hypnozoite

biology

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Last updated

July 17, 2026

Quick Summary

The term "hypnozoite" refers to a dormant stage of certain malaria-causing parasites, specifically Plasmodium vivax and Plasmodium ovale. These parasites infect red blood cells and are transmitted by Anopheles mosquitoes.12

After a mosquito bite, immature forms called sporozoites enter the bloodstream and travel to the liver. There, they mature into schizonts, which then divide into thousands of merozoites. While most merozoites infect red blood cells, some P. vivax and P. ovale sporozoites can remain inactive in the liver for extended periods, forming the hypnozoite stage. These hypnozoites can later reactivate, leading to relapses of malaria even after the initial infection has seemingly cleared.1

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malaria
The course of the disease
…the liver in a “hypnozoite” stage for months or even years before emerging to attack red blood cells and cause a relapse of the disease.
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…the liver in a “hypnozoite” stage for months or even years before emerging to attack red blood cells and cause a relapse of the disease.
Read More