The below is the Press Release directly from the Weber-Morgan Health Department. Although the vector of the illnesses seems to be lettuce, it is most likely that the cause was not directly lettuce, but cross-contamination between hamburger and lettuce – See earlier post Another Wendy’s E. coli Outbreak?
Weber-Morgan Health Department (Utah)
AUGUST 7, 2006
Infectious Agent: E. coli O121:H19
The Weber-Morgan Health Department confirms that four people have contracted an E.coli O121:H19 infection with three of these people developing the more severe case of hemolytic uremic syndrome (HUS). Based upon the findings of our investigation, we have concluded that the probable source of the contamination was iceberg lettuce prepared at the Wendy’s Restaurant at 2500 N. 400 E. in North Ogden.

We believe that people may have been exposed to the contaminated lettuce between the period of June 27th and June 30th, 2006. One of the confirmed HUS cases (Case A) ate cheeseburgers with lettuce at the Wendy’s Restaurant for three consecutive days, June 27th through the 29th. On June 30th, Wendy’s catered a salad luncheon at the CORE Academy Conference held at Orion Junior High School in Harrisville where more than 300 attendees were potentially exposed. A second confirmed HUS case (Case B) attended this conference, only on Friday, June 29th 2006, and ate the Wendy’s salad.
A second attendee (Case C) of the conference was also confirmed to have an E.coli infection. Case A and Case C were both confirmed with identical genetic strains of E.coli O121:H19. The only common exposure shared by these three cases was the iceberg lettuce. The third HUS case (Case D) was determined to be a secondary transmission from a self reported infected person who attended the conference.
The Weber-Morgan Health Department determined that the conference attendees represented a known exposure group. We wanted to establish the extent of illness among these attendees, and to determine if secondary cases had occurred. Through the means of a phone bank, we contacted 75% of those who attended the conference. Even though self-reported illness occurred, we were unable to establish any clinically confirmed E.coli cases among the respondents.
Part of our investigation included a thorough inspection of three food establishments that catered to the conference. No significant food code violations were observed. The only common food item shared by cases A, B, and C was iceberg lettuce from Wendy’s. We believe that the source of this food borne contamination was limited to this one Wendy’s restaurant.
From the time the Weber-Morgan Health Department was first notified of the initial HUS case, we quickly determined that there was no immediate or ongoing threat or risk to the public’s health. Otherwise, we would have immediately closed the restaurant in question, and alerted the public.
We believe that this disease outbreak is over. The transmission of this illness is a rare event, and knowing the incubation period of 2-8 days and the time that has elapsed from the initial occurrence, we believe that the possibility of any additional cases is very remote.