Life Cycle

This is the life cycle of Plasmodium falciparum, the species that is most responsible for malaria in the world. It is a complex life cycle that alternates between asexual and sexual reproduction. It also alternate between human and mosquito hosts.

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When I am transmitted from the mosquito to a human, I am in the sporozoite form. A female infected mosquito will inject the sporozoites with her saliva when she has a blood meal. I am transferred directly into the circulatory system which delivers me straight to my target: the liver. Here, I enter a host cell in the liver and my nucleus divides many times, producing new Plasmodium cells in the form of merozoites. The liver cells burst and the merozoites enter the bloodstream. Once in the bloodstream, merozoites infect red blood cells where they reproduce asexually and burst out of the cell. The new merozoites infects other red blood cells. This cycle repeats itself over and over again. Every time the release of new merozoites happens, bouts of fever occur, which is what malaria is. Some of the merozoites will develop into gametocytes, which do not harm the host. However, the mosquito takes the gametocytes during a blood meal and they develop into gametes. A male and female gamete come together to form the zygote, which matures into the ookinete. Sexual reproduction occurs in the mosquito. The ookinete moves to the wall of the mosquito's gut, and develops into an oocyst. The oocyst ruptures and releases sporozoites, which migrates to the salivary glands. Through the mosquito's saliva, the sporozoites infect the next human and the cycle continues.