Contributor: John Winkler, MD

Educational Pearls:

• Swimmers itch is due to a flatworm parasitic infection that causes an itchy rash after the worm burrows into the skin
• The flatworm is passed between bird and snail hosts
• The itch is due to the death of the parasite under the skin which leads to an extremely itchy reaction.
• The rash can be difficult to identify, often erythematous and macular but can develop papules and vesicles eventually scaling
• The treatment is diphenhydramine for milder cases and steroids for more severe cases

References

Kolářová L, Horák P, Skírnisson K, Marečková H, Doenhoff M. Cercarial dermatitis, a neglected allergic disease. Clin Rev Allergy Immunol. 2013 Aug;45(1):63-74. doi: 10.1007/s12016-012-8334-y. PMID: 22915284

Summarized by Jackson Roos, MS4 | Edited by Erik Verzemnieks, MD