GSTM1 and anemia (phenotype): Late enrolments were significantly more likely to suffer from fever (OR: 2.17 CI95 [1.14, 4.08.38], p = 0.01), malaria (any density OR: 2.23 CI95 [1.13, 4.32], p = 0.011) and/or anaemia (Hb <7.5 g/dl, OR: 2.78 CI95 [1.40, 5.46], p = 0.001) than early enrolled children.