Cercarial dermatitis, also known as swimmer's itch, is caused by certain parasites found in freshwater and some coastal saltwater bodies of water. When these larvae accidentally choose a human -- instead of waterfowl -- as a host, they bore into skin and die there, causing irritation and itching that usually goes away within a few days. The condition isn't harmful, and over-the-counter or prescription medications can relieve intense itching, if necessary. Take precautions to avoid swimmer's itch when swimming in natural bodies of water.
Step 1
Stay away from bodies of water that are known to transmit swimmer's itch. Look for posted warning signs before entering the water.
Step 2
Swim away from the shore, if possible. Shallow water is more likely to contain the parasites that cause swimmer's itch.
Step 3
Avoid water populated by snails, which serve as the intermediate host for the larvae that cause swimmer's itch.
Step 4
Shower as soon as possible after swimming and rub your skin with a towel to dry thoroughly.
Step 5
Wash your swimsuit after every swim. Have more than one suit available so you have one to wear while the other is in the wash.
Step 6
Don't feed waterfowl while you're swimming, which encourages them to stay in the area.
Tips and Warnings
- If you own the pond or lake you're swimming in, trim the vegetation around the lake and clear the water of as much vegetation as possible to keep the snail population down. Other methods of control, such as using chemicals to kill the snails or treating infected birds with medication, can be costly and require professional help.
