Viral suppression among pregnant adolescents and women living with HIV in rural KwaZulu-Natal, South Africa: a cross sectional study to assess progress towards UNAIDS indicators and Implications for HIV Epidemic Control

BACKGROUND: South Africa has made significant progress in scaling up antiretroviral therapy (ART) to achieve the aspirational goal of HIV epidemic control. The aim of this study was to determine the prevalence of HIV, assess progress towards each of the Joint United Nations Programme on HIV/AIDS (UNAIDS) indicators and determine factors associated with achieving viral suppression among pregnant adolescents and women living with HIV in rural KwaZulu-Natal, South Africa. METHODS: Pregnant adolescents and women, 12 years and older seeking antenatal care at six primary health care clinics were enrolled in a cross-sectional study. Following written informed consent, structured questionnaires were administered, and finger-prick blood samples were collected for HIV antibody testing and viral load measurement. Viral suppression was defined as HIV viral load of < 400 copies per mL. RESULTS: Between Dec 2016 and March 2017, among the 546 enrolled participants, data for 545 were analysed. The overall HIV prevalence was 40.2% [95% Confidence Interval (CI) 36.1–44.3]. Age-stratified prevalence increased from 22.1% (95% CI, 15.9–30.0) in the 14–19 year age group to 63.9% (95% CI, 55.1–71.9) among women ≥ 30 years (Χ(2) trend P < 0.0001). Of the HIV positive participants, 84.5% (95% CI, 79.0–88.8) knew their HIV positive status, 98.3% (95% CI 95.1–99.4) who knew their status were on ART, and of those on ART, 95.9% (95% CI 91.8–98.0) were virally suppressed. Among all HIV-positives 90.8% (95% CI, 86.3–94.0) had achieved viral suppression, whilst those in the 14–19 year age group were least likely to be virally suppressed at 82.8% (95% CI 65.5–92.4) compared to those in the older age groups. Married women compared to those unmarried were more likely to have achieved viral suppression (PRR) of 1.11 (95% CI 1.05–1.18), P < 0.001. CONCLUSIONS: The proportion of HIV positive pregnant women achieving viral suppression was encouraging though far short of the target towards achieving epidemic control. Importantly, adolescent pregnant women were less likely to know their HIV status and to achieve viral suppression, underscoring the public health implications of sustained risk of HIV transmission. Thus, greater effort and strong social support are essential to improve HIV knowledge of status and care continuum towards the goal to achieving HIV epidemic control. PLAIN LANGUAGE SUMMARY: To “fast-track” the response to achieve HIV epidemic control and end the AIDS epidemic, the Joint United Nations Programme on HIV/AIDS (UNAIDS) set ambitious HIV testing and treatment targets for people living with HIV. Meeting these targets through scaling up testing for HIV, initiating and sustaining antiretroviral therapy (ART) to maintain viral suppression provides both therapeutic and preventive benefits with the potential to reduce HIV transmission. Viral suppression among pregnant adolescents and women living with HIV is crucial for the prevention of mother-to-child transmission of HIV including onward transmission to sexual partners. As a public health approach, in South Africa all pregnant women are offered routine HIV testing and immediate initiation of lifelong ART irrespective of CD4 cell count. It is, therefore, important to ascertain progress towards reaching the targets. The proportion of HIV positive pregnant adolescents and women achieving viral suppression was encouraging though far short of the target towards achieving epidemic control. Importantly, pregnant adolescents were less likely to know their HIV status and to achieve viral suppression, underscoring the public health implications of sustained risk of HIV transmission. Thus, greater effort and strong social support are essential to improve HIV knowledge of status and care continuum towards the goal to achieving HIV epidemic control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12978-022-01419-5.