Westside Elementary School in Sauk County is shut down after dozens of students got sick. The students are suffering from vomiting, diarrhea and nausea. But, it's not the flu.

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The Sauk County Health Department said 70 students are sick and 10 percent are being testing for the Norwalk virus. The virus is highly contagious. It's passed from person-to-person contact if the infected person doesn't carefully wash his or her hands.

At a local baseball game near the school, some parents said they're not concerned.

"I don't know much about the disease, but I don't think it's that a big of a deal right now," said Rob Bautch, of Reedsburg.

"If it was something I was concerned about, I would keep him home from school and not expose him to the baseball," said Renee Nehring, of La Valle. "The game he's playing in now is every elementary school in the district."

Sauk County health officials said the symptoms might appear a day or two after infection. Recovery time is two to three days.

Westside Elementary will stay closed until after Memorial Day. School officials hope to reopen the school June 2. They said the virus should be dead and long gone at that time.

"Last night we had a crew go in and extensively clean up the facility, wipe down everything," said Tom Benson, Reedsburg School District superintendent.

In Wisconsin, 25 Norwalk outbreaks were reported in 2003. So far this year, 13 outbreaks have been reported.