Leishmaniasis is a major vector-borne parasitic disease affecting 12 million people worldwide. With a broad range of clinical manifestations, ranging from self-healing skin ulcers to disfiguring mucosal lesions to life-threatening infections of visceral organs (liver and spleen), the disease has become a serious human health issue, particularly in developing countries. Among all of its forms, visceral leishmaniasis (VL, also known as kala-azar), caused by the Leishmania donovani complex (i.e., L. donovani and L. infantum in Old World and L. chagasi in New World), is often fatal in the absence of treatment. Although humans are the principal hosts for L. donovani, canine species are the main reservoirs of L. infantum. Canine VL affects millions of dogs and is associated with outbreaks of human VL and hence has become a major public health issue. The lack of vaccines to prevent and/or treat these infections, as well as the emergence of drug resistant parasites, is serious impediments to control leishmaniasis. Therefore, developing new prophylactic and therapeutic strategies against this disease is urgently required. However, for this to occur, a better understanding of the complex immune mechanisms generated in response to infection and defining those involved in resistance to infection is required. In this special issue on “Immunity to visceral leishmaniasis”, several selected papers will discuss these issues.Peer reviewe
