Inclusion Criteria: Neonates: 1) Preterm born before 37 weeks of pregnancy admitted for inpatient care at HGT or Neonates aged between 0 - 28 days admitted for inpatient care at HGT 2) Admission weight more than 2000 grams 3) Parental informed consent obtained and signed for infant participation Criteria for Mothers: - Consenting mother of an enrolled infant Exclusion Criteria: Neonates: 1) Outpatient infant 2) Infant weighing less than 2000g 3) Infants presenting the following symptoms of critical condition: bradycardy, gasp, severely altered general condition 4) Presence of severe anemia 5) Infants who are judged by the study physicians to be unfit for enrollment for any reason 6) Informed consent denied Criteria for Mothers: 1) Mothers with severe malaria (2) 2) Mothers with an acute severe disease 3) Mothers who are judged by the study physician to be unfit for enrollment for any reason 4) Informed consent denied