Site author Richard Steane
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Developmental Cycle of the Causes of Malaria Exemplified by P. falciparum (GIEMSA stain)

  1. Sexual development (Gametogony) in the female Anopheles mosquito:

      1. Gametocytes taken up with the human blood,
      2. Gametes, blue = female cell (macrogamete)
        red = formation of the microgametes, so-called exflagellation.
      3. Fertilisation
      4. Zygote (so-called retort form)
      5. Ookinete
      6. Oocyst
      7. Sporocyst
      8. Mature sporocyst after it has burst open.
      9. Sporozoites in the cells of the salivary glands.
      1. Single sporozoite
      2. The biting Anopheles transmits sporozoites

      Pre-erythrocytic development in the cells of the liver:

    1. 3-7 Different stages of the so-called endothelial forms from the liver.

    2. Erythrocytic development (Schizogony):

      1. { Schizonts ("ring stages") of the species
      2. { which causes tropical malaria.
      3. Young schizont at a later stage of development: Erythrocyte with the so-called MAURER'S dots.
      4. Morula stage with about 20 merozoites.
      5. Merozoites which have become free infect more erythrocytes and partly become schizonts again and partly develop into gametocytes.
      6. Gametocytes (in this species, half-moon shaped) (for this, cf. I and II, d-e).

Typical stages in the Peripheral Blood

  1. Plasmodium vivax
  2. P. malariae
  1. Young ring-shaped schizont
  2. Multinucleate schizont
  3. Final stage of schizogony (the so-called Morula (I) or "daisy" (II))
  4. Male gametocytes
  5. Female gametocytes.
In P. vivax there are characteristic changes in the erythrocytes: they are enlarged and often show, when they are stained with Giemsa, SCHUFFNER'S dots!This is column 3

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