For this study, we propose to use the standard dose of SP + AS to clear asexual parasites, followed by a single dose of PQ to clear remaining gametocytes. Pregnant women and children under 1 years of age will be excluded from PQ treatment. Prior to the proposed study, a small scale clinical study was conducted in symptomatic children in Korogwe to determine the safety and gametocytocidal effect of SP + AS and SP + AS followed by PQ (NIMR/HQ/R.8a Vol. XIII/446; http://www.controlled-trials.com/ISRCTN61534963). We did do screen for G6PD deficiency prior to treatment in this pilot study and did not observe any side effects or clinical indication of anaemia in children treated with PQ.