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Leishmania donovani

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  Leishmania donovani: Life Cycle, Pathogenesis, Treatment Prevention and Diagnosis   Leishmania donovani: The Causative Agent of Kalaazar (Visceral Leishmaniasis) Lifecycle   Reservoir Hosts: Various mammals (e.g., dogs, foxes, rodents).   Vector: Female sandflies.    Require blood meals for egg maturation.    Ingest macrophages containing amastigotes when feeding on an infected host. Inside the Sandfly: 1. Amastigotes transform into promastigotes in the gut. 2. Promastigotes multiply and migrate to the pharynx and proboscis. 3. This process takes about 10 days. Transmission to Humans: 1. Sandfly bites human, injecting promastigotes. 2. Promastigotes are engulfed by macrophages. 3. Inside macrophages, promastigotes transform back into amastigotes. Within the Human Host: 1. Amastigotes evade destruction by preventing vacuolelysosome fusion. 2. Infect other macrophages and reticuloendothelial cells. Cycle Completion:   Another sandfly ingests

Leishmania donovani: Life Cycle, Pathogenesis, Treatment Prevention and Diagnosis

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    Leishmania donovani: The Causative Agent of Kalaazar (Visceral Leishmaniasis) Lifecycle Leishmania donovani's life cycle, relies on sandflies as vectors and various mammals, including dogs, foxes, and rodents, as reservoirs. Female sandflies, requiring blood meals for egg maturation, ingest macrophages containing amastigotes when feeding on an infected host Inside the sandfly, the amastigotes transform into promastigotes in the gut, multiply, and migrate to the pharynx and proboscis, ready to be transmitted during the next bite. This sandfly phase takes about 10 days. Upon biting a human, the sandfly injects promastigotes, which are engulfed by macrophages and transform back into amastigotes (Figure 1). Amastigotes evade destruction by preventing the fusion of the vacuole with lysosomes, leading to the infection of other macrophages and reticuloendothelial cells. The cycle completes when another sandfly ingests macrophages containing amastigotes.