Abstract: AIM: To make an epidemiological survey of schistosome cercarial dermatitis among
the residents living along the banks of the Huaihe River. METHODS: Making inquiries about signs
and symptoms of schistosome cercarial dermatitis, and physical examinations of manifestation in
the residents (fishermen and peasants). Cercariae shed from the Radix auricularia collected in
the field were used to infect ducklings. The eggs and miracidia separated from the feces of the
full grown ducks bred by fishermen were used to infect Radix auricularia. RESULTS: Schistosome dermatitis locally known as“duck itch”(meaning duck-feces-dermatitis) was discovered among the residents living along the Huaihe River bank. The main signs and symptoms of the dermatitis included diffuse erythema or red papular eruption with areorae、urticae、urticant itch or titillation around the affected areas ( including thoracic part, abdomen and lower limbs etc). The cercariae with eye spot were found from Radix auricularia collected from Huaihe riverside and were identified to be the species of Trichobilharzia can both hatch miracidium , which laboratory-reared Radix auricularia were infected with miracidia hatched from the two types of eggs, rhomboid eggs and crescent eggs, found in the feces of full grown ducks bred by fishermen and shed the same cereariae with eye spot. Besides, adult worms of Trichobiharzia were obtained by disecting both experimentally infected duckilings bred in the laboratory and naturally infected ducks bred in the Huaihe riverside area. The above-mentioned eggs, miracidia, cercariae and adult worms were all identified to belong to the life-phase of Trichobilharzia. CONCLUSION: The epidemic disease known as schistosoma cercarial dermatitis harmful to the health of the residents living along the banks of Huaihe River is caused by the cercariae of Trichobilharzia.

Key words: Huaihe river, Trichobilharzia, schistosome cercarial dermatitis