Exclusive breastfeeding protects against HIV transmission

South African study1 presents first evidence of impact of exclusive breastfeeding on vertical transmission.

Breastfeeding experts from around the world have been waiting for results of this prospective study from South Africa on the impact of exclusive breastfeeding on mother-to-child transmission of HIV.

Results confirm what many of us had anticipated, that exclusive breastfeeding would exert a protective effect on the infant's gut lining, minimizing the risk of HIV transmission via the gut wall.

When exclusive breastfeeding is not practised during the early months of infancy i.e. other foods and fluids are given, damage to the gut surfaces by various means can occur. The damaged mucosal surfaces are then more vulnerable to infection, allergens or physical trauma and thus allow passage of the HIV across the membrane and into the body tissues.

Researchers, Coutsoudis et al., using a rigorous definition of exclusive breastfeeding concluded that when breastfeeding is exclusive from birth, it does not appear to transmit HIV from
an HIV-positive mother to an HIV-negative infant. This prospective cohort study found that transmission rates among those exclusively breastfed from birth were lower at three months than among those not breastfed at all and much lower than those breastfed but not exclusively. The authors noted that this "raises the possibility that virus acquired during delivery could have been neutralized by immune factors present in breastmilk but not in formula feeds."

This work should have significant impact on the UNAIDS/WHO/UNICEF controversial guidelines on infant feeding and HIV. This should lead to a reassessment of the recommendations to modifying the risky reintroduction of infant formulas in areas of the world where these products significantly increase infant and young child mortality rates.

Clearly more research is needed to continue the exploration and elaborate these exciting results.

Reference:
1. Coutsoudis, A. et al. Influence of infant feeding patterns on early mother-to-child transmission of HIV-1 in Durban, South Africa: a prospective cohort study. The Lancet 354: Aug 7, 1999 BACK