A lot has already been talked and written about the significance of the leucocyte and platelet counts in the diagnosis of common fevers.

Can the level of haemoglobin help in the diagnosis? Yes. In a middle or upper class society, and that too more often in a male patient, if the level of haemoglobin is low, the diagnosis is in favour of malaria, especially the falciparum type.

It is also worth noting that often, bad falciparum malaria can mimic a bad case of dengue fever. In the later, levels of haemoglobin are higher than normal due to haemoglobin concentration. This finding may be helpful in differentiating the above two illnesses.