What is swimmer's itch and how can I avoid it?
Barb Liukkonen, Ext. Ed.-Shoreland Management
What is Swimmers' Itch?
Swimmer's itch is common around Minnesota's lakes in midsummer. Red, itchy welts appear on your skin within several hours of leaving the water. It may last a few days to several weeks, depending on your sensitivity.
How can I avoid Swimmers' Itch?
Reduce your chances of getting severe swimmers' itch by following these simple guidelines.
- Dry off as soon as you leave the water. Rub skin briskly to remove water drops before they evaporate. Be sure to dry underneath waistbands and around leg openings. Encourage children to dry off thoroughly each time they leave the water.
- Shower with soap and fresh water or change into dry clothes as soon as possible.
- Don't wade or play in shallow water. Swimming from a raft or pontoon minimizes your exposure.
- Don't feed geese and ducks near your beach. Waterfowl are an important adult host for the parasites.
Where does Swimmers' Itch come from?
Swimmer's itch comes from a microscopic parasite (Schisosome cercariae) that has a complex life cycle involving water birds or mammals, snails, and free-swimming stages. During one of its free-swimming stages, humans can be exposed to the parasites in lake water. When a swimmer leaves the water and water drops begin to evaporate, the tiny parasites burrow into the skin to try to survive. Where water is held near the skin (at waistbands and leg openings) the parasites have more time to burrow in.
People cannot become a host for the parasite, either through skin penetration or by swallowing lake water because the parasites are killed by the body's natural defense mechanisms.
Is there any treatment?
Some sunscreens and lotions may reduce the infections, although nothing is known to be completely effective. If you get swimmers' itch, lotions or ointments may relieve the itching. In severe cases, you may need to consult a physician.