Exclusive breastfeeding and HIV

Earlier estimates that the risk of postnatal transmission is between 10% and 20% did not distinguish between exclusive and mixed breastfeeding.28 In 1998, the first report that exclusive breastfeeding might reduce the risk came from a vitamin A trial in South Africa.9 In 2005, a large trial in Zimbabwe showed that HIV transmission with mixed feeding was more than three times that with exclusive breastfeeding by 6 months of age.10 Although also observational, Coovadia and colleagues' study is the first in which measurement of transmission by feeding method was the primary aim. Coovadia and colleagues' findings enable infant feeding guidelines for HIV-positive pregnant women to be refined.11 However, the results also emphasise that promotion of exclusive breastfeeding for all mothers and babies could prevent much paediatric HIV infection as well as deaths from other causes.