Swimmers' itch hits at local lakes

Swimmers' itch has resurfaced at area beaches.

Swimmers have reported getting irritating red bumps on their skin after dips at Seward Park, Magnuson Park, Matthews Beach Park and Juanita Beach Park.

King County posted signs this week at lakes warning people about the presence of schistosomes, transparent parasites that burrow into wet skin and die, causing a rash and itching sensation.

"It's not a life-threatening situation. It's an annoying situation," said county spokeswoman Carolyn Halley.

"It happens every year."

Sally Fox, a frequent Lake Washington swimmer who lives near Matthews Beach in Northeast Seattle, said this year's itch is the worst she has suffered in 14 years.

Sunday morning, she skipped Matthews Beach and swam off Magnuson Park because the water looked clearer.

After her swim, she rinsed in the outdoor shower and then showered again with soap at home. The parasites attacked her midriff anyway.

Schistosome eggs develop in the intestinal tract of a goose or duck and are excreted into the water.

The eggs hatch, and the parasites swim to the nearest snail shell, where they mature.

Snails shed the parasites at the beginning of summer, about the same time humans start sticking their toes in the water.

After leaving the snail, the parasite has 48 hours to swim to a goose or duck and start the cycle again.

It's not possible to eliminate the problem, Halley said.

"It's not about the water being dirty, it's a parasite," Halley said. "As long as the hosts are there, if there are geese at all, anybody who's been in the water is going to be susceptible."

Seattle lifeguards are being told to spread sunscreen on themselves to avoid swimmers' itch.

That tactic apparently works.

"Only one has had two little bumps of swimmers' itch, and it was a place she missed," said Seattle Parks spokeswoman Dewey Potter.

The following steps are recommended to avoid swimmers' itch:

Liberally apply a waterproof sunscreen prior to swimming.

Swim in deep water, because snails live primarily in shallow water.

After getting out of the water, dry off with a towel and remove wet clothes. Shower immediately with soap and water.

Do not feed waterfowl.