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Swimmers itch parasites remain active in Alberta lakes

Swimmers itch is caused by an allergic reaction people have to the parasite.
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HE KNOWS THE ITCH - Patrick Hanington

With summer days stretching out before Albertans for another month the plethora of lakes and beaches continue to beckon, swimmers need to remain aware of a parasite that causes swimmers itch is also taking advantage of the water.

Swimmers itch is caused by an allergic reaction people have to the parasite. It looks like a rash or gathering of mosquito bites, pimples or blisters on the skin.

Patrick Hanington, assistant professor with the School of Public Health, who has studied parasitic immunology and swimmer’s itch both in Alberta and around the world since 2008, says swimmers itch is not a great medical concern and it is fairly easy to treat the itching sensation.

“We tend to tell people the best thing to do . . . use any over the counter anti-itch creams,” said Hanington. Mosquito bite treatments such as After Bite also help.

While the methods do not actually get rid of the rash, which clears up on its own, it will help with the itching. “They'll help you survive for the couple of days you have it,” said Hanington.

For individuals to lower their chances of developing swimmers itch Hanington advises they stay away from vegetative areas where snails live. The parasites are released from the snails and sometimes mistake humans as a permanent host, infecting them.

“Because the parasites are released from the snails . . . they're dictated by the water movements,” said  Hanington. He says this makes it difficult to determine when and where swimmers itch could be a problem.

Since May 2015 30 Alberta lakes have had reports of swimmer’s itch, including Pigeon Lake, Sylvan Lake, Wabamun Lake, Lake Bonavista, Lac St. Anne and Buck Lake.

When it comes to preventing swimmers itch Hanington stated there is a lot of information available on the Internet but not all of it is accurate. Toweling off as soon as one comes out of the water is a popular opinion but Hanington says the parasites can affect some faster than others. “We found you can get a rash as quickly as 10 minutes after being out of the water.”

Waterproof or sport sunscreen acts as a sticky barrier that helps prevent the parasites from getting to people's skin, says Hanington.

Swimmers itch can become more serious if a person opens the rash through scratching, a secondary infection could develop. Hanington says if a person is infected more than once their second and following reactions could be worse than the primary.