QUESTION

Three yrs old boy having fever every 20 days for past 5 times. Remains for 2-3 days. Can it be malaria?
Never got blood tested.

ANSWER

Recurrence of malaria every 20 days is not that common, but could be caused by two different events: (1) true relapse, whereby the boy is infected with either Plasmosium vivax or Plasmodium ovale, and the parasite is disappearing from his blood but re-emerging from dormant forms in the liver (called hypnozoites), or (2) what is known as recrudescence, whereby the parasite never disappears fully from the blood, but reduced enough to stop symptoms from being felt, then flares up again.

Both options can be treated, but require a blood test, to ensure that malaria is the correct diagnosis and also to distinguish between options 1 and 2 above, and different treatment will be required.

A blood test should be performed during a period where the boy is experiencing symptoms, as with both options above, if the infection is not “active” (i.e. few or no parasites are visible in the blood) a blood test may prove negative. Rapid diagnostic tests which look for antibodies might be a good choice in this instance, as they may detect even a non-active infection.