An individual who recently swam at Deer Lake on Whidbey Island has caught swimmer’s itch, according to an announcement from Island County Public Health sent Thursday, Aug. 31.

According to the Centers for Disease Control and Prevention, swimmer’s itch is caused by parasites that infect aquatic snails. This causes the snails to release a different type of microscopic larvae into the water, which swims away to find a host — usually birds, muskrats and raccoons.

In this case, despite the fact humans aren’t suitable hosts, these larvae burrowed into the skin of a human.

This condition appears as a skin rash, and may cause tingling, burning or itching of the skin, small reddish pimples and small blisters. These symptoms may appear within minutes or days after being exposed.

The more often one swims into contaminated waters, the faster and more intense the swimmer will develop more serious symptoms, the CDC warns.

Authorities recommend avoiding the lake, toweling dry or showering immediately after leaving the water, and not attracting birds into swimming areas. When symptoms develop, the CDC recommends not to scratch the rash.

It is not contagious, and it can be treated with over-the-counter remedies, like corticosteroid cream, baking soda, or an anti-itch lotion.