BALTIMORE (WJZ) — About 80 ducklings have been found dead in the Lincoln Memorial Reflecting Pool since May 20 due to parasites, according to the National Park Service.

The pool will be drained, cleaned and refilled over the course of the week beginning on June 11 because chemical treatments are not sufficient to reduce the parasite population, which comes from snails.

NPS says humans who come in contact with the parasite could develop “swimmer’s itch” (cercarial dermatitis), an allergic reaction in the form of a skin rash. It is not contagious, rarely requires medical treatment, and risk of contracting it at the reflecting pool is very low since it would require sustained contact with the water.

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