Scaling up HIV treatment for MSM in Bangkok : what does it take? – a modelling and costing study

96523 Scaling up HIV treatment for MSM in Bangkok: what does it take? —— a modelling and costing study Lei Zhang1, Nittaya Phanuphak2, Klara Henderson1, Siriporn Nonenoy2, Sasiwan Srikaew2, Andrew J Shattock1, Cliff C. Kerr1, Brenda Omune2, Frits van Griensven2, Sutayut Osornprasop3, Robert Oelrichs3, Jintanat Ananworanich2,4, David P Wilson1 1 The Kirby Institute, The University of New South Wales, Australia 2 Thai Red Cross Society AIDS Research Center, Bangkok, Thailand 3 The World Bank Group, Washington, United Sates should be States 4 Current address: U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA Scaling up HIV treatment for MSM in Bangkok: what does it take? Table of Contents Executive Summary .............................................................................................................. 6 Background ......................................................................................................................... 10 Methodology ........................................................................................................................ 13 Data collation and synthesis ......................................................................................... 13 Modelling methodology .............................................................................................. 14 Forecasting epidemiological impacts and cost-effectiveness ...................................... 15 Key findings ........................................................................................................................ 17 Finding 1: Low HIV testing and treatment linkages in Bangkok MSM ..................... 17 Finding 2: High HIV testing service and treatment availability in Bangkok ............. 17 medical facilities Finding 3: Spending on linkage and service provision for Bangkok MSM ................... 18 Finding 4: Significant epidemiological benefits in HIV testing and ART ........................ 21 services scale-up Finding 5: Services scale-up are economical and cost-saving ........................................ 23 Discussion ............................................................................................................................ 27 Conclusion ........................................................................................................................... 30 Appendix.............................................................................................................................. 32 References ............................................................................................................................ 59 List of Tables Table 1 Current operational load and capacity availability of Bangkok medical facilities in providing HIV testing and ART services ........................................................................... 18 Table 2 Estimated investments on HIV testing and ART services among MSM in Bangkok, expected epidemiological outcomes and cost benefits during 2013-2022 ........................... 25 Table S1: Assessment of service provision and capacity of HIV testing and ART sites in Bangkok. ..........35 Table S2: Disability weights for HIV related health states from the 2010 Global Burden...........................42 of Disease Study Table S3: Assumed disability-weights for DALY calculations. The disability-weight for HIV-positive .....42 MSM is the maximum of the value for HIV-negative MSM and the corresponding HIV-positive category disability weight. Table S4: Facility characteristics and operational capacity of HIV testing services ....................................43 in 91 Bangkok medical facilities. Site information was obtained from the National Health Security Office (NHSO) database, service load and capacity data from capacity assessment survey, and distance information from site mapping exercise. Table S5: Facility characteristics and operational capacity of ART services ................................................47 in 48 Bangkok medical facilities. Data was obtained from the National Health Security Office (NHSO), Thailand THE WORLD BANK GROUP Table S6: Service load and capacity for (a) HIV testing services in 91 and (b) ART services .....................49 in 48 Bangkok medical clinics in 2011, stratified by facility types and distances to MSM hotspots. Table S7: Strategies and costs in linking high-risk MSM to HIV testing services in Bangkok. ...................50 Table S7a: Cost of linking high-risk MSM to HIV testing services ...................................................50 using community-based outreach through peer-educators Table S7b: Cost of linking high-risk MSM to HIV testing services....................................................51 using mobile point-of-care night clinics Table S7c: Cost of linking high-risk MSM to HIV testing services using Adam's Love website. ......52 Table S8: Cost distribution for HIV testing service provision in 13 Bangkok medical................................53 facilities in 2011. Table S9: Cost of linking high-risk diagnosed HIV+ MSM to ART services using.....................................54 the Case Management Model Table S10: Cost distribution for ART service provision in 13 Bangkok medical facilities in 2011. ...............55 List of Figures Figure 1 Low HIV testing and ART commencement rates among high-risk MSM in Bangkok .............................................................................................................................. 17 Figure 2 Strategies and costs for linkage and services provision of HIV testing and treatment among MSM in Bangkok. .................................................................................................. 19 Figure 3 Cost breakdown for HIV testing and ART services provision in Bangkok facilities .............................................................................................................................. 20 Figure 4 Projected epidemiological outcomes for scenarios of achieving universal ART coverage (80%) among MSM (undiagnosed and diagnosed) in Bangkok in 3, 5 and 10 years. .................................................................................................................................. 22 Figure 5 The most economical strategies to scale-up (a) HIV testing; (b) ART services among MSM in Bangkok. ............................................................................................................... 24 Figure S1: Low HIV testing and ART commencement rates among high-risk MSM in Bangkok. ...............34 Figure S3: HIV Infection Progression. ............................................................................................................37 Figure S4: Calibration of Optima to the HIV epidemic among MSM in Bangkok during ............................39 2000-2012 , (a) HIV prevalence; (b) number of diagnosed HIV+ MSM on ART Figure S5: Projected decline trend in the unit cost for HIV testing and ART provision in ............................56 relation to service capacity in Bangkok medical facilities. The solid dots present current service load and corresponding estimated unit costs. Scaling up HIV treatment for MSM in Bangkok: what does it take? Abbreviations AEM AIDS Epidemic Model ART Antiretroviral therapy BMA Bangkok Metropolitan Administration CEA Cost-effectiveness Analysis CI Confidence interval DALY Disability-adjusted life year FSW Female sex worker MARP Most-at-risk population MOH Ministry of Health MSM Men who have sex with men NHSO National Health Security Office POC Point-of-care PLHIV People living with HIV PWID People who inject drugs STI Sexually transmitted infections TRCARC Thai Red Cross AIDS Research Center UNAIDS Joint United Nations Programme on HIV/AIDS UNPD United Nations Political Declaration on HIV/AIDS VCT Voluntary counseling and testing WB World Bank WHO World Health Organization THE WORLD BANK GROUP  THE WORLD BANK GROUP Executive Summary Scaling up HIV treatment for MSM in Bangkok: what does it take?  Executive Summary Background: The HIV epidemic amongst men who have sex with men (MSM) in Bangkok is substantial. The population size of MSM in Bangkok is 120,000-250,000, with approximately one-third (33.5 percent) considered high-risk, characterized by their young age, multiple partnerships, frequent unprotected anal intercourse, and sexual activities around MSM hotspots. In metropolitan Bangkok, HIV prevalence among MSM reportedly increased from 21 percent to 28 percent between 2000 and 2012. The Thai Working Group of Estimation and Projection (2013) projected an estimate of 39,000 new HIV infections would occur in Thailand during 2012-2016, based on the AIDS Epidemic Model (AEM). MSM will account for 44 percent of these new HIV cases, and 25-30 percent of these infections will likely to occur in Bangkok. In 2011, the United Nations held a high-level meeting on HIV/AIDS where they adopted the ambitious epidemio- logical targets of the United Nations Political Declaration on HIV/AIDS (UNPD), to be met by 2015. Attaining these specific targets would lead to substantial progress towards ending AIDS. UNAIDS has also been prioritizing the “Getting to Zero” initiative (“Zero new HIV infections. Zero AIDS-related deaths. Zero discrimination.”). The Bangkok Metropolitan Administration (BMA) recently responded with the “Bangkok: Getting to Zero” initiative, which strategizes an increased focus on prevention amongst MSM in the city. The clinical trial, HPTN052, demonstrated a 96 percent reduction of HIV transmission among heterosexual discordant couples who received ART. “Treatment as prevention” has become an increasingly accepted strategy to prevent new infections. A cost-effectiveness analysis comparing current levels of investment in targeted HIV prevention interventions for MSM in Bangkok (including treatment), with scenarios of increased coverage, would provide evidence to shape efficient national and metropolitan strategies. A return-on-investment analysis would provide an economic rationale to finance this strategy in allocating sufficient resources to address the epidemic at the most appropriate scale. Demonstra- tion by the study that a significant reduction in transmission (including potential elimination) are both feasible and cost effective, may galvanize global political support. Study objectives: • To assess the cost, service load, and capacity of Bangkok’s health facilities for linking and providing HIV testing and ART programs to MSM; • To identify the most effective and cost-effective strategy to allocate available and additional resources to in order to achieve universal ART coverage (80 percent of treatment-eligible) and minimize the number of new HIV cases and related deaths among Bangkok MSM. Key findings: • HIV testing and treatment coverage in Bangkok MSM has been low. Approximately 61,975 (40,200-83,750) MSM are considered high-risk (defined as those engaged in unprotected anal intercourse in the past three months), but only 14,387 (23 percent) were tested for HIV in 2011. Among those tested, 75 percent of tests were conducted in a Thai Red Cross Anonymous Clinic or Silom Community Clinic. The National Health Security Office (NSHO) reported 989 MSM initiated ART in 2011, corresponding to 30 percent of those diagnosed and treatment-eligible. • In 2012, the estimated ART coverage was 19.8 percent among undiagnosed and diagnosed treatment-eligible MSM (2013 WHO treatment threshold, 500/ml). • Medical facilities in Bangkok had high spare capacity in HIV testing and ART services. On average, 5.3 percent, 39.1 percent, 72.9 percent, and 89.4 percent of HIV testing capacity 6 THE WORLD BANK GROUP  in research clinics, public facilities, BMA health centers, and private hospitals were unfilled respectively. This corresponds to an additional 405,144 HIV tests that can be carried out per year in metropolitan Bangkok by further utilizing available infrastructure. • Existing ART infrastructure in public and private hospitals can be further utilized, with about 48 percent and 36 percent currently used. This means that a total of 94,384 available spaces for further ART expansion. • Existing recruiting strategies require an average of $36 to link an MSM to HIV testing services. Public facilities had the lowest unit cost ($15/test) in providing HIV testing services, followed by research clinics ($33/test), BMA health centers ($34/test) and private hospitals ($40/test). • The peer-driven “Case Management Model” cost $177 to follow one diagnosed and treatment-eligible MSM case to ART initiation. On average, the cost for ART provision per person-year was 23.3 percent lower in public facilities ($1,220) than in private hospitals ($1,587). • Sustaining current rates of HIV testing and ART provision will require $73.8m in investments over the next decade, and lead to ART coverage of 44.2 percent by 2022. However, an additional $55.3m during the same period will increase ART coverage to 80 percent (universal coverage) by 2022. • To achieve universal coverage by 2022, 46,700 (30,300-63,200) MSM would need to be linked to HIV testing, and 197,100 (127,800-266,300) tests would need to be conducted. This enables an extra 12,600 (8,800-16,600) eligible MSM to be linked to ART with 101,000 (70,100-132,400) ART person-years. As a result, by 2022, an estimated 5,100 (3,600-6,700) HIV-related deaths and 3,700 (2,600-4,900) new cases would be averted, corresponding to a 53.0 percent and 35.0 percent reduction respectively, in comparison with the cases in 2012, attaining the UNPD goals (by 2022) in Bangkok MSM. • ART expansion to universal coverage by 2022 is highly cost-effective. The costs for each averted HIV-related death, new infection, and DALY are $10,809 (9,071-13,274), $14,783 (12,398-17,960), and $351 (290-424) respectively. Summary and recommendations: • One-third of MSM is considered high-risk; it is important to prioritize limited health resources to specifically target the highest risk MSM. • Current HIV testing and ART coverage is very low among MSM in Bangkok, rapid scale-up of corresponding services is a high priority. • Overall, Bangkok medical facilities have large spare capacities of HIV testing and ART provision to enable substantial expansion of ART coverage. • Over 75 percent of HIV tests among MSM have been conducted in two research clinics whose remaining available capacity is low. The burden of testing service provisions needs to be shifted to other medical facilities. Public facilities have the lowest unit cost ($15/test) for testing service provisions and sufficient spare testing capacity for shifting of service load. Together with its lower unit cost for ART provision (in comparison with private hospitals), public facilities will play a unique and irreplaceable role for ART scale-up among Bangkok MSM. Drawing from the successful experiences of research clinics will enable the creation of a patient-friendly environment in public facilities. Involving experts from research clinics and MSM community representatives in the implementation and management of services delivery in public facilities will improve the overall service quality. Scaling up HIV treatment for MSM in Bangkok: what does it take? 7  • It is beneficial to employ multiple recruitment methods to link MSM to HIV testing services. However, the currently low ART coverage implies an inefficient link between positive diagnosis and ART initiation. The piloted “Case Management Model,” through peer follow-up, has been shown to be effective in connecting diagnosed individuals to ART initiation and may be a potential strategy for further expansion. • The current level of investment into HIV testing and ART service will not achieve UNPD goals by 2022. However, a moderate increase in investments will enable the achievement of universal ART coverage by 2022 and halve new HIV cases and HIV-related deaths over the same period. In addition, ART expansion to universal coverage by 2022 is highly cost-effective and therefore should be considered as an effective strategy for implementation. • Early achievement of universal ART coverage among MSM in Bangkok will result in even greater epidemiological benefits. • Investment for HIV responses among MSM in Thailand is under-funded. More importantly, due to persistent social stigma, MSM are often afraid of being seen by peers as well as discriminated against by healthcare workers when receiving HIV tests. Stigma and discrimination is the most important barrier preventing scale-up of services for MSM. 8 THE WORLD BANK GROUP  THE WORLD BANK GROUP Background Scaling up HIV treatment for MSM in Bangkok: what does it take?  Background Thailand is one of the countries in Asia that is most severely affected by the HIV epidemic, but effective intervention programs have contained the epidemics in most of the Thai populations. During 2006-2011, HIV prevalence among female sex workers and people who inject drugs substantially decreased from 5.7 percent and 40.0 percent, to 3.2 percent and 26.6 percent respectively [1], while prevalence in general low-risk population observed a slight reduction from 1.4 percent to 1.3 percent. In contrast, HIV prevalence among MSM remained between 20-30 percent across the country [1]. In metropolitan Bangkok, HIV prevalence among MSM reportedly increased from 21 percent to 28 percent [2-7]. The Thai Working Group of Estimation and Projection (2013) project an estimate of 39,000 new HIV infections will occur in Thailand during 2012-2016 based on AIDS Epidemic Model (AEM). Men who have sex with men (MSM) will account for 40 percent of these new HIV cases, and 25-30 percent of these infections will happen in Bangkok [8]. The National Strategic Plan for HIV for this same period aims to reduce the number of new infections by two-thirds from the estimate, and reduce number of deaths in people living with HIV (PLHIV) by more than 50 percent. In 2011, the United Nations high-level meeting on HIV/AIDS adopted the epidemiological targets of the UN Political Declaration to be met by 2015. The goals include reducing both HIV new infections and HIV-related mortality by 2015, and limiting mother-to-child transmission of HIV to below five percent among breastfeeding and two percent among non-breastfeeding women. Although attaining these specific targets will lead to substantial progress towards ending AIDS, achieving them by 2015 is no longer possible. This study investigates the financial commitment required to halve HIV-related deaths and new infections over the period of 2013-2022. The epidemic of HIV amongst MSM in Bangkok is severe and substantial. The population size of MSM has been estimated between 120,000 and 250,000, accounting for one-fourth of the MSM population in Thailand [9]. Approximately one-third (33.5 percent) of Bangkok MSM has been considered as high-risk, characterized by their young age, multiple partnerships, frequent unprotected condom use, and appearance in MSM hotspots where they practiced high-risk sexual activities. Alarmingly high rates of incidence have been detected among high-risk MSM (7.7 per 100 person-years in 2007 [2]). MSM are encouraged to take up HIV testing twice a year, as public and research clinics provide free HIV testing. Antiretroviral therapy (ART) is procured centrally from the Thai Government Pharmaceutical Organization to all ART sites. According to the National AIDS Program (NAP) database, until March 2013, the National Health Security Office (NHSO) program covered care and treatment for 79.5 percent of PLHIV in Thailand, while 16.9 percent are covered under the Social Security Office program, 2.6 percent under Civil Servant Medical Benefit Schemes, and only one percent under other categories, such as self-pay or research studies. CD4 count threshold for ART eligibility in Thailand during the study period is less than 350 cells/mm3, although the country is moving towards ART regardless of CD4 in fiscal year 2015. Curbing the epidemic in this high-risk subgroup will reduce the overall epidemic trend in the broader population. The long-term costs of this unchecked epidemic will be substantial in treatment, and other health related costs, as well as potential impacts on productivity. Despite this, investment in prevention for MSM has been modest, accounting for only 1.3 percent of the total proposed budget in the 10th National HIV Plan (for years 2007-2011). The Bangkok Met- ropolitan Administration (BMA) has recently responded to this important public health problem with the “Bangkok: Getting to Zero” initiative, which strategizes an increased focus on prevention amongst MSM in the city. A recent study by the World Bank demonstrated that, at a global level, 10 THE WORLD BANK GROUP comprehensive preventative interventions for MSM (including treatment) are both cost-effective and will have a significant impact on diminishing the growth of HIV epidemics within general national populations [10]. A cost-effectiveness analysis comparing current levels of investment in targeted HIV prevention interventions for MSM in Bangkok (including treatment), with scenar- ios of increased coverage, would provide evidence to shape efficient national and metropolitan strategies. A return-on-investment analysis would provide an economic rationale to finance this strategy by allocating sufficient resources to address the epidemic at the most appropriate scale. Demonstration by the study that a significant reduction in transmission (including potential elim- ination) are both feasible and cost effective, may galvanize global political support. Despite these initiatives, societal stigma and discrimination against MSM is still widely prevalent in Thailand and undermines the HIV response effort. HIV-positive MSM may experience stigma due to both their sexual orientation and infection status (8). Among Thai MSM, being stigmatised is cited as one of the major reasons for poor treatment received from primary care (9), poor uptake of vol- untary HIV testing, lack of serostatus disclosure to partners (10), delay in access to health care (11), depression and isolation (12). In 2008, a review of economic evaluation literature relating to Thailand revealed inadequate resources and capacity in conducting domestic assessments. It was found that the majority of cost-outcome studies were subject to bias, as they relied on low-quality evidence [11]. A need for high quality and standardized methodology was identified, and the Health Intervention and Technology Assessment Program (HITAP) published the National Methodological Guidelines for Health Technology Assessment and economic evaluation of health interventions [12]. Options under the scenarios of increased coverage will be developed in line with Treatment 2.0 priority areas, which aim to increase coverage in an environment of fiscal constraint. Responding to the HIV epidemic and political momentum, this study focus particularly on high-risk MSM in Bang- kok the following objectives: (1) assess the cost, service load and capacity of Bangkok’s health facilities for linking and providing HIV testing and ART programs to MSM at high risk of HIV; (2) identify the most effective strategy, based on costs of service provision, to allocate available and additional resources to achieve ‘universal’ ART coverage (80 percent of treatment-eligible) and minimise the number of new HIV cases and HIV-related deaths among MSM in Bangkok. Scaling up HIV treatment for MSM in Bangkok: what does it take? 11 Scaling up HIV treatment for MSM in Bangkok: what does it take? Methodology THE WORLD BANK GROUP Methodology Target population We specifically targeted MSM in metropolitan Bangkok. “Active MSM” is defined as “men who have had sex with other men in the past 12 months.” This study does not distinguish subgroups of MSM, such as transgender, male sex workers, and MSM with other specific risky sexual behaviors. We also assumed that MSM who utilized health facilities have similar HIV infection risk to and are “well-mixed” with those otherwise. Data collation and synthesis We collected the required epidemiological, service load, and capacity and costing data for HIV testing and ART services in Bangkok facilities. The main data sources include an extensive literature review on published and grey literature, database provided by the NHSO Thailand, capacity assessment survey in NHSO-listed medical facilities, and an empirical study on HIV testing and ART cost breakdown in 13 Bangkok medical facilities. Epidemiological data Epidemiological indicators, including population size estimates of MSM, characteristics of the HIV epidemic (e.g., HIV prevalence, annual HIV diagnoses, number of people on ART), risk behaviors of MSM (e.g., number of sexual partners and level of condom usage in sexual acts) were synthesized based on a systematic literature search for all available data in published articles, conference presentations and reports for Bangkok MSM over the period 2000-2012. Healthcare-seeking behaviors were reported by the NHSO database. The NHSO program provided free HIV testing twice a year for Thai citizens, regardless of health care insurance schemes they were registered for, through NHSO-registered HIV testing sites. For Thai PLHIV who use the NHSO scheme (around 80 percent of Thai PLHIV), NHSO also provides free antiretroviral treatment (ART), CD4 count twice a year (regardless of ART status), HIV viral load once a year, resistance testing when clinically indicated, and other key safety lab tests (for those on ART). NHSO-registered sites need to enter test results and clinical information into the NHSO electronic database in order to get cost reimbursement from NHSO. The number of Thai citizens who accessed HIV testing, number of those who tested HIV-positive, number of HIV-positive people who registered into the NHSO system for HIV treatment and care, number of HIV-positive people who started first-line and second-line ART regimens, CD4 count at entry into NHSO system, and the number of HIV-positive people who achieved undetectable HIV viral load after ART can be obtained by year of services from the database. Relevant data were synthesized to obtain best point estimates and uncertainty ranges for all the parameters used in later modelling evaluation. Mapping of MSM hotspots in Bangkok was obtained through previous mapping exercises shared by stakeholders, through an Internet survey via Adam’s Love website, and experts in the field. These hotspots are related to venues frequented by MSM in Bangkok. Venues mainly include saunas, spas, educational institutions, and department stores that are very well known to MSM. In addition, based on the address information provided by the NHSO database, we estimated the distance from the facilities to the nearest MSM hotspot on Google Maps. Service load and capacity data We conducted a telephone/letter survey to assess service load and capacity in providing HIV testing and ART services in 91 NHSO-listed medical facilities across Bangkok in 2011. The survey has Scaling up HIV treatment for MSM in Bangkok: what does it take? 13  been intentionally designed to be concise, with specific questions on the following aspects: (1) type of facility; (2) capacity to provide HIV testing; (3) capacity to provide ART; (4) capacity to provide treatment of HIV-related opportunistic infections and co-infections; (5) capacity of HIV reporting and surveillance. The complete survey is listed in Table S1. For the following modelling and resource allocation exercise, we made the assumption that all spare capacities in these facilities may be prioritized to MSM. This is based on two observations. Firstly, HIV prevalence among FSW and PWID have declined from 11 percent and 44 percent in 2000 to 2.5 percent and 24 percent in 2010 in Thailand, whereas HIV prevalence among MSM increased from 17 percent in 2003 to 20 percent in 2010. Secondly, the population size of MSM (550,571) is triple the sum of FSW (123,530) and PWID (40,300) in Thailand, but the HIV testing rates are far lower (MSM: 29 percent versus FSW: 51 percent and PWID 41 percent) [13, 14]. Based on these two reasons, we argue that the scale-up of HIV programs among MSM has much greater urgency than in other at-risk population, in which slower scale-up may be justifiable. Costing data for service linkage and provision Costing data for service linkage were collected based on a survey of available activities that con- nect eligible MSM to appropriate HIV testing and ART services. This part of data collection was conducted mostly in collaboration with in-country collaborators and local NGOs that conduct the services. More detail description of the services was provided in Table S7 and S9. In brief, we identified three major recruitment methods of MSM to HIV testing services: (1) conventional community-based outreach via peer-educator; (2) mobile point-of-care (POC) night clinics provided by Thai Red Cross AIDS Research Center (TRCARC) and BMA health centers; (3) Adam’s Love websites with innovative follow-up technologies hosted by TRCARC. AIDS Projects Management Group was the organization that piloted the sole linkage program to facilitate diagnosed and eligible HIV+ MSM to connect to ART services. The linkage model has been named “case-management model” (Table S9). Based on internal reports and communication with the responsible organizations, for each of these linkage programs, we collected indicators on program spending (e.g., cost of implementation and operation) and program effects (e.g., the number of individuals connected to HIV services). Out of the 91 NHSO-listed medical facilities, 13 were specifically chosen to collect costing data on service provision. The 13 sites were selected based on the current high number of MSM who accessed HIV testing and/or ART services at these sites, along with potential capacity to increase the scale of the services in the future. Data collection was conducted by a team of data collectors trained by Thai Red Cross in conjunction with key personnel at each of the sites. Overarching data was collected per site, including the characteristics of the sites (e.g., type of site, opening hours), service capacity, service load in the past 12 months, and cost breakdown of service provision. The main categories for HIV testing provision included staffing costs, commodity costs, laboratory costs, and operational costs specifically for HIV testing, whereas the categories for ART provision were monitoring costs, treatment cost, adherence cost, and operational costs specifically for ART. Modelling methodology To assess HIV epidemic trends and project the cost-effectiveness of investment scenarios, We employed a mathematical model to assess HIV epidemic trends and project the cost-effectiveness of investment scenarios. The epidemiological model, known as Optima, uses best-practice HIV 14 THE WORLD BANK GROUP epidemic modelling techniques and incorporates biological transmission processes, infection progression and sexual mixing patterns and other high-risk behaviors (Figure S3); we refer the reader elsewhere for a description of the model [15]. Optima incorporates a model of HIV transmission and progression. The model uses a coupled system of ordinary differential equations to track the movement of people between health states (Figure S1). The overall population is partitioned by group and health state. The model distinguishes people who are undiagnosed, diagnosed, and on effective ART. Diagnosis of HIV-infected individuals occurs based on an HIV testing rate dependent on CD4 count and population type. Similarly, diagnosed individuals begin treatment at a CD4 count dependent rate. The model tracks those on successful first- or second-line treatment (who have an increasing CD4 count) and those with treatment failure. The model is calibrated to match HIV prevalence data, and the uptake of ART from 2000-2012. The UNPD goals require reducing the number of HIV-related deaths and new cases by 50 percent by 2022. We investigate three ART scale-up scenarios, which represent the achievement of universal ART coverage among Bangkok high-risk MSM by 2022, 2017, and 2015 respectively. For each of these scenarios, we employed an optimization routine to identify the most economical way to achieve these targets. The two key optimization indicators are the HIV testing rate (