Schistosomes causing cercarial dermatitis: a mini-review of current trends in systematics and of host specificity and pathogenicity.

The human infection known under the names cercarial dermatitis or swimmers' itch is generally associated with swimming in lakes all over the world, however, a number of outbreaks of cercarial dermatitis developing in salt or brackish waters are also reported. The disease presents as allergic reaction which is able to trap and eliminate the parasites in the skin. However, the infection can be linked to more than skin symptoms under certain circumstances. Recent studies on bird schistosomes have shown that during primary infections of noncompatible hosts (mice) the parasites may migrate through visceral and nervous tissues of mammals. Up to date, cercarial dermatitis has been mostly associated with the cercariae of bird schistosomes of the genus Trichobilharzia. Recent findings of new genera and species indicate, however, broader spectrum of causative agents of the disease with different life cycles, host specificity and pathogenicity.