To examine the incidence of Escherichia coli 0157:H7 enteric infections in the United States and to evaluate the vehicles of transmission for sporadic cases, we conducted a one-year, population-based study at a large health maintenance organization (HMO) in the Puget Sound area of Washington State. All stool specimens submitted for culture to the HMO laboratory were screened for E coli 0157:H7; the organism was identified in 25 (0.4%) of 6485 stool specimens. All patients with E coli 0157:H7 identified had diarrhea; 24 patients (96%) had bloody diarrhea. Exposure histories demonstrated that rare ground beef was consumed more often by patients (21%) than by age-matched control subjects (4%) in the week before onset of illness. Raw milk also was consumed by two patients but by none of the control subjects. Incidence rates for laboratory-confirmed enteric infections in the HMO population were as follows: Campylobacter, 50/100 000 person-years; Salmonella, 21/100 000 person-years; E coli 0157:H7, 8/100 000 person-years; and Shigella, 7/100 000 person-years. The organism is a more common pathogen in the United States than is generally recognized, and the diagnosis should be considered for patients with suspected enteric infection.
Kristine L. MacDonald, Michael J. O'Leary, Mitchell L. Cohen, Peggy Norris, Joy G. Wells, Elizabeth Noll, John M. Kobayashi, Paul A. Blake. Escherichia coli 0157:H7, an Emerging Gastrointestinal PathogenResults of a One-Year, Prospective, Population-Based Study. JAMA. 1988;259(24):3567–3570. doi:10.1001/jama.1988.03720240029030