Breastmilk, breastfeeding, and transmission of viruses to the neonate.

The benefits of breast milk have been well delineated, and breastfeeding should be encouraged whenever possible. However, the potential transmission of HIV-1, HTLV-1, and possibly HTLV-II warrant the recommendation that women in industrialized countries who are infected with these viruses not breastfeed their infants. These recommendations reflect what is currently known about the risks of viral transmission through breastfeeding; ongoing and future studies may provide additional data, enabling a better definition of the precise risks and factors associated with the transmission of viruses through breastfeeding.