Escherichia coli are very common bacteria — mostly harmless — that exist in the environment, in foods and in the intestines of people and other animals. Some strains, however, such as Shiga toxin-producing E. coli (STEC) can cause diarrhea, stomach cramps and vomiting. Other strains can cause urinary tract infections, pneumonia and other respiratory illnesses or acute illnesses. About 5-10% of people with STEC infections can develop hemolytic uremic syndrome about a week after symptoms first appear. This life-threatening condition requires hospitalization to prevent kidney failure and other complications.
One of the most important ways to prevent E. coli illness is hand hygiene, particularly after the bathroom, changing diapers or contact with animals or their environments. Other preventive measures include thoroughly cooking meats, avoiding raw milk, avoiding cross-contamination between raw meat and other foods while preparing food, and not swallowing water when in lakes, ponds, streams and swimming pools, including kiddie pools.