Cohort 1 (home visits):  The criteria for inclusion of children in the main cohort are:  6-6.9 months of age Child singleton The mother must live in the study area from the time of inclusion. The consent of the mother or guardian  The exclusion criteria are :  Congenital malformations that make anthropometric measurements impossible. Mother intends to leave the study area by December 2021.  Cohort 2 (health registers-based):  The criteria for inclusion in the treatment cohort are :  The child is included in a national treatment program. The child is between 6 and 23 months of age at inclusion Child lives in one of the 100 villages in the study area  Cohort 3 (home visits):  The inclusion criteria for the relapse study are:  Child has been successfully treated for wasting (moderate or severe) and has been discharged from the national treatment program within the last 30 days. The child is between 6 and 23 months of age at inclusion. The child is singleton. The mother must live in the study area from the time of inclusion. The consent of the mother or guardian  The exclusion criteria are :  Congenital malformations that make anthropometric measurements impossible. Mother intends to leave the study area by December 2021.