In October 2011, approximately 200 persons attended a wedding reception held at the American Legion in Ashby, Minnesota on October 15. The next day people who attended the reception began to experience vomiting and diarrhea. Minnesota Department of Health (MDH) staff conducted an investigation.

Fifty-five wedding attendees were interviewed. Eighteen (40%) met the case definition. The median incubation period from the time of the recption was 37 hours (range, 28 to 59 hours). One case visited a medical provider; no cases went to the emergency room or were hospitalized. Everyone recovered. Two stool specimens from attendees tested positive for norovirus GII.

Food items served at the reception came from multiple sources. All of the foods were self-serve on a buffet line. No food item was significantly associated with illness.

A child was reportedly ill prior to the wedding reception and vomited at the church before the wedding ceremony. Both of the people who prepared food for the wedding reception were reported by others to become ill the evening of the wedding. The two food preparers could not be reached for interview.

Investigators concluded that one or more food items served at the reception were likely contaminated. Foods were most likely contaminated by a food preparer that was ill or in the incubation stage of illness. However, this was not confirmed, and person-to-person transmission could not be ruled out as the cause of the outbreak.