Mystery Stomach Bug Shuts Down Washington Lake

A mysterious stomach bug has shut down a lake in Kitsap County, Washington, where more than 200 weekend swimmers are coping with cramps, nausea and diarrhea.

Health officials are calling the outbreak at Horseshoe Lake "norovirus-like" as they await test results, according to a statement from the Kitsap Public Health District. The number of sickened swimmers was revised to 202 today, up from 20 Monday.

The lake has been close until further notice.

"Although there is no laboratory confirmation of a specific virus or bacteria responsible for the illnesses at this time, Public Health and Kitsap County are issuing the temporary closure as a precautionary measure while they investigate and to protect the public and prevent any additional illnesses," the statement reads.

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Norovirus is highly contagious, spreading through food, liquid and surfaces that are contaminated with infected feces or vomit, according to the U.S. Centers for Disease Control and Prevention. There's no specific treatment, so the CDC recommends staying hydrated for the duration of symptoms, which is usually one to three days.

Kitsap County health officials are asking people who visited Horseshoe Lake between July 10 and July 13 to report any symptoms to the Public Health District and seek medical attention if they persist for more than 24 hours. They're also urging "diligent and frequent hand-washing with warm water and soap" to prevent the spread of the illness.

Check back here later today for more information on the outbreak.