As of September 28, 2006, 187 persons infected with an outbreak strain of E. coli O157:H7 have been reported to CDC from 25 states.

Three cases have occurred in Washington State residents—one each in Cowlitz, Island, and Benton Counties . No outbreak-associated cases of E.coli O157:H7 infection have been identified in King County .

The outbreak is notable for high rates of hospitalization and hemolytic-uremic syndrome (HUS). Among the ill persons, 97 (52 percent) have been hospitalized, 29 (16 percent) have developed HUS, and an adult in Wisconsin has died. One hundred thirty-four (71 percent) were female and 18 (7 percent) were children under 5 years old. The proportion of people who developed HUS was 29 percent in children less than 18 years of age, 7 percent in persons 18 to 59 years old, and 14 percent in persons age 60 years or older. Typically, only about 8 percent of E.coli O157:H7 infections lead to HUS, and young children and the elderly are at highest risk.

Eighty-two percent of persons who reported an onset date became ill between August 19 and September 5. The peak time when illnesses began was August 30^th to September 1^st. 

E.coli O157:H7 infection typically begins with 1 to 3 days of non-bloody diarrhea which sometimes becomes bloody. Patients typically report significant abdominal pain and cramping. Fever is often absent or low-grade. Nausea, vomiting, and lethargy are also sometimes present. The incubation period is between 1 and 10 days.

Persons with suspected or confirmed E. coli O157:H7 infection should not be treated with antibiotics, as antibiotic therapy has not been shown to be of benefit and may be associated with an increased risk for HUS.

E. coli O157:H7 infection and HUS (regardless of E. coli O157:H7 culture status), should be reported immediately to Public Health at (206) 296-4774, day or night.