Interventions for the control of diarrhoeal diseases among young children: Promotion of breast-feeding

The literature of the relative risks of diarrhoea morbidity to infants on different feeding modes suffers from several methodological problems. Thirty-five studies from 14 countries were reviewed; 83% of studies found that exclusive breast-feeding was protective compared to partial breast-feeding, 88% that exclusive breast-feeding was protective compared to no breast-feeding, and 76% that partial breast-feeding was protective compared to no breast-feeding. When infants receiving no breast milk are contrasted with infants on exclusive or partial breast-feeding, the median relative risks are 3.0 for those aged 0-2 months, 2.4 for those ages 3-5 months, and 1.3-1.5 for those aged 6-11 months. Above 1 year of age no protective effects of breast-feeding on diarrhoea morbidity is evident. When infants receiving no breast milk are contrasted with those on exclusive breast-feeding, median relative risks are 3.5-4.9 in the first 6 months of life. The literature does not suggest that the relative risks of diarrhoea morbidity for the bottle-fed infants are higher in poor families than in more wealthy families. The protective effects of breast-feeding do not appear to continue after the cessation of breast-feeding. There is evidence of considerably increased diarrhoea severity among bottle-fed infants. There is a limited, and mostly pre-1950, literature on the relative risks of diarrhoea mortality to infants on different feeding nodes. Nine studies from 5 countries were reviewed most of which showed that breast-feeding protects substantially against death from diarrhoea. When infants receiving no breast milk are contrasted with those on exclusive breast-feeding, the median relative risk of death from diarrhoea during the first 6 months of life is 25. When partially and exclusively breast-fed infants are contrasted, the median relative risk of death from diarrhoea is 8.6. Breast-feeding can be promoted by changes in hospital routine and by giving information and support to mothers. A review of 21 studies from 8 countries show that, by such promotion, the most likely reductions in the prevalence of non-breast-fed infants are 40% among infants aged 0-2 months, 30% among those aged 3-5 months, and 10% among those between 6 months and 1 year old. Theoretical calculations based on these data show that such promotion can reduce diarrhoea morbidity rates by 8-20% and diarrhoea mortality rate by 24-27% in the first 6 months of life. For children aged 0-59 months, diarrhoea morbidity rates would be reduced by 1-4% and mortality rates by 8-9%. A recent study in Costa Rica has documented a substantial impact of breast-feeding promotion on neonatal diarrhoea morbidity and mortality, and on diarrhoea morbidity in infants aged 0-5 months. The Costa Rican data show good agreement with the theoretical computations presented in this paper. Several important aspects of breast-feeding and diarrhoea remain to be clarified by research. However, the need for this research should not delay action to promote breast-feeding and to monitor its effects upon feeding practice and upon diarrhoea.