Swimmer's Itch
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What is Swimmer's Itch?
Swimmer's itch is a skin reaction to contact with the larvae of a parasitic fluke, which are found in contaminated freshwater. The larvae are called cercariae. They are almost invisible to the naked eye because of their size. If you swim in contaminated water, the cercariae may stick to your skin. When you get out of the water and your skin dries, the cercariae bite as they penetrate your skin. They die shortly after. How do people get Swimmer's Itch?
The cercariae that are found in freshwater come from infected waterfowl. The cycle begins when snails become infected by contaminated waterfowl feces. The cercariae are released from snails to swim in fresh water where they again infect waterfowl - or swimmers; cercariae can't tell the difference. Thus, humans are considered accidental hosts. |
What EFFECTS does this infection have on your HEALTH?
Swimmer's itch causes the following symptoms:
- Within a short period of time after swimming, small reddish pimples appear on the skin;
- These pimples can be found on every part of the skin that was in direct contact with water during swimming;
- A few hours later pimples swell into blisters that look like mosquito bites, and can reach the size of a dime;
- Intense itching can develop and last over 10 days. It usually resolves within a week or two;
- Some infected individuals may also develop a minor skin infection.
How can Swimmer's Itch be prevented?
Avoid, swimming in areas where there have been reports of cases of swimmer's itch. Reduce the amount of time you spend in the water to a few minutes. Towel dry vigorously when you get out of the water; your skin should not be allowed to air dry Inform other swimmers if you become infected. Do not feed waterfowl. |
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Do not scratch the rash to avoid getting a skin infection. To relieve the itch, apply a cream or lotion, such as calamine lotion. When in doubt, ask your pharmacist. If the itch persists more than a few days or you do not feel well, consult your doctor.
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Other things you should know...
Even though swimmer's itch causes a rash and itching, it is not considered a major health problem. It cannot be spread from person to person and there is no link between swimmer's itch and water pollution. |
Source: Developed by the Department of Health and Social Services of Quebec.
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The patient information leaflets are provided by Vigilance Santé Inc. This content is for information purposes only and does not in any manner whatsoever replace the opinion or advice of your health care professional. Always consult a health care professional before making a decision about your medication or treatment.