Malaria parasites spread by successful infecting two types of hosts, female anopheles mosquitoes and humans. At the same time she takes a blood meal to nourish her eggs, the female anopheles mosquito injects sporozoites into the blood stream of malaria’s next victim.
The sporozoites are rigidly taken up by the liver cells.
In all species of plasmodium these parasites develop to form schrizonts (the multinucleate stage of the cell during a sexual reproduction) from which several thousand merozoites develop.
In plasmodium vivax and plasmodium ovale only a proportion of the liver-stage parasites (known as hypnozoites) remain dormant in the hepatocytes. In this stage the parasite can remain dormant for months or several years; these two species of parasite can therefore initiate a cycle of a sexual reproduction causing clinical symptoms in the absence of a new mosquito bite.
When the liver cell ruptures, the merozoites are released into the blood stream where they rapidly invade the red blood cells, these blood-stage parasite replicate a sexually-rapidly attaining a high parasite burden and destroying to the clinical symptoms of malaria.
The trigger is as yet unknown, but a small percentage of merozoites differentiate into male and female gametocyte, which are taken up by the mosquitos in her blood meal. It is these gametocytes that cause the cycle of transmission to continue back to the mosquito male and female gametocycle fuse within the mosquito forming diploid zygotes, which in turn become ookinete.
These ookiness migrate to the midgut of the insect, pass through the gut wall and form the oocyte.
Meiotic division of the oocytsts occur and sporozoites are formed which then migrate to the salivary glands of the female Anopheles mosquito ready to continue the cycle of transmission back to man.
Therefore, peoples should have to take a proper care to protect their health by using acceptable insecticides or mosquito net, and clean their environment to be very neat, health is wealth.
Bailawi Umar Abdullahi,
Mass Communication Department,
University of Maiduguri,
Maiduguri (08036692416)
