Determinants of viral suppression among adolescents on antiretroviral treatment in Ehlanzeni district, South Africa: a cross-sectional analysis

BACKGROUND: Achieving undetectable viral load is crucial for the reduction of HIV transmissions, AIDS-related illnesses and death. Adolescents (10 to19 years) living with HIV (ALHIV) on antiretroviral treatment (ART) have worse treatment adherence and lower viral suppression rates compared to adults. We report on the clinical factors associated with viral suppression among ALHIV in the Ehlanzeni district, Mpumalanga in South Africa. METHODS: A cross-sectional analysis was conducted with 9386 ALHIV, aged 10 to 19 years, who were enrolled in 136 ART clinics in the Ehlanzeni district. Clinical and immunological data were obtained from electronic medical records (Tier.net). ALHIV were categorised as having achieved viral suppression if their latest viral load count was < 1000 ribonucleic acid (RNA) copies/mL. Using a backward stepwise approach, a multivariate logistic regression analysis was performed to identify factors independently associated with viral suppression. RESULTS: The mean age of the participants was 14.75 years (SD = 2.9), and 55.43% were female. Mean duration on ART was 72.26 (SD = 42.3) months. Of the 9386 adolescents with viral load results recorded, 74% had achieved viral suppression. After adjusting for other covariates, the likelihood of achieving viral suppression remained significantly higher among ALHIV who were: female (AOR = 1.21, 95% CI 1.05–1.39), and had most recent CD4 count > 200 (AOR = 2.53, 95% CI 2.06–3.11). Furthermore, the likelihood of having viral suppression was lower among adolescents with CD4 count > 200 at baseline (AOR = 0.73, 95% CI 0.61–0.87), and who were switched to second line regimen (AOR = 0.41, 95% CI 0.34–0.49). CONCLUSIONS: Viral suppression amongst ALHIV at 74% is considerably lower than the WHO target of 95%. Of particular concern for intervention is the lower rates of viral suppression amongst male ALHIV. Greater emphasis should be placed to early enrolment of ALHIV on ART and keeping them engaged in care (beyond 6 months). Furthermore, improved and regular viral load monitoring will help to adequately identify and manage ALHIV with unsuppressed viral load and subsequently switching to second line treatment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12981-021-00391-7.