Norovirus may be the culprit for an illness outbreak at the Monical's Pizza in Washington.
The Tazewell County Health Department says three laboratory-confirmed cases of norovirus infection were identified as of Wednesday afternoon.
An investigation show the virus was transmitted through high-touch surfaces.
Norovirus symptoms include vomiting and diarrhea. People reported symptom onset between Nov. 21 and Nov. 26. The CDC said the virus is commonly called "food poisoning" or "stomach flu," though those terms are misnomers.
More than 150 people reported illness after eating at Monical's. The restaurant closed over the weekend on the health department's recommendation. A spokesperson for the chain eatery said the Washington underwent deep cleaning, food disposal, and staff training reinforcement before reopening on Tuesday.
