Adolescents and young adults are the most undiagnosed of HIV and virally unsuppressed in Eastern and Southern Africa: Pooled analyses from five population-based surveys.

Age and gender disparities within the HIV cascade of care are critical to focus interventions efficiently. We assessed gender-age groups at the highest probability of unfavorable outcomes in the HIV cascade in five HIV prevalent settings. We performed pooled data analyses from population-based surveys conducted in Kenya, South Africa, Malawi and Zimbabwe between 2012 and 2016. Individuals aged 15-59 years were eligible. Participants were tested for HIV and viral load was measured. The HIV cascade outcomes and the probability of being undiagnosed, untreated among those diagnosed, and virally unsuppressed (≥1,000 copies/mL) among those treated were assessed for several age-gender groups. Among 26,743 participants, 5,221 (19.5%) were HIV-positive (69.9% women, median age 36 years). Of them, 72.8% were previously diagnosed and 56.7% virally suppressed (88.5% among those treated). Among individuals 15-24 years, 51.5% were diagnosed vs 83.0% among 45-59 years, p<0.001. Among 15-24 years diagnosed, 60.6% were treated vs 86.5% among 45-59 years, p<0.001. Among 15-24 years treated, 77.9% were virally suppressed vs 92.0% among 45-59 years, p<0.001. Among all HIV-positive, viral suppression was 32.9% in 15-24 years, 47.9% in 25-34 years, 64.9% in 35-44 years, 70.6% in 45-59 years. Men were less diagnosed than women (65.2% vs 76.0%, p <0.001). Treatment among diagnosed and viral suppression among treated was not different by gender. Compared to women 45-59 years, young people had a higher probability of being undiagnosed (men 15-24 years OR: 37.9, women 15-24 years OR: 12.2), untreated (men 15-24 years OR:2.2, women 15-24 years OR: 5.7) and virally unsuppressed (men 15-24 years OR: 1.6, women 15-24 years OR: 6.6). In these five Eastern and Southern Africa settings, adolescents and young adults had the largest gaps in the HIV cascade. They were less diagnosed, treated, and virally suppressed, than older counterparts. Targeted preventive, testing and treating interventions should be scaled-up.