Infant feeding: emerging concepts to prevent HIV transmission

HIV screening in pregnancy, universal suppressive antiretroviral therapy (ART) and breastfeeding avoidance can almost completely prevent vertical transmission of HIV. Breastfeeding is associated with an additional risk of transmission, although this risk is extremely low with suppressive maternal ART. This minimal risk must be balanced with the benefits of breastfeeding for women living with HIV (WLHIV) and their infants. Guidance in high-income countries has evolved, moving towards supported breast feeding for women on suppressive ART.

Breastmilk transmission accounts for an increasing proportion of new infant infections globally. The majority of transmission data comes from studies including women not on suppressive ART. Breastmilk transmissions in the context of undetectable viral load have rarely occurred, although risk factors remain unclear. Outcome data on supported breastfeeding are accumulating, providing evidence for guidelines and informing infant feeding decisions. Long-acting ART for maternal preexposure prophylaxis or treatment, and infant postnatal prophylaxis are promising future options.

Breastfeeding on suppressive ART has a very low risk of vertical transmission and can have multiple benefits for WLHIV and their infants. However, caution is advised with relaxation of breastfeeding guidance so as not to jeopardise the global goal of elimination of vertical transmission by 2030.