In August 2011, Washington County Public Health & Environment (WCPHE) staff investigated an outbreak of gastrointestinal illness among wedding reception guests. The reception was held at a restaurant in Stillwater, Minnesota on August 26.

Illness histories and exposure information was obtained from 68 (39%) of the 175 wedding guests. Twelve individuals (18%) met the case definition. Of the 12 cases, 11 (92%) reported diarrhea, 6
(50%) reported cramps, 3 (25%) reported vomiting, and 3 (25%) reported low grade fever. The median incubation period was 7 hours (range, 3.5 to 14 hours). The median duration of illness was 35 hours (range, 27 to 53 hours). Due to delayed receipt of the wedding guest list and contact information, cases were unwilling to provide stool samples for analysis.

WCPHE sanitarians conducted an onset investigation on August 30 and 31. The walk-in and reach-in refrigeration units and corresponding stored food products were found to be out of appropriate temperature range. No ill food workers or associated household members were ill. No stool specimens were collected from food workers.

Investigators concluded the outbreak was most compatible with a bacterial intoxication, however, the etiology could not be confirmed. The outbreak most likely resulted from improper and prolonged cold holding at an inadequate temperature due to malfunctioning refrigeration equipment, creating a favorable environment for proliferation and survival of bacteria.