Photo courtesy of dermatology image atlas

Mild itching and macular eruptions appear hours after leaving the water. Intense itching and distinct papules may be present ten to fifteen hours later. The itching generally persists for a week or longer. Papules occur only on skin areas where larvae penetrated during water contact and do not spread. Cases can range from several itchy spots to spots covering the whole body, depending on exposure to water and cercariae. The skin usually heals within two weeks, unless papules are infected from scratching or water contamination. Swimmer's itch is sometimes confused with insect bites and allergic reactions. Preventive actions have been proposed, such as applying oils, lotions, or insect repellent before water exposure, or wearing wet suits or waders. However, applying a layer of grease or oil on the skin may actually be counteractive as it encourages the attachment of cercariae that normally penetrate the oily skins of water fowls. After exposure, people may rub briskly with a towel or bath brush or rub alcohol on the skin. No scientific study of effectiveness of pre- or postexposure prophylaxis has been done to date. Responses increase in severity with each subsequent exposure to the parasite.

Increased severity of repeated infection

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