The potential impact of expanding antiretroviral therapy and combination prevention in Vietnam: towards elimination of HIV transmission

Abstract

Background: Few studies have assessed the effects of antiretroviral therapy (ART) to prevent HIV transmission in Asian HIV epidemics. Vietnam has a concentrated HIV epidemic with the highest prevalence among people who inject drugs. We investigated the impact of expanded HIV testing and counseling (HTC) and early ART, combined with other prevention interventions on HIV transmission.

Methods: A deterministic mathematical model was developed using HIV prevalence trends in Can Tho province, Vietnam. Scenarios included offering periodic HTC and immediate ART with and without targeting subpopulations and examining combined strategies with methadone maintenance therapy and condom use.

Results: From 2011 to 2050, maintaining current interventions will incur an estimated 18,115 new HIV infections and will cost US $22.1 million (reference scenario). Annual HTC and immediate treatment, if offered to all adults, will reduce new HIV infections by 14,513 (80%) and will cost US $76.9 million. Annual HTC and immediate treatment offered only to people who inject drugs will reduce new infections by 13,578 (75%) and will cost only US $23.6 million. Annual HTC and immediate treatment for key populations, combined with scale-up of methadone maintenance therapy and condom use, will reduce new infections by 14,723 (81%) with similar costs (US $22.7 million). This combination prevention scenario will reduce the incidence to less than 1 per 100,000 in 14 years and will result in a relative cost saving after 19 years.

Conclusions: Targeted periodic HTC and immediate ART combined with other interventions is cost-effective and could lead to potential elimination of HIV in Can Tho.

Conflict of interest statement

The authors have no conflicts of interest to disclose.

Figures

FIGURE 1

Schematic diagram showing the links between the different subpopulations in the model. Red arrow shows HIV transmission via needle sharing, green arrow shows sexual transmission among MSM, and blue arrow shows heterosexual transmission. The groups coloured pink indicate that HIV transmission happens within the group.

FIGURE 2

Annual new HIV infection (A), AIDS death (B), and ART and HTC cost (C) with 3 potential policy scenarios. Reference scenario assumes current coverage of ART, and other prevention interventions are maintained at the level in 2010. Combination prevention scale-up assumes expansion of MMT, condom use, and ART. In the last scenario, PTIT focusing on 3 key populations, that is, PWID, FSW, and MSM, was added to combination prevention scale-up.

FIGURE 3

Cumulative DALY saved and cost of HTC and ART from 2011 to 2050 of 13 analyzed scenarios. Brown box refers to universal PTIT scenarios with varying HTC interval (2 year, 1 year, and 6 months). Blue diamond refers to targeted PTIT scenarios with annual HTC focusing on single subpopulations (PWID, FSW, MSM, MCF, and LRW). SA, standard ART scale-up to 90% of those with CD4 below 350 cells per cubic millimeter. Combination + ART 350, combination prevention scale-up with standard ART. Combination + PTIT, combination prevention scale-up with PTIT for PWID, FSW, and MSM.