CLEVELAND, Dec 25, 2007 (AP): The Cuyahoga County health board warns a highly contagious stomach flu has hit northeast Ohio.

Chris Kippes, director of disease investigations, says so far this month there have been six outbreaks of the gastrointestinal illness norovirus in the area. Outbreaks have been concentrated in hospitals, day-care centers, schools, and one restaurant—Blake’s Seafood Restaurant & Bar in the Cleveland suburb of Chagrin Falls.

Experts say the sickness, also known as the “Cruise Ship Virus,” typically peaks this time of year. Symptoms include about two days of nausea, vomiting, and diarrhea.

Noroviruses descend from the Norwalk virus, named after a huge outbreak of gastrointestinal illness in Norwalk, Ohio, in the late 1960s.

The Ohio Department of Health has recorded 71 norovirus outbreaks in 2007.