 This proposal aims to evaluate the safety and efficacy of artemisinin-based anti-malaria combination drugs ACTsfor treatment of children aged 1-10 years in different locations in Cameroon. Randomized clinical trials will provide local data on the safety of the test drugs, and on putative marker mutations of the development of resistance to ACT. The study will involve three centres, namely, Banso Guinea-Savannah region, LimbeLittoral Forest, and GarouaSahel-Savannah. The trial will compare the efficacy and safety of AmodiaquineAQ-ArtesunateArt with CoartemArtemether-Lumefantrine. Drug efficacy will be determined using a WHO standardised 28 day protocol. Safety will be monitored through clinical examination, and biochemical and haematological indices. Molecular markers of artemisinin resistance will be investigated by molecular sequencing and comparison of parasite profiles of the PfATP6 gene in drug failure cases, . Recrudescences or re-infections will be assessed by analysis of the msp1 and msp2 genes. The impact of these combinations on generation of gametocytes will be determined from gametocyte carriage rates measured by microscopy. 