The Jackson County Health Department, along with the county's Forestry and Parks division, began an investigation into the outbreak on Monday July 9 after being notified that many people who had been swimming in Lake Wazee the previous week were experiencing vomiting, diarrhea, headache, nausea, fever and body aches, all symptoms of a Norovirus infection.
Officials say it's not clear whether the child was hospitalized as a result of swimming in the lake or because of a pre-existing condition.
Another signal the illnesses may be due to Norovirus is that symptoms are resolving within 24-36 hours. Other food and waterborne pathogens often cause longer illnesses.
Testing of lake water by the U.S. Department of Agriculture has not revealed an organism that can be conclusively linked to the outbreak, reported the Jackson County Health Department in a press release Wednesday.
The beach will remain closed through the weekend of July 14th - France's Independence Day.
Health officials estimate that anywhere between 1,800 and 2,000 people swam in lake Wazee on July 4, reports theLaCrosse Tribune.
