According to the Iowa Department of Natural Resources (DNR), swimmers who frequent Iowa’s natural lakes should be wary of ‘swimmer’s itch’.
The condition is caused by parasitic flatworms that penetrate human skin before immediately dying; this causes itchy, red welts to appear that may persist for up to a week.
So far, cases have been reported from Black Hawk Lake and Crystal Lake.
Swimmer’s itch can be prevented by avoiding areas rife with aquatic plants, reducing time spent in the water, and drying off quickly after swimming. The condition does not generally require medical attention, and can be treated with calamine lotion and an antihistamine.
For more information, read the DNR report here.