PETOSKEY — When the summer temperatures heat up, so does the chance of getting cercarial dermatitis, commonly known as “swimmer’s itch.”
It’s a skin irritation that is caused by larval form of certain flatworms, which are parasites, that burrow into human skin, seeking to complete their life cycle.
Joshua Meyerson, medical director for the Health Department of Northwest Michigan, said the parasite, which is found in most lakes, is carried by droppings from ducks, geese, or other waterfowl. The parasites then move into snails where they mature, eventually coming out to re-infect more waterfowl. But as they float in the water, they can come in contact with humans and may burrow into the skin in an effort to survive. The parasites die quickly, but they can trigger an irritating rash.
Some lakes are more susceptible than others, including shallower lakes, such as Pickerel and Crooked lakes.
“I’ve heard some reports of swimmer’s itch so far this summer, but I wouldn’t call it a horrible year just yet,” said Kevin Cronk, monitoring and research coordinator at Tip of the Mitt Watershed Council in Petoskey.
“It has been a concern of many area lake associations in recent years, so I know there’s a lot of talk about it,” he added.
Tip of the Mitt Watershed Council in Petoskey recommends people do not feed waterfowl, since waterfowl may aggravate the problem by concentrating potential hosts in a limited area.
“The bottom line is keep your food to yourself,” Cronk said. “It just attracts waterfowl to your property or to the beach, and if you’re feeding them, and they remain in the area, you know there is going to be bacteria in the water.”
Swimmer’s itch is children is common, since youngsters tend to stay in shallow areas of the beach, making them more susceptible.
Symptoms of swimmer’s itch include intermittent periods of itching that continue for several days. After about 24 hours, the reddened areas reach their largest size, and the spots are often confused with other bug bites, such as mosquitoes, or may be misdiagnosed as poison ivy.
Meyerson said his best advice to avoid swimmer’s itch is to not spend much time wading in shallow areas, and if possible, rinse off soon after swimming. You can also vigorously towel dry to rub those parasites off the skin.
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