Cutaneous leishmaniasis. View of a cutaneous leishmaniasis scar on the face of a girl. This tropical disease is caused by Leishmania sp., a parasitic protozoan, which is transmitted by bites from infected sand-flies. This is the less serious form of the disease, where a persistent ulcer develops around the sand-fly bite. While the ulcer eventually heals, scars (as here) are common. Drug treatment is effective. Photographed in Iran.