Leishmaniasis occurs in 88 countries around the world with an estimated annual incidence of about one million new cases, both visceral and cutaneous, which we will discuss later.

    Although most clinical syndromes are caused by zoonotic transmission of parasites from animals, mainly canines and rodents which act as reservoirs, humans are infected through phlebotomine sandfly vectors.

    Humans are the only known reservoir for visceral leishmaniasis in India and for transmission of leishmaniasis between injection drug users. The leishmania genus has many species and this is responsible for different types of diseases in different parts of the world as we will see later on.

    The life cycle of leishmania has two phases: a promastigote phase which has flagella and is introduced by the feeding sandfly.

   Promastigotes are taken up by the macrophages in the blood which are part of our....