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E. coli O157:H7 and other strains of E. coli that produce Shiga toxins are collectively known as Shiga toxing-producing E. coli (STEC).
Most strains of E. coli are harmless and live in the intestines of healthy animals and humans. STEC are strains of E. coli that produce a toxin and can cause severe illness.
People usually become infected with E. coli O157:H7 (STEC) by eating contaminated food
The organism can live in the intestines of healthy cattle. Eating meat (especially ground beef) that is rare or undercooked is the most common way of becoming infected. Drinking unpasteurized milk or juices, and drinking or swimming in sewage-contaminated water can also cause infection. The bacteria are present in an infected person's feces (stool) and may be spread from person to person.
E. coli O157:H7 (STEC) can cause severe bloody diarrhea and abdominal cramps
Sometimes infection causes nonbloody diarrhea or no symptoms. Symptoms begin 3 to 4 days, but can range from 1 to 10 days, after exposure. Hemolytic uremic syndrome (HUS) is a serious complication that occurs in some infected people, particularly children under 5 and the elderly. In this syndrome, red blood cells are destroyed and kidney failure occurs.
Infection can be diagnosed by detecting the bacterium in the stool
Your health care provider can request a special culture for E. coli O157:H7 (STEC) from a laboratory.
See your doctor if you think you may have this infection
Infection with E. coli O157:H7 (STEC) can be prevented by:
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