Everyone can get a stomach ache or a mild case of diarrhea from time to time, typically caused by eating unusual or spicy foods, or overeating. Some people tend to ignore those symptoms, but you need to know that they can also be an indication of a more serious illness that needs to be caught early such as an E. coli infection.

What Is E. Coli?

E. coli is a type of bacteria that live in the intestines of humans and animals. Most types of E. coli are harmless and contribute to the health of the intestinal tract. However, some strains can make you sick, causing anything from stomach pain and diarrhea to life-threatening illness.

You can be exposed to the type of E. coli bacteria that cause illness by eating contaminated food or water, and by contact with a person or animal that is infected with the bacteria.

E. coli is transmitted through fecal contamination. Therefore, it can be transmitted from person to person if the infected person doesn't wash their hands thoroughly after going to the bathroom. The bacteria can also be found in an animal's fur and can also be transmitted if a child pets an infected animal, and then puts their fingers in their mouth.

Stages and Types of E. Coli

There are many strains of E. coli bacteria, but the ones that cause problems are those that produce a toxin that causes many symptoms. E. coli0157 is the most common type of these illness-generating bacteria found in North America.

The Centers for Disease Control (CDC) estimates that there are approximately 95,000 cases of E. coli infection in the U.S. each year. Obtaining exact numbers is difficult because some people don’t seek medical care for the condition, and physicians don’t always conduct the needed tests to diagnose infections.

Symptoms and Causes

Typically, you contract an E. coli infection by eating or drinking something that is already infected. Hamburger is the only type of meat that usually carries E. coli bacteria. If improper methods are used during slaughter and processing, or an accident occurs, hamburger meat can become contaminated as it is being packaged. 

Hamburger is also handled extensively before it's eaten. If the person forming the hamburger patties hasn't sufficiently washed their hands and has E. coli bacteria on them, they can create a hamburger patty that is contaminated all the way through.

Unlike many other types of bacteria, even a minuscule amount of E. coli bacteria can cause an infection. For example, if you eat a hamburger that is slightly undercooked, or if you swallow a mouthful of water from a contaminated swimming pool, you could develop an E. coli infection. Here are the most common ways you could be exposed:

  • Undercooked ground beef
  • Unpasteurized milk or juices
  • Contaminated fresh produce such as spinach and lettuce
  • Water in streams, rivers, lakes, and swimming pools can be contaminated when human or animal fecal matter builds up, although a substantial amount of E. coli bacteria is required to cause illness.

Widespread outbreaks of the infection have occurred in the United States. In 2016, there were three outbreaks caused by commercially produced beef products, flour and alfalfa sprouts.

Keep in mind that E. coli bacteria can be transmitted through personal contact. For example, parents often get sick from contact with their children who have the infection.

You can start to experience symptoms of an E. coli infection anywhere from one day to one week after exposure. Healthy adults usually recover from an E. coli infection within a week to 10 days. The bacteria will be eliminated from the body through defecation, for example, and your body will heal on its own. Symptoms include:

  • Mild diarrhea
  • Stomach tenderness, pain or cramps
  • Nausea and vomiting
  • Fever

Young children and older adults are more susceptible to developing severe blood and kidney problems from the E. coli toxins. However, severe symptoms only occur in 5-to-10 percent of the people exposed to disease-causing E. coli bacteria. Severe symptoms include:

  • Severe bloody diarrhea
  • Anemia, a reduction in the amount of oxygen produced in red blood cells
  • Weakness, lightheadedness, and/or lack of energy
  • Reduction in the amount of urine passed
  • Small dark patches on the skin
  • Nervous system problems, including irritability and seizures

If you develop any of these symptoms, contact your doctor immediately.

It’s possible that these severe symptoms can lead to kidney failure, coma, an inability to move one side of the body, blindness and death. Make sure to monitor anyone who has a confirmed case of E. coli infection to ensure you spot these severe symptoms right away.

Prevention and Risks

You can reduce your risk of being exposed to the E. coli bacteria by following some easy guidelines.

  • Cook hamburger meat until it reaches 160 degrees. When hamburger reaches that temperature, you won’t see any pink color. (Unfortunately, if you like your hamburgers pink in the middle, there's nothing you can do — it's always going to be a gamble.)
  • Be careful when grilling hamburgers. They can turn brown on the outside without cooking all the way through.
  • Drink pasteurized beverages such as milk, juice, and cider. If you purchase juice in a box or bottle kept at room temperature, the label may not state that it’s pasteurized, but typically it is.
  • Wash produce, especially leafy greens, thoroughly to reduce the possibility of bacteria clinging to it.
  • Use hot soapy water to wash knives, countertops, and cutting boards before and after you use them for raw meat or fresh produce.
  • Separate raw and cooked foods. For example, use one cutting board for raw meat and another for other foods such as vegetables. Also, put cooked meat on a different plate than the one you used for raw meat.
  • Wash your hands regularly. Wash your hands after preparing or eating food, changing diapers, using the restroom, or being in contact with animals. It is particularly important for children to keep this in mind.

Children and older adults are at a higher risk of developing the more severe problems associated with E. coli infections. Other risk factors include:

  • Immune systems weakened by an infection, cancer drugs, illnesses such as AIDS, or having had an organ transplant.
  • Eating potentially hazardous foods such as undercooked hamburger, unpasteurized drinks, and soft cheeses made from raw milk.
  • Low stomach acid levels. When you take a medication like Nexium or Prilosec to lower stomach acid, you lower your defenses against the E. coli bacteria.

Diagnosis and Tests

If you experience any of the symptoms of E. coli infection, check with your primary care physician immediately. If you have diarrhea that lasts more than two days without a reasonable explanation, there could be other causes such as the stomach flu. However, a visit to your doctor could help you avoid further complications if it turns out that you have an E. coli infection.

Your doctor will request a stool sample, and then send it to a testing laboratory. The laboratory will determine if the E. coli bacteria is present. In some cases, the bacteria may be cultured to identify the specific toxins that are being produced.

Treatment, Procedures, and Medication

The treatment for people with less severe symptoms of an E. coli infection is typically getting lots of rest and drinking plenty of liquids to prevent dehydration. Currently, no treatments or drugs are available to cure the infection.

You shouldn’t take anti-diarrheal medication because you will prevent your body from expelling the bacteria and toxins. Your doctor probably won’t prescribe antibiotics since those medications can make your symptoms worse.

If you develop severe symptoms from an E. coli infection, you will be undoubtedly be hospitalized. In the hospital, doctors can monitor your symptoms. They’ll also provide treatments to help your body cope such as IV fluids, blood transfusions, and kidney dialysis. 

Healthy Lifestyle Tips

As described under the heading Prevention and Risks, there are things you can do to help prevent exposure to the E. coli bacteria. You should also do your best to maintain a healthy immune system:

  • Stay smoke-free.
  • Eat a healthy diet that includes fruits, vegetables, whole grains, and low saturated fats.
  • Exercise on a regular basis.
  • Maintain a healthy weight.


It’s not difficult to be exposed to the type of E. coli bacteria that cause infections, but following some simple guidelines will help you reduce your risk. And, when you understand the symptoms to watch for, you can get the medical advice and care you need to help avoid serious illness.