1. Take the Tummy Trouble Quiz
2. Digestive Disease Myths Slideshow Pictures
3. Ulcerative Colitis Slideshow

Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

View Full Profile

Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

View Full Profile

In this Article

• E. coli Facts
• What is E. coli?
• What is E. coli 0157:H7?
• Is E. coli 0157:H7 contagious?
• What are the symptoms of E. coli 0157:H7 infections?
• How is a E. coli 0157:H7 infection diagnosed?
• What is the treatment for E. coli 0157:H7?
• What are the complications of infection with E. coli 0157:H7?
• How do people contract E. coli 0157:H7 infections?
• E. coli 0157:H7 and prevention of outbreaks
• Other enterohemorrhagic E. coli strains (for example, 0145, 026:H11)
• Patient Comments: E. Coli - Symptoms
• Patient Comments: E. Coli - Treatments
• E. Coli 0157:H7 Index

E. coli 0857:H7 is infection is contagious and can be spread from person to person by fecal contamination.

Initial symptoms of E. coli O157:H7 infection

The initial symptoms of E. coli O157:H7 infection usually appear about three to five (though occasionally in as few as one day or as many as 10 days) after a person ingests the bacteria; the symptoms include

• nausea,
• vomiting,
• stomach cramps, and
• diarrhea that often is bloody.

The person may have a mild fever of about 100 to 101F (37.7 to 38.3 C). These symptoms can be seen in infected children and adults.

Later symptoms  E. coli O157:H7 infections

The majority of people (especially normal adults) are infected resolve the infection without antibiotics in about five to seven days. However, some people (about 10% of people infected, especially children under the age of 5 and the elderly) develop more severe signs and symptoms, and these people usually require hospitalization and aggressive treatment. These patients develop the usual symptoms listed above, but do not resolve the infection. They develop symptoms that last longer (at least a week) and, if not treated promptly, the infection may lead to disability or death.

These symptoms or complications fall into three main categories;

• Hemorrhagic (bloody) diarrhea: Hemorrhagic (bloody) diarrhea symptoms are an increased amount of blood in the diarrheal stool that does not seem to resolve and is usually accompanied by severe abdominal pain. Although this may resolve within a week, some individuals can develop anemia and dehydration that can cause death.
• Hemolytic-uremic syndrome (HUS): Hemolytic-uremic syndrome symptoms of pallor (due to anemia), fever, bruising or nosebleeds (due to destruction of blood platelets that are needed for blood to clot), fatigue, shortness of breath, swelling of the body, especially hands and feet, jaundice, and reduced flow of urine may be seen. HUS symptoms usually develop about 7 to 10 days after the initial diarrhea begins. HUS is the most common cause of kidney failure in children; children under 10 years old are the most likely to develop HUS. E. coli 0157:H7 produces toxins that damage the kidneys and destroys platelets that can lead to kidney failure, excessive bleeding, seizures or death.
• Thrombotic thrombocytopenic purpura (TTP): Thrombotic thrombocytopenic purpura is caused by the loss of platelets; however, the symptoms that occur are somewhat different and occur mainly in the elderly. The symptoms are fever, weakness, easy, rapid or "spontaneous" bruising, renal failure, and mental impairment that can rapidly progress to organ failures and death. Until the 1980's, TTP was considered a fatal disease, but since the 1980's, plasma exchange and infusion techniques have reduced the death rate in TTP patients to about 10%.

For most people (about 90%), the E. coli infection clears and a good outcome or prognosis occurs. However, if any of the above mentioned complications happen, the prognosis may range from good to poor. The variable prognosis depends on the severity of the complication, the quickness of diagnosis and treatment, the response of the individual to adequate treatment and the overall health of the individual. Children and the elderly are at higher risk for adverse outcomes.