Swimmer's Itch Warning Signs

Cercarial dermatitis, known as swimmer's itch, is caused by parasites that live in both birds and freshwater snails. The larvae from the parasites hatch and continue to develop in freshwater snails. They then leave the snails and seek a host on which they can complete their development, such as a bird or freshwater mammal. If the larvae come into contact with human skin, they will burrow into the skin and cause an itchy rash known as swimmer's itch.

Rash

• The most obvious sign of swimmer's itch is the development of a raised, red rash on the skin. The rash will develop where skin was exposed to fresh water. The rash may look like small pimples, but can develop into larger, blister-like sores. The rash will also itch. Humans are not suitable hosts for the larvae, and they will die within several days to a week. It is not contagious, and therefore cannot be passed from human to human. Rashes or sores that develop pus should be examined by a doctor.

Itching

• To treat the itching associated with swimmer's itch, use a corticosteriod cream. Coat the infected area with a baking soda paste or use an anti-itch lotion such as Calamine. Minimizing the itching will prevent the risk of secondary bacterial infections. The itch will typically dissipate within several days to a week when the larvae die. Infestation of these parasites may cause itching without the development of a rash.

Prevention

• The best prevention for swimmer's itch is to avoid ponds, lakes and other bodies of water where conditions are ideal for the parasite and its larvae to thrive. Be on the look out for exceptionally warm water where water fowl are abundant. Do not swim in bodies of water where you observe an abundance of snails. To minimize the risk of developing swimmer's itch, towel dry or shower immediately after swimming. Swimmer's itch can develop within minutes of swimming, or may take up to 48 hours.