ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferencesView all Images (16)
Cercarial dermatitis in Child
Other Resources UpToDate PubMed

Cercarial dermatitis in Child

Print Images (16)
Contributors: Vivian Wong MD, PhD, Edith Lederman MD, Susan Burgin MD
Other Resources UpToDate PubMed


Swimmer's itch, also known as cercarial dermatitis or clam digger's itch, is an allergic dermatitis to the abortive penetration into the skin by cercariae of mammalian and avian schistosomes (Trichobilharzia and Bilharziella) after exposure to water containing the intermediate snail hosts. The schistosomes may cause an immunological reaction in the form of cercarial dermatitis in individuals who have been sensitized to the schistosomes.

There is a worldwide distribution, with human schistosomes more common in tropical climates (most commonly Schistosoma mansoni and Schistosoma hematobium).

Swimmer's itch typically presents as a pruritic rash on skin 24 hours after exposure to water containing cercaria in endemic areas. The cercariae enter the stratum corneum and die within hours. The rash is associated with moderate pruritus that is self-limiting but may persist for several weeks. Some patients may develop a delayed rash several days after initial exposure.

Cercarial dermatitis may become more severe with repeated exposure. Patients may develop edema, papulovesicles, and intense pruritus.

Rare presentations have been reported on the upper extremities after cleaning fish tanks.

There are no age or sex predilections.


B65.3 – Cercarial dermatitis

187115002 – Cutaneous schistosomiasis

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Best Tests

Subscription Required

Management Pearls

Subscription Required


Subscription Required


Subscription Required

Last Reviewed: 12/18/2018
Last Updated: 01/10/2020
Copyright © 2020 VisualDx®. All rights reserved.
Cercarial dermatitis in Child
Print 16 Images Filter Images
View all Images (16)
(with subscription)
Cercarial dermatitis : Primarily truncal, Symmetric extremities, Fresh water exposure, Saltwater exposure
Clinical image of Cercarial dermatitis
Copyright © 2020 VisualDx®. All rights reserved.