GSTM1 and anemia (phenotype): The majority of children fulfilled one or more criteria of the WHO definition of severe malaria [23, 24], which include severe anaemia (haematocrit of <15 % or Hb <5 g/dL with a parasitaemia of >10,000/μL), hyperlactataemia (≥5 mmol/L), hyperparasitaemia (>250,000 parasites/μL), hypoglycaemia (whole blood or plasma glucose ≤2.2 mmol/L), and haemoglobinuria (urine that is dark red or black, with a dipstick that is positive for Hb/myoglobin).