Leishmaniasis: Current Trends in Microbiology and Pharmacology

Leishmaniasis is a neglected tropical disease infecting the world's poorest populations in over 90 countries throughout Asia, Africa, the Middle East, and Central and South America. Leishmania is transmitted to humans through the bite of infected female phlebotomine sandflies. Leishmaniasis is caused by various species of the Leishmania parasite, which can be broadly classified into Old World and New World species. The transmission and vector biology of leishmaniasis is important in the epidemiology and control of the disease. The distribution of leishmaniasis is closely linked to environmental factors, including climate, vegetation, and the presence of suitable vector species. In the Old World, Leishmania donovani and Leishmania infantum are responsible for visceral leishmaniasis (VL), while Leishmania tropica and Leishmania major cause cutaneous leishmaniasis (CL). In the New World, the Leishmania braziliensis complex is associated with CL and mucocutaneous leishmaniasis. The clinical diagnosis of leishmaniasis is a complex process that involves the evaluation of various clinical signs and symptoms, epidemiological factors, and laboratory tests. Pentavalent antimonials like sodium stibogluconate and meglumine antimoniate have been the primary treatment for leishmaniasis for many years. Amphotericin B, available in different formulations, is often used as a second-line treatment for severe or drug-resistant cases. Miltefosine, the only oral drug approved for leishmaniasis treatment, is effective against various Leishmania species but its use is limited due to the development of resistance. Target-based drug discovery approaches involving designing compounds that specifically target essential proteins or metabolic pathways within the Leishmania parasite have been identified. These approaches aim to enhance drug efficacy, reduce toxicity, and overcome drug resistance.