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Calvin News

Studying Swimmers' Itch

Thu, May 24, 2001
N/A

Calvin College biology professor Curt Blankespoor and junior biology major Lindsey Walters (left) of Grandville will work this summer on something that Blankespoor calls "a problem from Maine to Montana."

The two will join Hope College biology professor Harvey Blankespoor (Curt's father) and a Hope student to study "swimmers' itch." Hudsonville High School biology teacher Ron Reimink also will work on the project.

Their laboratories will be Lake Mitchell and Lake Cadillac in Cadillac, Michigan. Their subjects will be swimmers willing to swim in the lakes and fill out logs that detail their swimming and their itching.

In fact, Curt Blankespoor will head to Cadillac this Saturday (May 26) to attend a Lake Mitchell Association meeting and recruit volunteers for the diaries.

"There's a lot of anecdotal evidence surrounding both the prevelance of swimmers' itch and the effectiveness of the various control options," says Blankespoor, "but not a lot of scientific assessment. This summer we have the chance to study two lakes where traditional control methods have not been used for the past two years. It's a very nice opportunity and it will be a great experience for the two students."

The problem in Michigan is usually caused by a parasite that originates with the waste of the merganser duck. But there are close to 20 different species of parasite that can cause the affliction, each using its own vertebrate and snail host. So finding out which parasite causes the itch will be the team's first order of business.

"Right now," says Blankespoor, "is when swimmers' itch is on people's minds because the birds are brooding."

After the particular parasite that causes swimmers' itch in Lakes Cadillac and Mitchell is determined the second challenge will be to decide if the problem is significant enough to warrant treatment.

In the past the lakes have been treated with copper sulfate which kills the snails which carry the parasite which causes the itch. That will not happent his summer. Instead the Calvin/Hope team will receive $14,000 from the Department of Public Works to conduct the study, money the department would have paid to treat the lakes this summer.