Leishmania, the causative agent of kala-azar, multiplies asexually by

Leishmania is a genus of protozoan parasites responsible for visceral leishmaniasis, commonly known as kala-azar [t2][t9]. These single-celled organisms multiply asexually through longitudinal binary fission [t6][t8]. In this process, the parent cell divides into two identical daughter cells [c4]. The life cycle of Leishmania involves two primary stages: the extracellular promastigote form found in the sandfly vector and the intracellular amastigote form found within the host's macrophages [t1][t5]. In both stages, the parasite replicates asexually to increase its population [t7][t10]. While other protozoa like Plasmodium (the malarial parasite) undergo multiple fission to produce many daughter cells simultaneously, Leishmania specifically utilizes binary fission as its primary mode of asexual reproduction [c1][t8]. This method ensures the rapid spread of the parasite within the host's reticuloendothelial system, leading to the clinical symptoms of the disease.

Sources

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