Managerial Epidemiology: Assignment Week 4

“Gastroenteritis following a retirement party at the State Capitol” 1 Outbreak Summary Approximately 300 persons attended a retirement party at the Nebraska State Capitol held on May 27, 2017. Most of the attendees worked in the Capitol. A private caterer (Caterer A) prepared and served food for the reception. Based on initial telephone interviews of persons reporting illness, the predominant symptoms were nausea and diarrhea, and the incubation period was approximately 24-30 hours. The following foods were served at the retirement reception: Swedish meatballs, taco dip, crab dip, a vegetable tray and herbed ranch dip, cake, nuts and mints. The vegetable tray consisted of cucumbers, broccoli, cauliflower, carrots, celery, green peppers, and radishes. All foods were prepared onsite on the day of the reception with the exception of the nuts, which were purchased by a coworker, and the mints, which were made by a coworker. The Swedish meatballs consisted of ground beef, ground pork, sour cream and flour. The meatballs were cooked twice. The taco dip contained layers of cream cheese mixed with salsa, ground beef, tomatoes, lettuce, onion, cheese and salsa. The taco dip was prepared manually by Caterer A in the kitchen at the State Capitol, and was not cooked after assembly. The crab dip contained canned real crab, cream cheese and ketchup. The investigators received completed surveys from 227 attendees. Of those 227 attendees, 128 (56%) persons reported a gastrointestinal illness within 72 hours of the reception. The average interval between time of food consumption and onset of illness was 32.3 hours (range 6 to 67 hours). Table 1 shows the symptoms reported by ill attendees. The duration of symptoms generally lasted 24 to 36 hours. One person reported being symptomatic for five days. Eight persons sought medical treatment, mostly for re-hydration therapy. Persons working in the security office at the State Capitol ate samples of the items served at the reception except the taco dip. None of the people from this office reported illness.