Nanomedicines for Therapy of Visceral Leishmaniasis

Visceral leishmaniasis (VL) or kala-azar is a vector borne infectious disease caused by the protozoan parasites of the genus Leishmania. VL is endemic in more than 85 countries with an estimated 0.2-0.5 million people at risk, causing high morbidity and mortality across the globe. In the absence of effective vaccines, treatment solely relies on chemotherapy and can be 100% fatal within two years, if left untreated. However, the present chemotherapeutics is limited by toxicity, non-compliance, location of parasites within the lysosomal vacuoles of macrophages, impairing the accession of many potential antileishmanial drugs, prolonged and cumbersome regimen that is unaffordable by rural population with alarming increase in unresponsiveness, complications of post kala-azar dermal leishmaniasis (PKDL) and HIV co-infections. Nanotechnology offers promising approach in the treatment of VL as it reduces toxicity, improves the therapeutic index of drugs, and can selectively deliver the antileishmanial cargos to the intracellular pathogens. In addition, nanoparticles can interact with the host immune system, modulating the immune response in a way that may favor the elimination of the Leishmania parasites. In this review, we give an overview of the strategies and delivery systems employed for the antileishmanial drugs towards the riddance of deadly VL.