Who discovered Kala-azar fever?

U.N. Brahmachari identified Leishmania donovani as the causative agent of Kala-azar (visceral leishmaniasis) in the early 20th century and developed urea stibamine, an effective treatment. This tropical disease, transmitted by sandflies, was devastating in India. His diagnostic methods and therapeutic advances saved countless lives. Brahmachari's work established the medical understanding of this parasitic disease and provided treatment where none existed before.