HIV transmission and breastfeeding
19 February 2008
In developing countries, where most babies depend on breast milk for their survival, HIV transmission from mother to child during breastfeeding is common. Intriguingly, however, researchers at the Africa Centre for Health and Population Studies in South Africa have found that HIV transmission is far lower if mothers feed their children exclusively with breast milk for the first six months than if they also introduce formula milk or solids at this early stage.
In a study of more than 2000 new mothers in rural and urban areas, Professor Hoosen Coovadia and colleagues found that there was a 4 per cent risk of postnatal HIV transmission between the ages of six weeks and six months to babies fed on breast milk alone. Infants who received a mixture of breast milk and formula were nearly twice as likely to be infected as those receiving breast milk only. Alarmingly, those given both breast milk and solids were almost 11 times likelier than the breast-only group to acquire infection.
This unexpected benefit of breast milk may come about because it strengthens the baby’s gut lining. The larger, more complex proteins found in formula, animal milk and solids, by contrast, may damage the intestine, allowing HIV to pass into the bloodstream more effectively.
UNICEF, the World Health Organization and UNAIDS have already revised their guidelines on infant feeding to reflect these findings. This could dramatically reduce the vertical transmission of HIV from mother to child on the African continent and beyond.
Further reading
- Coovadia HM et al. Mother-to-child transmission of HIV-1 infection during exclusive breastfeeding in the first 6 months of life: an intervention cohort study. Lancet 2007;369(9567):1107–16.