An Outbreak of Salmonellosis At a Large Fair in Washington State

In September 1985, surveillance of enteric illness at the Seattle-King County Department of Public Health detected an outbreak caused by Salmonella agona. The outbreak was associated with exposure to a food booth at a large annual fair in Pierce County, Washington. Members of the Tacoma-Pierce County Health Department and the Seattle-King County Department of Public Health conducted an investigation. Thirty cases were identified, with dates of onset between September 6 and 18. People who attended the fair were five times more likely to become ill than those who did not. Patrons of a single food booth were seven times more likely to become ill if they ate barbecue beef sandwiches. All cases either attended the fair or were food service workers for the itinerant booth and/or the restaurant supplying sliced beef to the itinerant booth. Conditions were found at the booth which could contribute to the spread and survival of salmonella.