(INDIANAPOLIS) -- A norovirus may have caused hundreds of people to become sick last week after eating at an Olive Garden restaurant, a health official said Monday.
The restaurant on the city's north side, which remained closed Monday, was free to reopen after being shut down for cleaning over the weekend, said John Althardt, a spokesman for the Marion County Health Department.
Stool samples from three restaurant employees and one patron tested positive for a norovirus, which can cause symptoms of nausea, vomiting and diarrhea, he said.
Outbreaks of noroviruses have taken place in restaurants, cruise ships and other places where people eat food handled by others, according to the Centers for Disease Control.
The health department was still working to pinpoint the exact source of the illnesses, Althardt said.
Althardt said the Olive Garden restaurant was cleaned thoroughly over the weekend and that it could reopen Monday. Health officials talked to restaurant managers and stressed that they should not allow sick employees to work.
"We talked to them extensively about employees washing their hands, especially after using the restroom," Althardt said.
More than 300 people complained of being ill after eating at the restaurant, health officials said. The restaurant was closed on Friday.
(Copyright 2006 by The Associated Press. All Rights Reserved.)