Escherichia coli ( E. coli ) infection is caused by a bacteria. It is the leading cause of bloody diarrhea. This type of infection may need medical attention. Contact your doctor if you think you may have it.


This infection is caused by some types of the E. coli bacterium. Most E. coli infections are caused by:

  • Eating undercooked beef, especially ground beef
  • Drinking contaminated water
  • Drinking unpasteurized milk
  • Working with cattle

Digestive Pathway Through Stomach and Intestines

Digestive pathway
© 2009 Nucleus Medical Art, Inc.

Risk Factors

The following factors increase your chance of developing E. coli infection:

  • Age: children and older people
  • People with another illness
  • Working with cattle
  • Living in northern states



Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include:

  • Stool culture—to find out if you have E. coli O157:H7 in your intestines


Talk with your doctor about the best plan for you. Treatment options include:

Fluid Replacement and Monitoring

Most people will get better in 5-10 days. They rarely need a specific treatment. Avoid medicine that stops diarrhea. Drink plenty of water and fluids. Fluids through an IV line may be needed in cases of severe dehydration .

Treatment for Hemolytic Uremic Syndrome (HUS)

HUS is a life-threatening condition. It occurs in some people with E. coli infection. HUS may need to be treated with blood transfusions and kidney dialysis . Symptoms may include:

  • Pallor, tiredness, and irritability
  • Small, unexplained bruises, or bleeding from the nose or mouth—caused by problems in the body’s clotting mechanism

Kidney Dialysis

Dialysis pump
© 2009 Nucleus Medical Art, Inc.

If you are diagnosed with an E. coli infection, follow your doctor's instructions.


To help prevent E. coli infection:

  • Cook all ground beef and hamburger thoroughly.
  • Avoid eating undercooked hamburger or other ground beef.
  • Keep raw meats separate from ready-to-eat foods.
  • Wash hands, counters, and utensils with hot soapy water after they are exposed to raw meat.
  • Drink only pasteurized milk, juice, and cider.
  • Wash fruits and vegetables under running water.
  • Drink municipal water that has been treated with a disinfectant (eg, chlorine).
  • Wash hands after bowel movements and after changing soiled diapers.