The penetration of mammalian skin by cercariae of Trichobilharzia sp. (Trematoda: Schistosomatidae) from South Africa.

The ability of the cercariae of Trichobilharzia sp., the commonest avian schistosome in South Africa, to cause dermatitis in man is confirmed, and their progress through and resultant histopathology in rodent skin are documented. These cercariae reach the subcutaneous tissue within one hour after exposure, and some migrate to the lungs. Between 46 and 97 h later, those stranded in the skin have died, while those in the epidermis are extruded by 97 h. There were haematological changes in the peripheral blood and a rapid rise and fall in the mitotic rate of the basal epithelium of the epidermis.