This clinical trial evaluates the advantage of prolonging the therapeutic life span of Artemether-lumefantrine from 3 days to 6 days, and addition of single low dose of Primaquine 0.25mg/kg. The study will have two arms, one that will receive standard treatment of uncomplicated malaria with Artemether-lumefantrine, and the other arm will receive the prolonged dose of 6 days together with single low dose primaquine. This approach is expected to provide strategies for malaria control in an era of imminent Plasmodium falciparum resistance.