Background:  We currently provide antiretrovirals (ARV) to 7000 HIV-1-infected patients in Sub-Saharan Africa as part of a comprehensive effort. Pregnant women in our program receive HAART antenatally and continue the regimen throughout the first 6 months of breastfeeding or indefinitely when HAART is initiated because of maternal health. 

Methods:  A prospective cohort study of HIV-1-infected women treated with HAART from the prenatal to the postnatal period is ongoing in Mozambique. Here we report 12-month data on maternal and infant outcomes. Infants were tested for HIV-1 at 1, 6, and 12 months of age using bDNA. Mothers were counselled to exclusively breastfeed until 6 months of age. Additional sources of nutrition were introduced thereafter.

Results:  We enrolled 341 women who initiated ART during pregnancy. During the 12-month postnatal period, 2 women (0.6%) died. Follow-up data were available for 276 of 341 children at 12 months of age (81%); 51 children (15%) were lost to follow-up, and 14 (4.2%) died in the first 12 months of life (7 in the first semester). Of the children who died, 13 had negative HIV bDNA results until the time of death, and 1 was HIV-infected. The observed infant mortality rate was 48.3 per 1000 live births (for Mozambique in 2005, it was 101 per 1000). A small portion of women (2.5%) had a history of prior ARV exposure; 55 women continued HAART beyond 6 months because of baseline CD4 counts <200 or symptomatology (1 transmission at 6 months in this group). The median maternal plasma virus load among infants who acquired HIV infection was 4.38 log at the time of infant diagnosis, as opposed to 3.79 log (Levene test, NS; t-test, NS) in the mothers who did not transmit. No correlation was noted between infant HIV infection and maternal baseline CD4 cell count, virus load, or duration of pre-natal ARV treatment, likely due to the small number of infections noted. New cases of HIV-1 maternal-to-child transmission (MTCT) at different infant ages are reported.  

Conclusions:  Among breastfed children born to women on HAART in the prenatal and postnatal period, HIV-1 MTCT rates were low overall, although higher in the first month. Rates stabilized after 1 month with no increase in transmissions after 6 months following introduction of mixed feedings. Late postnatal transmission of HIV-1 is decreased by maternal use of HAART. The effect appears to be protective until 12 months of age.