Updated January 2008

What Is E. Coli O157:H7?

E. coli O157:H7 are bacteria found in the intestines of cattle and other animals.  E. coli O157:H7 can cause serious gastrointestinal illness if food or water contaminated with these bacteria is consumed.

What Are the Symptoms of E. Coli Infection?

Symptoms can include severe stomach cramps, nausea, vomiting, diarrhea, bloody diarrhea, or fever (rarely), and usually develop within two to ten days after ingesting the bacteria.  Some people may have very mild symptoms, but they can still spread the infection to others.

How Serious Is the Infection?

Most people recover fully from the infection.  There is a risk of developing a serious kidney complication that can be fatal.  Less than 10% of people who see a doctor for this infection will develop the kidney complications.  Young children and the elderly are at greater risk for complications.

How Is E. Coli Spread?

E. coli is spread through the consumption of contaminated food or water.  E. coli is found in feces, and can spread from person to person by poor hand washing and improper food handling.  E. coli does not survive in the air, on surfaces like tables or counters and is not spread by coughing, kissing or normal, everyday interactions with friends and neighbours.

Is There a Treatment for the Infection?

People who are experiencing symptoms should seek medical attention.  Antibiotics are not recommended for this illness.

How Do You Prevent E. Coli Infections?

  • Cook ground beef thoroughly to an internal temperature of 71°C or until the juices run clear and the meat is no longer pink.
  • Drink only pasteurized apple cider and milk. Never let young children sample milk produced directly from a cow or other animal.
  • Wash all fruits and vegetables before eating.
  • Thorough hand washing is always a good practice. Make sure hands are washed with soap and water after using the toilet, handling diapers, pets, livestock and before preparing food as well as before eating food.
  • Clean and sanitize countertops and utensils after contact with raw meats and poultry.
  • Use separate work surfaces and utensils for preparing raw and cooked foods.
  • Keep cold foods at 4°C or lower. Keep hot foods at 70°C or higher.
  • Do not drink water from open streams and lakes.
  • If ill with diarrhea, avoid preparing or handling food for others. If employed as a food handler, daycare or health care worker, report any symptoms to your manager.

More Information

Call Toronto Public Health at 416-338-7600 (TTY at 416-392-0658) or speak to your healthcare provider.