Malaria is caused by a protozoan. It is widespread in tropical
Africa and south-east Asia. Malaria is caused by certain species of (Plasmodium malariae and Plasmodium falciparum). The parasites are transmitted to humans by the bites of infected female (Anopheles) mosquitoes.
The asexual cycle of the malarial parasite occurs in humans. When an infected mosquito bites a healthy person, it introduces parasites at the sporozoite stage into his body. These sporozoites migrate to the liver, multiply and develop into trophozoites which then invade the red blood cells. In these cells, they divide asexually forming numerous merozoites which when liberated, invade many other red blood cells. Some merozoites also develop into gametocytes. A mosquito picks up these gametocytes when it bites an infected person. The gametocytes develop in the mosquito's stomach where they reproduce sexually to form sporozoites. These migrate to its salivary glands, and are eventually transmitted to healthy humans through its bites.
Common Symptoms of malaria include;
*. Cyclic occurrence of chills (violent shaking).
*. Fever.
*. Profuse sweating.
These symptoms occur when the merozoites destroy the red blood cells, causing toxins to be released into the blood. Headache and nausea are the other common symptoms.
The secondary effects are mainly=>
*. Anaemia.
*. Jaundice.
*. And enlargement of the spleen.

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