Skip to main content

Thurston County, Washington

The content on the Thurston County website is currently provided in English. We are providing the “Translation” for approximately 10 languages. The goal of the translation is to provide visitors with limited English proficiency to access information on the website in other languages. The translations do not translate all types of documents, and it may not give you an exact translation all the time. The translations are made through an automated process, which may not result in accurate or precise translations, particularly of technical and legal terminology.
swimmer in pool itching inside of forearm due to swimmer's itch

OLYMPIA – Thurston County Public Health and Social Services advises members of the community the parasite causing swimmer’s itch appears to be present in Long and Clear Lakes. Multiple reports were received from individuals who swam at Long Lake and appear to have swimmer’s itch. Two individuals who live on Clear Lake reported they have swimmer’s itch. Additionally, swimmers at any freshwater lake need to be aware this parasite may be present and there are ways to avoid being infected by it.

Swimmer’s itch, also called cercarial dermatitis, appears as a skin rash caused by an allergic reaction to certain microscopic parasites that infect some birds and mammals. These parasites are released from infected snails into fresh and saltwater (such as lakes, ponds, and oceans). If the parasite comes into contact with a swimmer, it burrows into the skin causing an allergic reaction and rash.

Swimmer’s itch is found throughout the world and is more frequent during summer months. The parasite does not have long-term effects for those who encounter it. Symptoms may include tingling, burning, or itching of the skin.

Follow these steps to reduce your likelihood of getting swimmer’s itch:

  • Choose not to swim in areas where swimmer’s itch is a known problem or where signs have been posted warning of unsafe water.
  • Choose not to swim near or wade in marshy areas where snails are commonly found.
  • Towel dry or shower immediately after leaving the water.
  • Apply water-proof sunscreen to your body before entering the water to both protect you from the sun and reduce the ability of the parasite to attach to the skin.
  • Do not attract birds (e.g., by feeding them) to areas where people are swimming.  


Public Health and Social Services
Press Release

Questions and inquiries regarding News Release content should be directed to the Thurston County Public Information Officer:  

Meghan Porter

Anna Rhoads