Definition
By Mayo Clinic staffSwimmer's itch is an itchy rash caused by certain parasites that normally live in freshwater snails and sometimes on waterfowl.
On warm, sunny days, these parasites can be released into mainly fresh water or occasionally salt water. During your swim, the parasites might burrow into your skin, where they cause the swimmer's itch rash. But humans aren't suitable hosts for them, so the parasites soon die while still in your skin.
Although uncomfortable, swimmer's itch is usually short-lived. The rash of swimmer's itch, also called cercarial dermatitis, typically clears up on its own within a few days. In the meantime, you can control itching with over-the-counter or prescription medications.
- Wilson ME, et al. Helminthic infections. In: Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 7th ed. New York, N.Y.: The McGraw-Hill Companies; 2008. http://www.accessmedicine.com/content.aspx?aID=3000222&searchStr=schistosomiasis%2c+cutaneous#3000222. Accessed Nov. 10, 2010.
- Wolff K, et al. Arthropod bites, stings and cutaneous infections. In: Wolff K, et al. Fitzpatrick's Color Atlas and Synopsis of Clinical Dermatology. 6th ed. New York, N.Y.: The McGraw-Hill Companies; 2009. http://www.accessmedicine.com/content.aspx?aID=5197009&searchStr=schistosomiasis%2c+cutaneous#5197009. Accessed Nov. 10, 2010.
- Swimmer's itch (cercarial dermatitis). Centers for Disease Control and Prevention. http://www.cdc.gov/ncidod/dpd/parasites/cercarialdermatitis/factsht_cercarialdermatitis.htm. Accessed Nov. 10, 2010.
- Swimmer's itch. American Osteopathic College of Dermatology. http://www.aocd.org/skin/dermatologic_diseases/swimmers_itch.html. Accessed Nov. 10, 2010.


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