The findings in this study are: (1) Plasma AOPP is a valuable oxidative stress biomarker of anaemia and clinical malaria infection in children two years old living in a malaria endemic area; (2) Preceding levels of AOPP predict to some extent the development of anaemia in children two years old; and (3) Variants in GCLC, GSR and HMOX1 genes are associated with the host oxidative stress status, which was evidenced by their associations with AOPP levels. This evidence concerns the gene HMOX1 and anemia (phenotype).