HIV viraemia and mother-to-child transmission risk after antiretroviral therapy initiation in pregnancy in Cape Town, South Africa.

OBJECTIVES: Maternal HIV viral load (VL) drives mother-to-child HIV transmission (MTCT) risk but there are few data from sub-Saharan Africa, where most MTCT occurs. We investigated VL changes during pregnancy and MTCT following antiretroviral therapy (ART) initiation in Cape Town, South Africa. METHODS: We conducted a prospective study of HIV-infected women initiating ART within routine antenatal services in a primary care setting. VL measurements were taken before ART initiation and up to three more times within 7 days postpartum. Analyses examined VL changes over time, viral suppression (VS) at delivery, and early MTCT based on polymerase chain reaction (PCR) testing up to 8 weeks of age. RESULTS: A total of 620 ART-eligible HIV-infected pregnant women initiated ART, with 2425 VL measurements by delivery (median gestation at initiation, 20 weeks; median pre-ART VL, 4.0 log10 HIV-1 RNA copies/mL; median time on ART before delivery, 118 days). At delivery, 91% and 73% of women had VL ≤ 1000 and ≤ 50 copies/mL, respectively. VS was strongly predicted by time on therapy and pre-ART VL. The risk of early MTCT was strongly associated with delivery VL, with risks of 0.25, 2.0 and 8.5% among women with VL < 50, 50-1000 and > 1000 copies/mL at delivery, respectively (P < 0.001). CONCLUSIONS: High rates of VS at delivery and low rates of MTCT can be achieved in a routine care setting in sub-Saharan Africa, indicating the effectiveness of currently recommended ART regimens. Women initiating ART late in pregnancy and with high VL appear substantially less likely to achieve VS and require targeted research and programmatic attention.

Burden of tuberculosis in HIV-positive pregnant women in Cape Town, South Africa.

BACKGROUND: The burden of active tuberculosis (TB) in pregnancy compared with preconception and postpartum is unclear, particularly with universal antiretroviral therapy (ART) initiation in pregnancy. METHODS: We retrospectively compared active TB incidence in the 18 months preconception, during pregnancy and up to 6 months postpartum in human immunodeficiency virus (HIV) positive women attending antenatal care at a primary health care facility in Cape Town from 2013 to 2014. RESULTS: Among 1513 women (4116 person-years [py]), 1489 (98.4%) received lifelong ART in pregnancy, and 79 TB episodes were identified. Unadjusted TB incidence rates (IR) preconception, during pregnancy and postpartum were 2466 (95%CI 1863-3202), 1127 (95% CI 600-1928) and 1447 (95% CI 694-2661) per 100 000 py, respectively. Adjusting for age and CD4 count at first antenatal visit and ART status, TB risk was lower during pregnancy (incidence rate ratio [IRR] 0.17 vs. preconception, 95%CI 0.09-0.31) and increased slightly postpartum (IRR 1.31 vs. pregnancy, 95%CI 0.56-3.07). CONCLUSION: Among HIV-positive women in South Africa, the TB burden preconception, during pregnancy and postpartum was substantial. The risk of TB during pregnancy was lower than preconception, but increased slightly postpartum; this represents missed opportunities for diagnosis, prevention and control. Improved TB prevention strategies and integrated care for HIV-positive women and their children are needed.