In September 2011, the Minnesota Department of Health (MDH) investigated an outbreak of norovirus among people who attended a wedding reception in Lakeville, Minnesota on September 10. The plated dinner was held at and catered by a restaurant.

Sixty-four wedding guests were interviewed. Thirty-five guests met the case definition. The median incubation period was 38 hours (range, 12 to 61 hours). One case visited an emergency room and was hospitalized. Stool samples were collected from 5 wedding guests from 4 households. All five stool samples were positive for norovirus GI.

By univariate analysis, eating chicken from the plated dinner (35 of 35 cases vs. 18 of 23 controls; odds ratio [OR], undefined; 95% confidence interval [CI], 2.1 to undefined; p = 0.01), and drinking
ice water (24 of 34 cases vs. 9 of 23 controls; OR, 3.7; 95% CI, 1.2 to 11.6; p = 0.04) at the reception were significantly associated with illness. Neither variable was significantly associated with illness by
multivariate analysis using logistic regression.

Nineteen restaurant employees were interviewed; none reported gastrointestinal illness in the several weeks prior to the wedding. One employee reported having a child with diarrhea onset 5 days prior to the wedding reception. This employee reported using bare hands to garnish plates with parsley for the reception. Environmental health specialists evaluating the restaurant noted that a cook did not wash their hands prior to beginning to prepare food. No other violations were noted.

Employee hand contact with meal items, including parsley garnish and water glasses, is a plausible source of illness. However, the ultimate source of contamination was not identi􀂿 ed.