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Malaria diagnosis

WHO plates for diagosis of malaria

Plasmodium Falciparum
Key points
  • Fine ring forms in normal size red cells
  • Only species to show double chromatin dots and in which more than one trophozoite is found in a single red cell
  • Schizonts are rare in peripheral blood
  • Banana shaped gametocytes
  • Falciparum is the most dangerous form so it is important not to miss.

Plasmodium malariae
Key points
  • Tends to infect small, older red cells
  • Pigment is particularly prominent compared to other species
  • Only species to display band forms

Plasmodium Vivax
Key points 
  • Tends to infect larger red cells
  • Prominent Schuffners dots in the cytoplasm (also found in P. Ovale)

Plasmodium Ovale
Key points
  • Appearances are similar to vivax (larger cells, prominent cytoplasmic dots)
  • Key feature differentiating the trophozoites is the fibriated edge, which is easily missed unless you specifically look for it!