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Swimmer’s itch showing up at a number of northern Iowa Lakes

SPIRIT LAKE – Swimmer’s itch is starting to make its presence known in the Iowa’s Great Lakes and surrounding northwest and north central Iowa lakes.

The condition, common in clear water lakes around the world, is caused by a microscopic parasitic flatworm. The flatworm eggs are transferred to water by bird droppings. The eggs hatch and infect snails, from which the free swimming form of the flatworm larvae emerges. Without a suitable host such as a bird, the parasite will try to penetrate the skin of humans, and quickly dies after that, causing an allergic reaction and itchy rash.

To help prevent swimmer’s itch, avoid swimming or wading in marshy areas where snails are commonly found, reduce the amount of time in the water, avoid beaches that have been pounded by waves over the past few days and quickly rinse or dry off when after getting out of the lake. Use of waterproof sunscreen has been reported to help protect skin from swimmer’s itch.

The welts and itching caused by the little parasitic pest can last for several days to about a week and usually don't require a visit to the doctor. You can treat the affected areas with an antihistamine along with calamine lotion.

Visit the following websites for more information on swimmer’s itch: