What causes Malaria?

Overview

Malaria is spread when a human is bitten by a mosquito that has previously bitten an infected person and uptaken the malaria causing parasite; the parasite is now passed from person to person via the mosquito.The mosquito digests the parasite from the infected blood and in a week can be passed on to another human.

The Cycle

The parasite enters the humans blood stream where it circulates to the liver and infects the hepatoctyes within 30 minutes of its entry into the body. Here the parasite reproduces and grows into merozoites. At this time however the human does not know that he/she has the parasite in their system as there are no visible signs or symptoms that the parasite is there.

The parasite has been known in some cases to stay in the persons liver for years. Once it has left the liver in the red blood cells it contimues to grown until the cell bursts causing the merozoites to be released and able to attack other blood cells. Then, the merozoites infect red blood cells, where they develop into ring forms, then trophozoites (a feeding stage), then schizonts (a reproduction stage), then back into merozoites. Sexual forms called gametocytes are also formed and it these that are uptaken by mosquitos again when this person is bitten.

The cycle is repeated when a mosquito then bites are person at this stage, uptaking the parasite and meaning it is abe to infect someone new.

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