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By different serological methods (cercarial fluorescent antibody test, cercarial Hullen reaction, circumoval precipitin test) antibodies against cercariae could be demonstrated in the serum of the patient 14 days post-infection. A diagnosis can also be made through consideration of the patient’s history of exposure as well as by stimulating cercariae secretions in captured snails from outbreak areas. In addition, the symptoms of cercarial dermatitis are highly distinctive.