Some people get the itch to swim in Alberta’s lakes. Unfortunately, some of those people get an itch from those swims, too.
Swimmer’s itch is a infection caused by parasites that pass from birds or mammals to snails, and then are shed into the water. Free again, they seek out other birds or small mammals, but will try penetrating a human’s skin if given the chance.
“A person isn’t a suitable host, so the immune response will produce an inflammation. So you’ll get an itchy red spot wherever the parasites tried to penetrate; it’s kind of akin to a mosquito bite at that point,” said Patrick Hanington, an assistant professor at the University of Alberta’s School of Public Health.
Like those pesky mosquito bites, swimmer’s itch does not present a real health threat, but is a nuisance that can last for one or two weeks.
In an effort to help swimmers avoid the itch, Hanington and his team at the U of A have set up a website (www.swimmersitch.ca) to monitor instances of the infections in the province. He is hoping swimmers who contract the itch will use the anonymous online reporting tool to help map outbreaks and, hopefully, predict future outbreaks.
Hanington said there is no real historical data on swimmer’s itch, as it has never been a reportable condition.
“We don’t know very much about when the parasites that cause swimmer’s itch are really prevalent in the lakes, and then which lakes have which parasites in them.
“What we’re trying to put together is a risk map that people can use to predict when they’re going to be exposed most to each of these parasites in the province.”
Dozens of reports from across the country have been made on the website since late June. The most reports have come from Buffalo Lake near Stettler and Pigeon Lake west of Wetaskiwin.
There have been two reports from Cow Lake south of Rocky Mountain House.
Hanington said the goal is to inform people, rather than scare them away from swimming holes. He said swimming away from vegetation will reduce one’s chances of contracting the infection.
“If you swim at designated beach sites, usually the province does a good job of cleaning up those beaches and getting the vegetation off the beach area so people can enjoy the beach.”
The research team also is actively collecting snails for testing from lakes in the province, including Gull Lake, Sylvan Lake and Buffalo Lake. The group has funding for three summers to continue its work.