In a follow-up to a report about a week ago, The Whatcom County Health Department (WCHD) updated the information on their investigation into the shiga toxin-producing E. coli O157 outbreak in the county Tuesday.

Image/ National Atlas of the United States
Image/ National Atlas of the United States

The outbreak of E. coli is associated with the Milk Makers Fest that was held at the Northwest Fairgrounds in Lynden on 4/21 – 4/23/15. Over a thousand primary school children from all of the school districts in Whatcom County attended the event. Most of the cases involve children who attended the event. Several older children involved with the event and some adults and close contacts of cases have also become ill.

WCHD is continuing to interview cases to determine if there was a common food or water source or activity, such as the petting zoo or other contact with livestock.

Washington State Department of Health Communicable Disease Epidemiology is assisting with the outbreak investigation. Cumulative total: 22 cases (7 cases have been hospitalized), 20 probable cases.

The state public health lab is testing confirmed E. coli O157 isolates for serogroup (to determine if O157:H7 or another related serogroup). Preliminary positive O157 isolates are regrown and have further testing done at a commercial lab to confirm O157. We expect to get the first results of serogroup testing from the state public health lab this week.