Achieving the UNAIDS 90-90-90 targets for getting more people with HIV tested and on effective treatment in South Africa would cost nearly $16bn over 10 years, but could avert more than 2m new HIV infections and prevent 2.5m deaths, according to a mathematical model analysis.
The UNAIDS 90-90-90 targets aim to have 90% of people with HIV aware of their status, 90% of those receiving antiretroviral therapy (ART), and 90% of people on treatment having undetectable viral load – that is, 73% of people with HIV having viral suppression.
UNAIDS recently announced that an estimated 17m people living with HIV are now on ART, including 3.4m in South Africa. ART can halt HIV disease progression, prolong survival, and prevent onward HIV transmission. But today around half of people with HIV are not yet on treatment and only about 30% are thought to have viral suppression.
Rochelle Walensky from Massachusetts General Hospital and colleagues estimated the clinical and economic value of reaching the 90-90-90 goals in South Africa, using a micro-simulation model of HIV detection, disease, and treatment. The researchers used published estimates and South African survey data on HIV transmission rates (0.16 to 9.03 per 100 person-years), HIV-specific age-stratified fertility rates (1.0 to 9.1 per 100 person-years), and costs of care ($11 to $31 per month for ART and $20 to $157 per month for routine care).
They compared a “current pace” strategy assuming existing scale-up efforts and gradual increases in viral suppression from 24% to 36% in 5 years, versus the “90-90-90 strategy” assuming 73% viral suppression in 5 years. The latter strategy would involve aggressive HIV case detection, efficient linkage to care, rapid ART scale-up, and adherence and retention interventions. The model assumed that most people would respond well to treatment and stay on it.
Using these parameters, Walensky’s team made projections for HIV transmissions, deaths, years of life saved, the number of children who would become orphans when their mothers died, costs (in 2014 US dollars), and cost-effectiveness over 5- and 10-year time horizons.
Looking first at the 5-year horizon, the researchers calculated that the 90-90-90 strategy, compared to the current pace, would: avert 873,000 HIV transmissions; prevent 1,174,000 deaths; keep 726,000 children from becoming maternal orphans; and save 3,002,000 life-years.
Over 10 years the 90-90-90 strategy would: avert 2,051,000 new HIV infections; prevent 2,478,000 deaths; keep 1,689,000 children from becoming orphans; and save 13,340,000 life-years.
The estimated additional cost required for the 90-90-90 strategy would be $7.97bn over 5 years and $15.98bn over 10 years – about a 40% increase over current funding levels. This would yield incremental cost-effectiveness ratios of $2,720 per quality-adjusted year of life saved over 5 years, falling to $1,260 over 10 years.
The researchers noted that outcomes generally varied by less than 20% from these base-case outcomes when key parameters were varied within “plausible ranges.” They suggested that achieving the 90-90-90 levels would necessitate screening the entire South African population as often as every 2 years.
“Reaching the 90-90-90 HIV suppression target would be costly but very effective and cost-effective in South Africa,” the study authors concluded. “Global health policymakers should mobilize the political and economic support to realise this target.”
Background: The Joint United Nations Programme on HIV/AIDS (UNAIDS) 90–90–90 global treatment target aims to achieve 73% virologic suppression among HIV-infected persons worldwide by 2020.
Objective: To estimate the clinical and economic value of reaching this ambitious goal in South Africa, by using a microsimulation model of HIV detection, disease, and treatment.
Design: Modeling of the “current pace” strategy, which simulates existing scale-up efforts and gradual increases in overall virologic suppression from 24% to 36% in 5 years, and the UNAIDS target strategy, which simulates 73% virologic suppression in 5 years.
Data Sources: Published estimates and South African survey data on HIV transmission rates (0.16 to 9.03 per 100 person-years), HIV-specific age-stratified fertility rates (1.0 to 9.1 per 100 person-years), and costs of care ($11 to $31 per month for antiretroviral therapy and $20 to $157 per month for routine care).
Target Population: South African HIV-infected population, including incident infections over the next 10 years.
Perspective: Modified societal perspective, excluding time and productivity costs.
Time Horizon: 5 and 10 years.
Intervention: Aggressive HIV case detection, efficient linkage to care, rapid treatment scale-up, and adherence and retention interventions toward the UNAIDS target strategy.
Outcome Measures: HIV transmissions, deaths, years of life saved, maternal orphans, costs (2014 U.S. dollars), and cost-effectiveness.
Results of Base-Case Analysis: Compared with the current pace strategy, over 5 years, the UNAIDS target strategy would avert 873 000 HIV transmissions, 1 174 000 deaths, and 726 000 maternal orphans while saving 3 002 000 life-years; over 10 years, it would avert 2 051 000 HIV transmissions, 2 478 000 deaths, and 1 689 000 maternal orphans while saving 13 340 000 life-years. The additional budget required for the UNAIDS target strategy would be $7.965 billion over 5 years and $15.979 billion over 10 years, yielding an incremental cost-effectiveness ratio of $2720 and $1260 per year of life saved, respectively.
Results of Sensitivity Analysis: Outcomes generally varied less than 20% from base-case outcomes when key input parameters were varied within plausible ranges.
Limitation: Several pathways may lead to 73% overall virologic suppression; these were examined in sensitivity analyses.
Conclusion: Reaching the 90–90–90 HIV suppression target would be costly but very effective and cost-effective in South Africa. Global health policymakers should mobilize the political and economic support to realize this target.
Rochelle P Walensky; Ethan D Borre; Linda-Gail Bekker; Stephen C Resch; Emily P Hyle; Robin Wood; Milton C Weinstein; Andrea L Ciaranello; Kenneth A Freedberg; and A David Paltiel