Warm weather means ‘swimmer’s itch’ parasite coming to a lake near you

Swimmers itch. From Washington State University.

SEATTLE, Wash. — Ahh, summertime.

Nothing better than busting out the floaties, heading to the lake and getting infested with tiny worm-like parasites.

Wait, stop.

Schistosomes, the parasite commonly called “swimmer’s itch,” are quite a problem in Washington’s waters, doctors with Washington State University’s Elson S. Floyd College of Medicine said. And while not dangerous, a bad case of swimmer’s itch can certainly ruin a summer day.

"They penetrate the skin and trigger an immune response in the form of red spots that can persistently itch," Dr. Jennifer Troiano said.

Swimmer's itch parasites are often found in healthy freshwater lakes. They spend their life cycles moving from small snails to ducks or geese. When the weather gets warm and the water heats, they become more active in shallow waters.

In their active time, they often mistake human legs for the skin of a duck or goose.

Dr. Dawn Dewitt said she came down with a nasty case of swimmer's itch on a vacation to Maine. She said one of the first things you can do if you start itching is get out of the water.

"If you notice an itch, it's time to get out," Dewitt said.

Drying off with a towel immediately after getting out of the water can help your chances of avoiding swimmer's itch, Dewitt said.

Red spots usually appear about one or two hours after the little worm-like parasite burrows into the skin. The severity of itching depends on each person.

The parasite doesn't live very long; only about 24 hours in a human.

Certain sunscreens can help protect against the itch. If you do fall prey, cool compresses, bathing in Epson salts and antihistamines can help quell the discomfort

Of course, people shouldn't avoid going in the water just to avoid the parasite. It's summertime. It's not too serious, other than some itching.

But do remember to dry off, Dewitt said. And it's best not to think of the parasites burrowing.