Avoid swimming in areas where swimmer’s itch is known to be a problem or near the shoreline or in marshy areas, where snails are more likely to live. After swimming, be sure to rinse off with clean water and dry yourself with a towel. Launder your swimsuits often. Avoid feeding geese and ducks along docks and the water’s edge. There is no evidence that waterproof sunscreens are effective at preventing swimmer’s itch.