated water or foods (like undercooked beef or unpasteurized dairy) or contact with people or animals.

To minimize the risk of E. coli, thoroughly wash all raw produce, regardless of where it was purchased. Cooking your produce can also reduce your risk of E. coli infection. 

Cooking meat to the right temperature can also help reduce the risk. Thoroughly cook ground beef to an internal temperature of 160°F, poultry to 165°F, and other meats to a minimum of 145°F. 

Make sure to clean and disinfect any areas where food is prepared before and after preparation. 

Symptoms

For many people with E. coli, the food source of infection can be difficult to pinpoint as symptoms can begin anywhere from one to ten days after the initial contact. Symptoms include severe stomach cramps, vomiting, and diarrhea. These symptoms can last up to a week.

Those with weakened immune systems and those taking medication to control stomach acid are often more at risk for E. coli because the body is less able to protect itself. Young children, older adults and pregnant people may also be at higher risk for infection.

Salmonella

 Most often found in: Undercooked poultry, eggs, unpasteurized dairy products

Salmonella enterica are bacteria that cause an infection known as salmonellosis. Similar to E. coli, salmonellosis is more common in summer.  

Causes

Salmonella bacteria are transmitted via undercooked chicken or other poultry and unpasteurized dairy products. Raw eggs and foods containing raw eggs (hollandaise sauce, salad dressings, cookie dough and cake batter) may increase the risk of salmonellosis and should never be consumed raw. 

Salmonella can also be transmitted via direct contact with someone who has the bacteria or has prepared your food.

To avoid salmonella infection, make sure to prepare raw meats and produce on separate cutting boards to avoid cross-contamination of foods. Do not consume raw or undercooked eggs, poultry or meats.

Poultry items should be cooked to an internal temperature of 165 F. Ground meat should be cooked to an internal temperature of 160 F and other meats to a minimum of 145 F to kill salmonella bacteria. Make sure to clean and disinfect any areas where food is prepared before and after preparation.

Symptoms

Salmonellosis symptoms can present anywhere from 12 to 72 hours after initial contact, lasting between four to seven days. Symptoms include abdominal cramps, diarrhea and fever. Severe infections may cause high fever, lethargy, head and body aches and blood in urine or stool. 

Young children, older adults, people with compromised immune systems, and pregnant women may also be at higher risk for infection.

Noroviruses

 Most often found in: raw produce, shellfish, contaminated water

Noroviruses are one of the most contagious forms of foodborne illness. They are also the most common cause of foodborne illness, with experts estimating that half of all illnesses result from norovirus. 

Causes

These viruses can be communicated via direct contact with someone infected or simply by touching a contaminated surface. They are especially prevalent in daycare centers, nursing homes and cruise ships due to their confined quarters. 

Another common cause of noroviruses is contaminated water or foods that have been prepared by someone contagious. Raw shellfish and raw produce are two major sources of noroviruses. It is best to make sure these foods are washed and prepared properly to kill any viruses. 

Frequently wash hands with soap and water to prevent the spread of noroviruses. Make sure to clean and disinfect any areas where food is prepared before and after preparation. 

If you are ill with norovirus, avoid preparing food for others and stay home from work or school to avoid spreading the virus.

Symptoms

Norovirus symptoms can take 12 to 48 hours to present and typically last one to two days. Common symptoms include cramps, nausea, diarrhea, fever, headache and vomiting. Young children, older adults and people with compromised immune systems could be at higher risk for infection.

Campylobacter

Most often found in: undercooked poultry and meat, produce, unpasteurized dairy products 

 Campylobacter jejuni is a bacteria that causes an infection known as campylobacteriosis. It is the most common bacterial cause of foodborne illness in the United States and the most common cause of Guillan-Barré syndrome.

Causes

Campylobacter infections are often caused by eating raw or undercooked poultry or foods contaminated by raw poultry or meat. To avoid infection, cook poultry to a minimum internal temperature of 165 F. Ground meat should be cooked to an internal temperature of 160 F and other meats to a minimum of 145 F to kill bacteria.

Prevent cross-contamination by using separate cutting boards and knives for raw meat and produce. Make sure to clean and disinfect any areas where food is prepared before and after preparation. Wash hands with soap and water for at least 20 seconds after using the bathroom, preparing or eating food and handling raw or undercooked meat.

Symptoms

Symptoms of campylobacteriosis infections usually take two to five days to present and can last between three to six days. Common symptoms include diarrhea, abdominal pain, nausea, vomiting, headache, fever and abdominal pain. Older adults, young children, pregnant people and immunocompromised people are at high risk for complications.

Listeria

Most often found in: unpasteurized dairy products, raw sprouts, and melons 

Listeria monocytogenes (often shortened to listeria) is a bacteria that can cause an infection known as listeriosis. Listeriosis is one of the most severe foodborne illnesses but is relatively rare.

Listeria is often found in moist environments and is present in the soil, water and digestive tracts of animals.

Causes

Listeria is usually transmitted through foods with a long shelf-life under refrigeration or raw and unpasteurized foods. Avoid eating and drinking products made with unpasteurized milk to minimize the risk of listeriosis. Cook raw sprouts and deli meats thoroughly to kill any bacteria.

Reduce the risk of listeriosis from refrigerated foods by checking shelf-life dates, properly storing foods at their recommended temperatures and storing leftovers within two hours. Make sure to clean and disinfect any areas where food is prepared before and after preparation.

Symptoms

Listeriosis symptoms can present within hours or after two to three days of contact. Symptoms may last a few days or several weeks.

Listeriosis symptoms include fever, nausea, vomiting, diarrhea and muscle aches. Severe cases can cause additional symptoms, including headache, loss of balance, convulsions, stiff neck and confusion.

Children, older adults, pregnant people and immunocompromised people are at higher risk of listeriosis.

Why foodborne illnesses are on the rise

Foodborne illnesses are on the rise for several reasons. First are our global food supply chains and large-scale production, where food travels long distances and is mass-produced before reaching our plates. The travel time and handling allow for multiple opportunities for contamination.

Climate change may also play a role. Warmer climates encourage the growth of bacteria. There are also changes in dietary preferences, with more people choosing to eat raw foods, like sushi or greens, which have a higher risk of contamination.

Visit urgent care for foodborne illnesses

Not all types of foodborne illnesses require a visit to urgent care. However, some signs may indicate a severe illness that requires treatment.

Seek medical attention if you have a high oral temperature above 102 F, frequent vomiting that prevents keeping liquids down, signs of dehydration (such as dry mouth, little urination and dizziness upon standing), bloody diarrhea or diarrhea that lasts more than three days.

In urgent care, lab tests are often performed to diagnose the virus or bacteria-causing symptoms and determine the best treatment.

Most common foodborne illnesses have similar treatments, including rehydration, electrolyte replenishment and management of symptoms such as nausea and diarrhea to improve food intake.

Antibiotics are often unneeded for foodborne illnesses caused by bacteria but might be necessary for severe cases. Illnesses caused by viruses do not require antibiotics, and treatment typically focuses on improving symptoms.

If you are unsure if you or your family should seek medical treatment for a foodborne illness, it is always best to err on the side of caution and consult a medical professional.

Find an urgent care location near you today. You can walk in without an appointment or save your spot online. We’ll have you back to feeling better in no time.

FAQs

Here are some frequently asked questions about foodborne illness.

What is the most common foodborne illness?

The most common foodborne illness is norovirus. Other common illnesses include salmonella, E. coli and listeria.

What are the symptoms of foodborne illnesses?

Typically, foodborne illnesses affect the digestive tract, leading to vomiting, nausea or diarrhea. They may also cause fever, fatigue, dehydration or neurological issues. 

How do foodborne illnesses spread?

Foodborne illnesses spread through contaminated food, surfaces or contact with infected individuals. 

Who is most at risk for foodborne illnesses?

Children, older adults, pregnant women and those who are immunocompromised are most at risk of foodborne illnesses.

How long do foodborne illnesses last?

How long an illness lasts will depend on the specific pathogen. Most foodborne illnesses can resolve in 24-48 hours, but some can last weeks or months, depending on the severity.

What foods are most likely to cause foodborne illnesses?

Foods most likely to cause foodborne illnesses include:

• Deli meats and hot dogs
• Fresh produce that is not washed properly
• Prepared foods left at unsafe temperatures
• Raw or undercooked meat, poultry, eggs or seafood
• Unpasteurized dairy or juices

How can you prevent foodborne illnesses at home?

You can prevent foodborne illnesses at home by adhering to food safety practices. This may include:

• Cooking foods to the right temperature (use a thermometer)
• Disinfecting prepping and cooking surfaces
• Discarding spoiled or expired food
• Refrigerating foods promptly
• Thaw frozen foods appropriately
• Using separate cutting boards for meat and vegetables
• Washing hands regularly
• Washing fruits and vegetables thoroughly

When should you see a doctor for food poisoning?

You should see a doctor for food poisoning if you have blood in your stool, have been vomiting for more than two days or are showing signs of dehydration.

Are foodborne illnesses contagious?

Yes, some foodborne illnesses are contagious, especially those caused by norovirus, salmonella and E. coli. 

How can restaurants and food service workers prevent contamination?

Restaurants can prevent contamination by following food safety protocols. This may include:

• Cooking foods to the right internal temperature
• Ensuring proper refrigeration and storage
• Keeping raw and cooked foods separate
• Requiring sick employees to stay home
• Sanitizing surfaces and tools regularly
• Strict handwashing protocols

References:

1. https://www.cdc.gov/ecoli/about/index.html
2. https://www.ncbi.nlm.nih.gov/books/NBK555892/
3. https://www.cdc.gov/campylobacter/about/index.html
4. https://www.cdc.gov/listeria/about/index.html
5. https://pmc.ncbi.nlm.nih.gov/articles/PMC10205246/
6. https://www.foodsafety.gov/food-safety-charts/safe-minimum-internal-temperatures