**3.1 Mode of transmission**

The disease is mainly transmitted by the bite of a 2–3 mm in size female "*Phlebotomus* sand fly" in Old World leishmaniasis and *Lutzomyia* in the New World disease. There are approximately 20 pathogenic *Leishmania* species and up to 500 known phlebotomine sand fly species identified as vectors of disease [17, 18]. The disease is mostly zoonotic with humans being incidental hosts infected by sand fly bite.
