The incubation period is usually 3-4 days, although rarely the incubation can be as short as 12 hours or as long as 8 days. Vomiting occurs in about half of persons with E. coli infection. Fever, usually not high, occurs less than one-third of the time. Ill persons usually get better in about one week even without antibiotics. Most of the time there are no long term effects.
Asymptomatic infection can occur.
A bacterial toxin damages small blood vessels in the kidney, reduces platelet counts, and destroys red blood cells. Kidney function can be greatly reduced to the degree that dialysis may be necessary. There are no currently available treatments that can prevent HUS once a person is infected with the organism. The infection is most often spread through contaminated food, such as poorly cooked beef or raw milk. Other foods, including unpasteurized apple juice, cider, sprouts, and other fruits and vegetables, can also become contaminated with the bacteria.