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About the Cover
Cover:
Life cycle of the malaria parasite Plasmodium. Merozoites are released from the human liver cell (top) and penetrate red blood cells, where they multiply, forming a schizont. Some merozoites that are released from the schizont reinvade red cells and multiply again, whereas others develop into female macrogametocytes or male microgametocytes. The gametocytes are taken into the mosquito with a blood meal. Macrogametocytes shed the red cell membrane, becoming free macrogametes within the mosquito midgut lumen. Each microgametocyte produces eight microgametes. The microgametes fertilize the macrogametes, which develop into ookinetes that penetrate the midgut wall of the mosquito and develop into oocysts. The oocysts emerge from the opposite side of the midgut wall, where they rupture, liberating sporozoites into the mosquito's haemolymph (blood). The sporozoites travel in the haemolymph to the mosquito's salivary gland and are injected into the human's blood along with the mosquito's saliva. The sporozoites penetrate the human liver cells, where they multiply, producing a large number of merozoites ready to continue the deadly life cycle. Image of child reproduced with permission from WHO/TDR/S. Lindsay.
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