Malaria_Cycle of disease

http://www.emro.who.int/rbm/Images/MalariaLifeCycle-1.gif

As the mosquitoes feed on human blood, it also injects saliva containing an anti coagulant, which prevents the blood from clotting in its proboscis (feeding tube). If this saliva contains plasmodium sporozoites, the human host becomes infected. These sporozoites (haploid parasite formed in the mosquito) then invade the human liver cells and begin to asexually reproduce. After a period of two – four weeks, the merozoites (daughter cell) from the parasites burst with toxin and begin to invade red blood cells of the human. The merozoites then developed into gametocytes, which are then sucked up by another female anopheles mosquito. Within this new mosquito, the gametocytes (sexual stage of the malarial parasite) develop into gametes, which become fertile and developed into zygotes (fertilised egg cell). Meiosis then occurs forming sporozoites, which migrate to the salivary gland and can then be injected into a human host along with the saliva.