BLACK RIVER FALLS, Wis. -- Health officials are closer to knowing what made more than 200 people sick at a Jackson County lake.

The Jackson County Health Department and Forestry and Parks Department investigated reports of people becoming ill with flu-like symptoms after swimming in Lake Wazee July 4.

Christine Hovell, Jackson County Health officer, says nororvirus is a likely cause of the illnesses, due to fecal contamination found in water at the lake's popular beach.

Click here for more on norovirus.

Samples from a few of the sick swimmers are being tested at the Wisconsin State  Lab of Hygiene. Hovell says e-coli and blue-green algae do not appear to be factors.

Lake Wazee's beach will remain closed through the weekend. Hovell says warm temperatures and sunlight will help destroy the contaminants in the water.

Health officials will test the beach water on Monday to make sure the water is safe for swimmers.

Lake Wazee is a popular among scuba divers due to its depth and rocky ledges. Hovell says scuba divers should wash their equipment and hands thoroughly to prevent possible illness.

The beach's closing is also affecting profits for some local businesses in the area.

"Business has kind of dropped off with the snorkling and the beach comers," said Keith Cormican, owner of Wazee Sports Center. "We get a lot of traffic from those people and it definitely dropped right off."

The snorkling business accounts for about 30 percent of Cormican's profits.
It doesn't sound like much, but with a week's worth of profits taking a dive, the numbers add up.

"Our season's very short," said Cormican. "So a week is a lot for us. So we've just gotta tough it out, and let them do their thing out there, and make sure it's safe before they open it up again for all the beach comers."

So while everyone waits for the beach to reopen, Cormican hopes people will take this time to make sure the same thing won't happen again.

"If we can get people to respect what's out there, and clean up after themselves, and maybe not go out there if they're really sick, that would be very helpful," said Cormican.