Bird schistosomes: do they die in mammalian skin?

The cercariae of bird schistosomes, released from the intermediate water snail host, actively penetrate the skin of both birds and mammals. Whereas in birds the infection leads to worm maturation and egg production, in the mammalian hosts skin invasion is accompanied by cercarial dermatitis (swimmer's itch, clam-digger's disease) and the fate of the parasites is not clear. Here, we review bird schistosomes as causative agents of cercarial dermatitis, underline adaptations of bird schistosomes to their life in vertebrate hosts, and discuss potential risks caused by the parasites migrating in humans.