Towards the elimination of Plasmodium vivax malaria: Implementing the radical cure

Abstract

Efforts to control Plasmodium vivax malaria have been less successful than for PlasmodiumAU falciparum : PerCSE , resulting ; iftwodifferentspeciessharethesamegenus in higher prevalence of P. vivax malaria ; thegenusofthesecondspeciesshoulds in most coendemic regions. One of the key differences between the 2 species is the ability of P. vivax to form hypnozoites causing relapses which facilitate transmission. Preventing P. vivax relapses is key for the elimination of P. vivax malaria. • The widescale use of the radical cure to clear hypnozoites has been underutilized in most endemic countries. Two breakthroughs have increased the likelihood that the radical cure will be rolled out in P. vivax endemic regions: To clear hypnozoites, primaquine can be administered in short, high-dose regimens or a single dose of the recently licensed tafenoquine is administered. Novel technologies allow measurement of glucose-6-phosphate dehydrogenase (G6PD) activity at the point of care. Identifying patients with low G6PD activity, not eligible for these novel regimens, is a precondition for their safe administration. • Novel approaches to P. vivax elimination such as mass drug administrations of antimalarial drugs including 8-aminoquinolines require considerable resources and carry safety risks. • A safe and protective P. vivax vaccine would be an asset in the elimination of P. vivax malaria but is unlikely to be available in the near future. • Case management that includes a radical cure is currently the most promising approach to P. vivax elimination. New regimens for radical cure and the possibility to minimise the risk of haemolysis through novel G6PD tests bring up operational challenges, but if deployed wisely could have sufficient impact to eliminate if not eradicate P. vivax malaria.