Leishmania are protozoan parasites that cause several human diseases called leishmaniases, which can display very different clinical aspects (Peters and Killick-Kendrick, 1987b). The life cycle of Leishmania involves two kinds of hosts: dipteran insects (sandflies) and several mammals, in which they adopt a motile, flagellated, promastigote form and a non-motile, amastigote form with a very sho...