Expanding ART for treatment and prevention of HIV in South Africa: estimated cost and cost-effectiveness 2011-2050

Abstract

Background: Antiretroviral Treatment (ART) significantly reduces HIV transmission. We conducted a cost-effectiveness analysis of the impact of expanded ART in South Africa.

Methods: We model a best case scenario of 90% annual HIV testing coverage in adults 15-49 years old and four ART eligibility scenarios: CD4 count <200 cells/mm(3) (current practice), CD4 count <350, CD4 count <500, all CD4 levels. 2011-2050 outcomes include deaths, disability adjusted life years (DALYs), HIV infections, cost, and cost per DALY averted. Service and ART costs reflect South African data and international generic prices. ART reduces transmission by 92%. We conducted sensitivity analyses.

Results: Expanding ART to CD4 count <350 cells/mm(3) prevents an estimated 265,000 (17%) and 1.3 million (15%) new HIV infections over 5 and 40 years, respectively. Cumulative deaths decline 15%, from 12.5 to 10.6 million; DALYs by 14% from 109 to 93 million over 40 years. Costs drop $504 million over 5 years and $3.9 billion over 40 years with breakeven by 2013. Compared with the current scenario, expanding to <500 prevents an additional 585,000 and 3 million new HIV infections over 5 and 40 years, respectively. Expanding to all CD4 levels decreases HIV infections by 3.3 million (45%) and costs by $10 billion over 40 years, with breakeven by 2023. By 2050, using higher ART and monitoring costs, all CD4 levels saves $0.6 billion versus current; other ART scenarios cost $9-194 per DALY averted. If ART reduces transmission by 99%, savings from all CD4 levels reach $17.5 billion. Sensitivity analyses suggest that poor retention and predominant acute phase transmission reduce DALYs averted by 26% and savings by 7%.

Conclusion: Increasing the provision of ART to <350 cells/mm3 may significantly reduce costs while reducing the HIV burden. Feasibility including HIV testing and ART uptake, retention, and adherence should be evaluated.

Figure 1. Key epidemic indicators by ART scenario, over time, enhanced prevention scenario to 2050.

This figure presents key epidemic results. The adult population is the denominator. “Blue” is all CD4 levels, “Yellow” is <500/mm³, “Pink” is <350/mm³, and “Black” is current <200/mm³. The “Incidence rate” graphs show that the rate of new HIV infections drops most sharply with higher ART use due to more inclusive CD4 criteria. The “Prevalence Rate” graphs show a similar but more gradual decline in HIV prevalence with more ART, and also show that differences in ART use in the short term converge over time due to averted infections The “Annual death rate” graph highlights the benefit of expanded ART on death rates.

Figure 2. Lives saved by CD4 treatment threshold compared to current CD4<200 baseline.

Graph shows lives saved by CD4 treatment threshold compared to current CD4<200 baseline with the <350 scenario portrayed in “pink”, <500 in “yellow” and all CD4 in “blue”. Lives saved increase with earlier access to ART.

Figure 3. Annual cost by scenario compared to current prevention scenario baseline, 2010–2050.

This figure shows the annual cost by ART scenario compared to the projected baseline of <200 current scenario. Totals represent cumulative cost savings over 2010–2050 time period. Cost neutral time points cluster around 2015. Discounted savings over 40 years are 3.9, 8.8, and 13.8 billion for <350, <500, and all CD4 cells, respectively.

Figure 4. Average annual costs by category with breakdown of human rights and community support components.

The pie represents the annual costs based on a CD4<350 scenario without additional prevention averaged over 40 years. Care includes hospital and primary health care (excluding nutrition and human rights), which have their own slices in the pie. Outreach represents the costs of the community-based campaign excluding human rights and community support costs. ART represents ARV costs, aboratory and clinic visits are included in Care category. The other categories are self-explanatory and further details can be found in the Information S1 document.

Figure 5. Undiscounted expenditure over 40 years by type of cost and scenario.

These histograms show how projected expenditures over 40 years vary as a function of the ART scenario. As ART intensity rises, overall spending drops, with a modest rise in ARV drug costs and a larger drop in hospital costs.

Figure 6. Difference in spending by ART scenario, 2010–2050 (discounted to 2010).

This bar chart represents the difference in spending between different ART scenarios over 40 years (discounted to 2010). The ART scenario comparison is indicated on the horizontal axis, and the cost difference on the vertical axis (in millions). Negative numbers indicate fewer costs with more use of ART. Findings under current prevention impact are indicated in blue, and under enhanced prevention in maroon. The differences between scenarios are greater for current than enhanced prevention.

Figure 7. Difference in DALYs by ART scenario, 2010–2050 (discounted to 2010).

This bar chart represents the difference in Disability Adjusted Life Years (DALYs) between different ART scenarios, over 40 years (discounted to 2010). The ART scenario comparison is indicated in the horizontal axis label. The DALY difference is indicated on the vertical axis (in thousands). Negative numbers indicate fewer DALYs with more use of ART, representing lower disease burden. Findings with current prevention are indicated in blue, and with enhanced prevention in maroon. The differences between ART scenarios are greater under current prevention impact than assumed enhanced prevention impact.