Allocating HIV prevention funds in the United States: recommendations from an optimization model

Prioritisation processes for programme implementation and evaluation in public health: A scoping review

Background

Programme evaluation is an essential and systematic activity for improving public health programmes through useful, feasible, ethical, and accurate methods. Finite budgets require prioritisation of which programmes can be funded, first, for implementation, and second, evaluation. While criteria for programme funding have been discussed in the literature, a similar discussion around criteria for which programmes are to be evaluated is limited. We reviewed the criteria and frameworks used for prioritisation in public health more broadly, and those used in the prioritisation of programmes for evaluation. We also report on stakeholder involvement in prioritisation processes, and evidence on the use and utility of the frameworks or sets of criteria identified. Our review aims to inform discussion around which criteria and domains are best suited for the prioritisation of public health programmes for evaluation.

Methods

We reviewed the peer-reviewed literature through OVID MEDLINE (PubMed) on 11 March 2022. We also searched the grey literature through Google and across key websites including World Health Organization (WHO), US Centers for Disease Control and Prevention (CDC), European Centre for Disease Prevention and Control (ECDC), and the International Association of National Public Health Institutes (IANPHI) (14 March 2022). Articles were limited to those published between 2002 and March 2022, in English, French or German.

Results

We extracted over 300 unique criteria from 40 studies included in the analysis. These criteria were categorised into 16 high-level conceptual domains to allow synthesis of the findings. The domains most frequently considered in the studies were “burden of disease” (33 studies), “social considerations” (30 studies) and “health impacts of the intervention” (28 studies). We only identified one paper which proposed criteria for use in the prioritisation of public health programmes for evaluation. Few prioritisation frameworks had evidence of use outside of the setting in which they were developed, and there was limited assessment of their utility. The existing evidence suggested that prioritisation frameworks can be used successfully in budget allocation, and have been reported to make prioritisation more robust, systematic, transparent, and collaborative.

Conclusion

Our findings reflect the complexity of prioritisation in public health. Development of a framework for the prioritisation of programmes to be evaluated would fill an evidence gap, as would formal assessment of its utility. The process itself should be formal and transparent, with the aim of engaging a diverse group of stakeholders including patient/public representatives.

Optimal resource allocation in HIV self-testing secondary distribution among Chinese MSM: data-driven integer programming models

Human immunodeficiency virus self-testing (HIVST) is an innovative and effective strategy important to the expansion of HIV testing coverage. Several innovative implementations of HIVST have been developed and piloted among some HIV high-risk populations like men who have sex with men (MSM) to meet the global testing target. One innovative strategy is the secondary distribution of HIVST, in which individuals (defined as indexes) were given multiple testing kits for both self-use (i.e.self-testing) and distribution to other people in their MSM social network (defined as alters). Studies about secondary HIVST distribution have mainly concentrated on developing new intervention approaches to further increase the effectiveness of this relatively new strategy from the perspective of traditional public health discipline. There are many points of HIVST secondary distribution in which mathematical modelling can play an important role. In this study, we considered secondary HIVST kits distribution in a resource-constrained situation and proposed two data-driven integer linear programming models to maximize the overall economic benefits of secondary HIVST kits distribution based on our present implementation data from Chinese MSM. The objective function took expansion of normal alters and detection of positive and newly-tested 'alters' into account. Based on solutions from solvers, we developed greedy algorithms to find final solutions for our linear programming models. Results showed that our proposed data-driven approach could improve the total health economic benefit of HIVST secondary distribution. This article is part of the theme issue 'Data science approaches to infectious disease surveillance'.

Peer- and community-led responses to HIV: A scoping review

INTRODUCTION

In June 2021, United Nations (UN) Member States committed to ambitious targets for scaling up community-led responses by 2025 toward meeting the goals of ending the AIDS epidemic by 2030. These targets build on UN Member States 2016 commitments to ensure that 30% of HIV testing and treatment programmes are community-led by 2030. At its current pace, the world is not likely to meet these nor other global HIV targets, as evidenced by current epidemiologic trends. The COVID-19 pandemic threatens to further slow momentum made to date. The purpose of this paper is to review available evidence on the comparative advantages of community-led HIV responses that can better inform policy making towards getting the world back on track.

METHODS

We conducted a scoping review to gather available evidence on peer- and community-led HIV responses. Using UNAIDS' definition of 'community-led' and following PRISMA guidelines, we searched peer-reviewed literature published from January 1982 through September 2020. We limited our search to articles reporting findings from randomized controlled trials as well as from quasi-experimental, prospective, pre/post-test evaluation, and cross-sectional study designs. The overall goals of this scoping review were to gather available evidence on community-led responses and their impact on HIV outcomes, and to identify key concepts that can be used to quickly inform policy, practice, and research.

FINDINGS

Our initial search yielded 279 records. After screening for relevance and conducting cross-validation, 48 articles were selected. Most studies took place in the global south (n = 27) and a third (n = 17) involved youth. Sixty-five percent of articles (n = 31) described the comparative advantage of peer- and community-led direct services, e.g., prevention and education (n = 23) testing, care, and treatment programs (n = 8). We identified more than 40 beneficial outcomes linked to a range of peer- and community-led HIV activities. They include improved HIV-related knowledge, attitudes, intentions, self-efficacy, risk behaviours, risk appraisals, health literacy, adherence, and viral suppression. Ten studies reported improvements in HIV service access, quality, linkage, utilization, and retention resulting from peer- or community-led programs or initiatives. Three studies reported structural level changes, including positive influences on clinic wait times, treatment stockouts, service coverage, and exclusionary practices.

CONCLUSIONS AND RECOMMENDATIONS

Findings from our scoping review underscore the comparative advantage of peer- and community-led HIV responses. Specifically, the evidence from the published literature leads us to recommend, where possible, that prevention programs, especially those intended for people living with and disproportionately affected by HIV, be peer- and community-led. In addition, treatment services should strive to integrate specific peer- and community-led components informed by differentiated care models. Future research is needed and should focus on generating additional quantitative evidence on cost effectiveness and on the synergistic effects of bundling two or more peer- and community-led interventions.

The Potential Epidemiological Impact of Coronavirus Disease 2019 (COVID-19) on the Human Immunodeficiency Virus (HIV) Epidemic and the Cost-effectiveness of Linked, Opt-out HIV Testing: A Modeling Study in 6 US Cities

Background

Widespread viral and serological testing for SARS-CoV-2 may present a unique opportunity to also test for HIV infection. We estimated the potential impact of adding linked, opt-out HIV testing alongside SARS-CoV-2 testing on HIV incidence and the cost-effectiveness of this strategy in six US cities.

Methods

Using a previously-calibrated dynamic HIV transmission model, we constructed three sets of scenarios for each city: (1) sustained current levels of HIV-related treatment and prevention services (status quo); (2) temporary disruptions in health services and changes in sexual and injection risk behaviours at discrete levels between 0%-50%; and (3) linked HIV and SARS-CoV-2 testing offered to 10%-90% of the adult population in addition to scenario (2). We estimated cumulative HIV infections between 2020-2025 and incremental cost-effectiveness ratios of linked HIV testing over 20 years.

Results

In the absence of linked, opt-out HIV testing, we estimated a total of 16.5% decrease in HIV infections between 2020-2025 in the best-case scenario (50% reduction in risk behaviours and no service disruptions), and 9.0% increase in the worst-case scenario (no behavioural change and 50% reduction in service access). We estimated that HIV testing (offered at 10%-90% levels) could avert a total of 576-7,225 (1.6%-17.2%) new infections. The intervention would require an initial investment of $20.6M-$220.7M across cities; however, the intervention would ultimately result in savings in health care costs in each city.

Conclusions

A campaign in which HIV testing is linked with SARS-CoV-2 testing could substantially reduce HIV incidence and reduce direct and indirect health care costs attributable to HIV.

Allocating treatment resources for hepatitis C in the UK: a constrained optimization modelling approach

Background and objective: Although the treatment of chronic hepatitis C (CHC) has significantly evolved with the introduction of direct-acting antivirals, the treatment uptake rates have been low especially among marginalized groups in the UK, such as people who inject drug (PWID) and men who have sex with men (MSM). Cutting health inequality is a major focus of healthcare agencies. This study aims to identify the optimal allocation of treatment budget for chronic hepatitis CHC among populations and treatments in the UK so that liver-related mortality in patients with CHC is minimized, given the constraint of treatment budget and equity issue. Methods: A constrained optimization modelling of resource allocation for the treatment of CHC was developed in Excel from the perspective of the UK National Health System over a lifetime horizon. The model was designated with the objective function of minimizing liver-related deaths by varying the decision variables, representing the number of patients receiving each treatment (elbasvir-grazoprevir, ombitasvir-paritaprevir-ritonavir-dasabuvir, sofosbuvir-ledipasvir, and pegylated interferon-ribavirin) in each population (the general population, PWID, and MSM). Two main constraints were formulated including treatment budget and the issue of equity. The model was populated with UK local data applying linear programming and underwent internal and external validation. Scenario analyses were performed to assess the robustness of model results. Results: Within the constraints of no additional funding over original spending in status quo and the consideration of the issue of equity among populations, the optimal allocation from the constrained optimization modelling (treating 13,122 PWID, 160 MSM, and 904 general patients with ombitasvir-paritaprevir-ritonavir-dasabuvir) was found to treat 2,430 more patients (relative change: 20.7%) and avert 78 liver-related deaths (relative change: 0.3%) compared with the current allocation. The number of patients receiving treatment increased 4,928 (relative change: 60.1%) among PWID and 42 (relative change: 35.8%) among MSM. Conclusion: The current allocation of treatment budget for CHC is not optimal in the UK. More patients would be treated, and more liver-related deaths would be avoided using a new allocation from a constrained optimization modelling without incurring additional spending and considering the issue of equity.

Optimal Allocation of Societal HIV Prevention Resources to Reduce HIV Incidence in the United States

Objectives. To optimize combined public and private spending on HIV prevention to achieve maximum reductions in incidence.Methods. We used a national HIV model to estimate new infections from 2018 to 2027 in the United States. We estimated current spending on HIV screening, interventions that move persons with diagnosed HIV along the HIV care continuum, pre-exposure prophylaxis, and syringe services programs. We compared the current funding allocation with 2 optimal scenarios: (1) a limited-reach scenario with expanded efforts to serve eligible persons and (2) an ideal, unlimited-reach scenario in which all eligible persons could be served.Results. A continuation of the current allocation projects 331 000 new HIV cases over the next 10 years. The limited-reach scenario reduces that number by 69%, and the unlimited reach scenario by 94%. The most efficient funding allocations resulted in prompt diagnosis and sustained viral suppression through improved screening of high-risk persons and treatment adherence support for those infected.Conclusions. Optimal allocations of public and private funds for HIV prevention can achieve substantial reductions in new infections. Achieving reductions of more than 90% under current funding will require that virtually all infected receive sustained treatment.

Optimization Models for HIV/AIDS Resource Allocation: A Systematic Review

OBJECTIVE

This study reviews optimization models for human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) resource allocation.

METHODS

We searched 2 databases for peer-reviewed articles published from January 1985 through August 2019 that describe optimization models for resource allocation in HIV/AIDS. We included models that consider 2 or more competing HIV/AIDS interventions. We extracted data on selected characteristics and identified similarities and differences across models. We also assessed the quality of mathematical disease transmission models based on the best practices identified by a 2010 task force.

RESULTS

The final qualitative synthesis included 23 articles that used 14 unique optimization models. The articles shared several characteristics, including the use of dynamic transmission modeling to estimate health benefits and the inclusion of specific high-risk groups in the study population. The models explored similar HIV/AIDS interventions that span primary and secondary prevention and antiretroviral treatment. Most articles were focused on sub-Saharan African countries (57%) and the United States (39%). There was notable variation in the types of optimization objectives across the articles; the most common was minimizing HIV incidence or maximizing infections averted (87%). Articles that utilized mathematical modeling of HIV disease and transmission displayed variable quality.

CONCLUSIONS

This systematic review of the literature identified examples of optimization models that have been applied in different settings, many of which displayed similar features. There were similarities in objective functions across optimization models, but they did not align with global HIV/AIDS goals or targets. Future work should be applied in countries facing the largest declines in HIV/AIDS funding.

The impact of localized implementation: determining the cost-effectiveness of HIV prevention and care interventions across six United States cities

OBJECTIVE

Effective interventions to reduce the public health burden of HIV/AIDS can vary in their ability to deliver value at different levels of scale and in different epidemiological contexts. Our objective was to determine the cost-effectiveness of HIV treatment and prevention interventions implemented at previously documented scales of delivery in six US cities with diverse HIV microepidemics.

DESIGN

Dynamic HIV transmission model-based cost-effectiveness analysis.

METHODS

We identified and estimated previously documented scale of delivery and costs for 16 evidence-based interventions from the US CDC's Compendium of Evidence-Based Interventions and Best Practices for HIV Prevention. Using a model calibrated for Atlanta, Baltimore, Los Angeles, Miami, New York City and Seattle, we estimated averted HIV infections, quality-adjusted life years (QALY) gained and incremental cost-effectiveness ratios (healthcare perspective; 3% discount rate, 2018$US), for each intervention and city (10-year implementation) compared with the status quo over a 20-year time horizon.

RESULTS

Increased HIV testing was cost-saving or cost-effective across cities. Targeted preexposure prophylaxis for high-risk MSM was cost-saving in Miami and cost-effective in Atlanta ($6123/QALY), Baltimore ($18 333/QALY) and Los Angeles ($86 117/QALY). Interventions designed to improve antiretroviral therapy initiation provided greater value than other treatment engagement interventions. No single intervention was projected to reduce HIV incidence by more than 10.1% in any city.

CONCLUSION

Combination implementation strategies should be tailored to local epidemiological contexts to provide the most value. Complementary strategies addressing factors hindering access to HIV care will be necessary to meet targets for HIV elimination in the United States.

Incorporation of Social Determinants of Health in the Peer-Reviewed Literature: A Systematic Review of Articles Authored by the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention

OBJECTIVES

Social determinants of health (SDHs) are the complex, structural, and societal factors that are responsible for most health inequities. Since 2003, the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP) has researched how SDHs place communities at risk for communicable diseases and poor adolescent health. We described the frequency and types of SDHs discussed in articles authored by NCHHSTP.

METHODS

We used the MEDLINE/PubMed search engine to systematically review the frequency and type of SDHs that appeared in peer-reviewed publications available in PubMed from January 1, 2009, through December 31, 2014, with a NCHHSTP affiliation. We chose search terms to identify articles with a focus on the following SDH categories: income and employment, housing and homelessness, education and schooling, stigma or discrimination, social or community context, health and health care, and neighborhood or built environment. We classified articles based on the depth of topic coverage as "substantial" (ie, one of ≤3 foci of the article) or "minimal" (ie, one of ≥4 foci of the article).

RESULTS

Of 862 articles authored by NCHHSTP, 366 (42%) addressed the SDH factors of interest. Some articles addressed >1 SDH factor (366 articles appeared 568 times across the 7 categories examined), and we examined them for each category that they addressed. Most articles that addressed SDHs (449/568 articles; 79%) had a minimal SDH focus. SDH categories that were most represented in the literature were health and health care (190/568 articles; 33%) and education and schooling (118/568 articles; 21%).

CONCLUSIONS

This assessment serves as a baseline measurement of inclusion of SDH topics from NCHHSTP authors in the literature and creates a methodology that can be used in future assessments of this topic.

Economic and Policy Analytic Approaches to Inform the Acceleration of HIV Prevention in the United States: Future Directions for the Field

The fields of economic and policy analysis have long played a role in quantifying the burden of the HIV epidemic and informing how to best deploy interventions and policies aimed at maximizing HIV care and reducing transmission. Looking towards the ultimate goal of ending the AIDS epidemic, we describe five areas for further development and application towards HIV policies: (1) setting measurable objectives to create a vision and monitor progress, (2) taking a health and wellness approach to goal-setting, (3) using impact matrices to inform quantitative analysis to explicitly address health disparities, (4) conducting budget impact analyses to project annual program costs and benefits, and (5) advancing the public health systems and services research agenda.

From Theory to Practice: Implementation of a Resource Allocation Model in Health Departments

OBJECTIVE

To develop a resource allocation model to optimize health departments' Centers for Disease Control and Prevention (CDC)-funded HIV prevention budgets to prevent the most new cases of HIV infection and to evaluate the model's implementation in 4 health departments.

DESIGN, SETTINGS, AND PARTICIPANTS

We developed a linear programming model combined with a Bernoulli process model that allocated a fixed budget among HIV prevention interventions and risk subpopulations to maximize the number of new infections prevented. The model, which required epidemiologic, behavioral, budgetary, and programmatic data, was implemented in health departments in Philadelphia, Chicago, Alabama, and Nebraska.

MAIN OUTCOME MEASURES

The optimal allocation of funds, the site-specific cost per case of HIV infection prevented rankings by intervention, and the expected number of HIV cases prevented.

RESULTS

The model suggested allocating funds to HIV testing and continuum-of-care interventions in all 4 health departments. The most cost-effective intervention for all sites was HIV testing in nonclinical settings for men who have sex with men, and the least cost-effective interventions were behavioral interventions for HIV-negative persons. The pilot sites required 3 to 4 months of technical assistance to develop data inputs and generate and interpret the results. Although the sites found the model easy to use in providing quantitative evidence for allocating HIV prevention resources, they criticized the exclusion of structural interventions and the use of the model to allocate only CDC funds.

CONCLUSIONS

Resource allocation models have the potential to improve the allocation of limited HIV prevention resources and can be used as a decision-making guide for state and local health departments. Using such models may require substantial staff time and technical assistance. These model results emphasize the allocation of CDC funds toward testing and continuum-of-care interventions and populations at highest risk of HIV transmission.

Improving Linkage, Retention, and Reengagement in HIV Care in 12 Metropolitan Areas

The Centers for Disease Control and Prevention developed the Enhanced Comprehensive HIV Prevention Planning (ECHPP) project to support 12 health departments' improvement of their HIV prevention and care portfolios in response to new national guidelines. We systematically analyzed 3 years of progress reports to learn how grantees put into practice local intervention strategies intended to link people to, and keep them in, HIV care. All grantees initiated seven activities to support these strategies: (1) improve surveillance data systems, (2) revise staffing duties and infrastructures, (3) update policies and procedures, (4) establish or strengthen partnerships, (5) identify persons not in care, (6) train personnel, and (7) create ways to overcome obstacles to receiving care. Factors supporting ECHPP grantee successes were thorough planning, attention to detail, and strong collaboration among health department units, and between the health department and external stakeholders. Other jurisdictions may consider adopting similar strategies when planning and enhancing HIV linkage, retention, and reengagement efforts in their areas. ECHPP experiences, lessons learned, and best practices may be relevant when applying new public health policies that affect community and health care practices jurisdiction-wide.

Cost Analysis and Performance Assessment of Partner Services for Human Immunodeficiency Virus and Sexually Transmitted Diseases, New York State, 2014

OBJECTIVE

To estimate the programmatic costs of partner services for HIV, syphilis, gonorrhea, and chlamydial infection.

STUDY SETTING

New York State and local health departments conducting partner services activities in 2014.

STUDY DESIGN

A cost analysis estimated, from the state perspective, total program costs and cost per case assignment, patient interview, partner notification, and disease-specific key performance indicator.

DATA COLLECTION

Data came from contracts, a time study of staff effort, and statewide surveillance systems.

PRINCIPAL FINDINGS

Disease-specific costs per case assignment (mean: $580; range: $502-$1,111), patient interview ($703; $608-$1,609), partner notification ($1,169; $950-$1,936), and key performance indicator ($2,697; $1,666-$20,255) varied across diseases. Most costs (79 percent) were devoted to gonorrhea and chlamydial infection investigations.

CONCLUSIONS

Cost analysis complements cost-effectiveness analysis in evaluating program performance and guiding improvements.

Activity spaces of men who have sex with men: An initial exploration of geographic variation in locations of routine, potential sexual risk, and prevention behaviors

Theory and research on HIV and among men who have sex with men (MSM) have long suggested the importance of non-residential locations in defining structural exposures. Despite this, most studies within these fields define place as a residential context, neglecting the potential influence of non-residential locations on HIV-related outcomes. The concept of activity spaces, defined as a set of locations to which an individual is routinely exposed, represents one theoretical basis for addressing this potential imbalance. Using a one-time online survey to collect demographic, behavioral, and spatial data from MSM, this paper describes activity spaces and examines correlates of this spatial variation. We used latent class analysis to identify categories of activity spaces using spatial data on home, routine, potential sexual risk, and HIV prevention locations. We then assessed individual and area-level covariates for their associations with these categories. Classes were distinguished by the degree of spatial variation in routine and prevention behaviors (which were the same within each class) and in sexual risk behaviors (i.e., sex locations and locations of meeting sex partners). Partner type (e.g. casual or main) represented a key correlate of the activity space. In this early examination of activity spaces in an online sample of MSM, patterns of spatial behavior represent further evidence of significant spatial variation in locations of routine, potential HIV sexual risk, and HIV prevention behaviors among MSM. Although prevention behaviors tend to have similar geographic variation as routine behaviors, locations where men engage in potentially high-risk behaviors may be more spatially focused for some MSM than for others.

Shifting Resources and Focus to Meet the Goals of the National HIV/AIDS Strategy: The Enhanced Comprehensive HIV Prevention Planning Project, 2010-2013

In September 2010, CDC launched the Enhanced Comprehensive HIV Prevention Planning (ECHPP) project to shift HIV-related activities to meet goals of the 2010 National HIV/AIDS Strategy (NHAS). Twelve health departments in cities with high AIDS burden participated. These 12 grantees submitted plans detailing jurisdiction-level goals, strategies, and objectives for HIV prevention and care activities. We reviewed plans to identify themes in the planning process and initial implementation. Planning themes included data integration, broad engagement of partners, and resource allocation modeling. Implementation themes included organizational change, building partnerships, enhancing data use, developing protocols and policies, and providing training and technical assistance for new and expanded activities. Pilot programs also allowed grantees to assess the feasibility of large-scale implementation. These findings indicate that health departments in areas hardest hit by HIV are shifting their HIV prevention and care programs to increase local impact. Examples from ECHPP will be of interest to other health departments as they work toward meeting the NHAS goals.

Cost Effectiveness of HIV Prevention Interventions in the U.S

INTRODUCTION

The purpose of this study was to assess and compare the cost effectiveness of current HIV prevention interventions in the U.S. using a consistent, standardized methodology.

METHODS

The cost effectiveness of common and emerging HIV biomedical and behavioral prevention interventions as delivered to men who have sex with men, injection drug users, and sexually active heterosexuals was estimated. Data on program costs, intervention efficacy, risk behaviors, and per contact transmission probabilities were collected from peer-reviewed papers and health department reports. These data were combined with 2010 national HIV incidence and prevalence surveillance data in a Bernoulli process model to estimate the reduced annual risk of HIV transmission or acquisition associated with these interventions. The cost per prevented case of HIV and the cost per saved quality-adjusted life year were then calculated. Analyses were conducted between 2014 and 2015.

RESULTS

Interventions to diagnose HIV and provide ongoing care and treatment had the lowest cost per prevented case. Among interventions targeted at specific risk groups, interventions for men who have sex with men were the most cost effective. The least cost-effective interventions typically addressed people at risk of acquiring HIV rather than those at risk of transmitting the disease.

CONCLUSIONS

HIV prevention interventions targeted at high-risk populations, those associated with the care continuum, and those that reduce the transmission risk of HIV-infected people are typically the most cost effective. Decision makers can consider these results in planning an efficient allocation of HIV prevention resources.

Using High-Impact HIV Prevention to Achieve the National HIV/AIDS Strategic Goals in Miami-Dade County, Florida: A Case Study

: In response to the release of the National HIV/AIDS Strategy, the Centers for Disease Control and Prevention developed the "Enhanced Comprehensive HIV Prevention Planning" project, which provided support to health departments in 12 Metropolitan Statistical Areas with the highest AIDS prevalence to strengthen local HIV programs. We describe a case study of how 1 Metropolitan Statistical Area, Miami-Dade County, developed and implemented a locally tailored plan. Examples include actions to reinforce local partnerships and identify neighborhoods with highest unmet needs, an improved condom distribution system to assist local HIV care providers, collaboration with local stakeholders to establish a new walk-in center for transgender client needs, and overcoming incompatibilities in health department and Ryan White Program computer record systems to facilitate faster and more efficient patient services. These examples show how jurisdictions both within Florida and elsewhere can create low-cost and sustainable activities tailored to improve local HIV prevention needs.

Potential impact on HIV incidence of higher HIV testing rates and earlier antiretroviral therapy initiation in MSM

BACKGROUND

Increased rates of testing, with early antiretroviral therapy (ART) initiation, represent a key potential HIV-prevention approach. Currently, in MSM in the United Kingdom, it is estimated that 36% are diagnosed by 1 year from infection, and the ART initiation threshold is at CD4 cell count 350/μl. We investigated what would be required to reduce HIV incidence in MSM to below 1 per 1000 person-years (i.e. <535 new infections per year) by 2030, and whether this is likely to be cost-effective.

METHODS

A dynamic, individual-based simulation model was calibrated to multiple data sources on HIV in MSM in the United Kingdom. Outcomes were projected according to future alternative HIV testing and ART initiation scenarios to 2030, considering also potential changes in levels of condomless sex.

RESULTS

For ART use to result in an incidence of close to 1/1000 person-years requires the proportion of all HIV-positive MSM with viral suppression to increase from below 60% currently to 90%, assuming no rise in levels of condomless sex. Substantial increases in HIV testing, such that over 90% of men are diagnosed within a year of infection, would increase the proportion of HIV-positive men with viral suppression to 80%, and it would be 90%, if ART is initiated at diagnosis. The scenarios required for such a policy to be cost-effective are presented.

CONCLUSION

This analysis provides targets for the proportion of all HIV-positive MSM with viral suppression required to achieve substantial reductions in HIV incidence.

Behavioral Interventions to Reduce Sexual Risk Behavior in Adults with HIV/AIDS Receiving HIV Care: A Systematic Review

Regular interactions with people living with HIV/AIDS (PLWHA) who are receiving care provide caregivers opportunities to deliver interventions to reduce HIV-related risks. We conducted a systematic review of behavioral interventions for PLWHA (provided at individual level by caregivers at HIV care settings) to determine their efficacy in reducing sexual risk behavior. Conference websites and biomedical literature databases were searched for studies from 1981 to 2013. Randomized and quasi-randomized controlled trials (with standard-of-care control groups), considering at least one of a list of HIV-related behavioral or biological outcomes in PLWHA aged ≥18 receiving HIV care with at least 3-month follow-up were included. No language or publication status restrictions were set. Standardized search, data abstraction, and evaluation methods were used. Five randomized controlled trials were included in the review. We found limited evidence that sexual risk reduction interventions increase condom use consistency in HIV transmission risk acts, and reduce the number of (casual) sexual partners. We still believe that regular interactions between HIV care providers and PLWHA provide valuable opportunities for theory-based sexual risk reduction interventions to restrain the spread of HIV.

Engineering behaviour change in an epidemic: the epistemology of NIH-funded HIV prevention science

Social scientific and public health literature on National Institutes of Health-funded HIV behavioural prevention science often assumes that this body of work has a strong biomedical epistemological orientation. We explore this assumption by conducting a systematic content analysis of all NIH-funded HIV behavioural prevention grants for men who have sex with men between 1989 and 2012. We find that while intervention research strongly favours a biomedical orientation, research into the antecedents of HIV risk practices favours a sociological, interpretive and structural orientation. Thus, with respect to NIH-funded HIV prevention science, there exists a major disjunct in the guiding epistemological orientations of how scientists understand HIV risk, on the one hand, and how they engineer behaviour change in behavioural interventions, on the other. Building on the extant literature, we suggest that the cause of this disjunct is probably attributable not to an NIH-wide positivist orientation, but to the specific standards of evidence used to adjudicate HIV intervention grant awards, including randomised controlled trials and other quantitative measures of intervention efficacy.

The lifetime medical cost savings from preventing HIV in the United States

OBJECTIVE

Enhanced HIV prevention interventions, such as preexposure prophylaxis for high-risk individuals, require substantial investments. We sought to estimate the medical cost saved by averting 1 HIV infection in the United States.

METHODS

We estimated lifetime medical costs in persons with and without HIV to determine the cost saved by preventing 1 HIV infection. We used a computer simulation model of HIV disease and treatment (CEPAC) to project CD4 cell count, antiretroviral treatment status, and mortality after HIV infection. Annual medical cost estimates for HIV-infected persons, adjusted for age, sex, race/ethnicity, and transmission risk group, were from the HIV Research Network (range, $1854-$4545/mo) and for HIV-uninfected persons were from the Medical Expenditure Panel Survey (range, $73-$628/mo). Results are reported as lifetime medical costs from the US health system perspective discounted at 3% (2012 USD).

RESULTS

The estimated discounted lifetime cost for persons who become HIV infected at age 35 is $326,500 (60% for antiretroviral medications, 15% for other medications, 25% nondrug costs). For individuals who remain uninfected but at high risk for infection, the discounted lifetime cost estimate is $96,700. The medical cost saved by avoiding 1 HIV infection is $229,800. The cost saved would reach $338,400 if all HIV-infected individuals presented early and remained in care. Cost savings are higher taking into account secondary infections avoided and lower if HIV infections are temporarily delayed rather than permanently avoided.

CONCLUSIONS

The economic value of HIV prevention in the United States is substantial given the high cost of HIV disease treatment.

HIV epidemic control-a model for optimal allocation of prevention and treatment resources

With 33 million people living with human immunodeficiency virus (HIV) worldwide and 2.7 million new infections occurring annually, additional HIV prevention and treatment efforts are urgently needed. However, available resources for HIV control are limited and must be used efficiently to minimize the future spread of the epidemic. We develop a model to determine the appropriate resource allocation between expanded HIV prevention and treatment services. We create an epidemic model that incorporates multiple key populations with different transmission modes, as well as production functions that relate investment in prevention and treatment programs to changes in transmission and treatment rates. The goal is to allocate resources to minimize R 0, the reproductive rate of infection. We first develop a single-population model and determine the optimal resource allocation between HIV prevention and treatment. We extend the analysis to multiple independent populations, with resource allocation among interventions and populations. We then include the effects of HIV transmission between key populations. We apply our model to examine HIV epidemic control in two different settings, Uganda and Russia. As part of these applications, we develop a novel approach for estimating empirical HIV program production functions. Our study provides insights into the important question of resource allocation for a country's optimal response to its HIV epidemic and provides a practical approach for decision makers. Better decisions about allocating limited HIV resources can improve response to the epidemic and increase access to HIV prevention and treatment services for millions of people worldwide.

Persistent racial/ethnic disparities in AIDS diagnosis rates among people who inject drugs in U.S. metropolitan areas, 1993-2007

OBJECTIVES

We estimated race/ethnicity-specific incident AIDS diagnosis rates (IARs) among people who inject drugs (PWID) in U.S. metropolitan statistical areas (MSAs) over time to assess the change in disparities after highly active antiretroviral therapy (HAART) dissemination.

METHODS

We compared IARs and 95% confidence intervals (CIs) for black/African American and Hispanic/Latino PWID with those of white PWID in 93 of the most populous MSAs. We selected two three-year periods from the years immediately preceding HAART (1993-1995) and the years with the most recent available data (2005-2007). To maximize stability, we aggregated data across three-year periods, and we aggregated data for black/African American and Hispanic/Latino PWID for most comparisons with data for white PWID. We assessed disparities by comparing IAR 95% CIs for overlap.

RESULTS

IARs were significantly higher for black/African American and Hispanic/Latino PWID than for white PWID in 81% of MSAs in 1993-1995 and 77% of MSAs in 2005-2007. MSAs where disparities became non-significant over time were concentrated in the West. Significant differences were more frequent in comparisons between black/African American and white PWID (85% of MSAs in 1993-1995, 79% of MSAs in 2005-2007) than in comparisons between Hispanic/Latino and white PWID (53% of MSAs in 1993-1995, 56% of MSAs in 2005-2007). IARs declined modestly across racial/ethnic groups in most MSAs.

CONCLUSIONS

AIDS diagnosis rates continue to be substantially higher for black/African American and Hispanic/Latino PWID than for white PWID in most large MSAs. This finding suggests a need for increased targeting of prevention and treatment programs, as well as research on MSA-level conditions that may serve to maintain the disparities.

Averting HIV infections in New York City: a modeling approach estimating the future impact of additional behavioral and biomedical HIV prevention strategies

Background

New York City (NYC) remains an epicenter of the HIV epidemic in the United States. Given the variety of evidence-based HIV prevention strategies available and the significant resources required to implement each of them, comparative studies are needed to identify how to maximize the number of HIV cases prevented most economically.

Methods

A new model of HIV disease transmission was developed integrating information from a previously validated micro-simulation HIV disease progression model. Specification and parameterization of the model and its inputs, including the intervention portfolio, intervention effects and costs were conducted through a collaborative process between the academic modeling team and the NYC Department of Health and Mental Hygiene. The model projects the impact of different prevention strategies, or portfolios of prevention strategies, on the HIV epidemic in NYC.

Results

Ten unique interventions were able to provide a prevention benefit at an annual program cost of less than $360,000, the threshold for consideration as a cost-saving intervention (because of offsets by future HIV treatment costs averted). An optimized portfolio of these specific interventions could result in up to a 34% reduction in new HIV infections over the next 20 years. The cost-per-infection averted of the portfolio was estimated to be $106,378; the total cost was in excess of $2 billion (over the 20 year period, or approximately $100 million per year, on average). The cost-savings of prevented infections was estimated at more than $5 billion (or approximately $250 million per year, on average).

Conclusions

Optimal implementation of a portfolio of evidence-based interventions can have a substantial, favorable impact on the ongoing HIV epidemic in NYC and provide future cost-saving despite significant initial costs.

Estimating the impact of state budget cuts and redirection of prevention resources on the HIV epidemic in 59 California local health departments

BACKGROUND

In the wake of a national economic downturn, the state of California, in 2009-2010, implemented budget cuts that eliminated state funding of HIV prevention and testing. To mitigate the effect of these cuts remaining federal funds were redirected. This analysis estimates the impact of these budget cuts and reallocation of resources on HIV transmission and associated HIV treatment costs.

METHODS AND FINDINGS

We estimated the effect of the budget cuts and reallocation for California county health departments (excluding Los Angeles and San Francisco) on the number of individuals living with or at-risk for HIV who received HIV prevention services. We used a Bernoulli model to estimate the number of new infections that would occur each year as a result of the changes, and assigned lifetime treatment costs to those new infections. We explored the effect of redirecting federal funds to more cost-effective programs, as well as the potential effect of allocating funds proportionately by transmission category. We estimated that cutting HIV prevention resulted in 55 new infections that were associated with $20 million in lifetime treatment costs. The redirection of federal funds to more cost-effective programs averted 15 HIV infections. If HIV prevention funding were allocated proportionately to transmission categories, we estimated that HIV infections could be reduced below the number that occurred annually before the state budget cuts.

CONCLUSIONS

Reducing funding for HIV prevention may result in short-term savings at the expense of additional HIV infections and increased HIV treatment costs. Existing HIV prevention funds would likely have a greater impact on the epidemic if they were allocated to the more cost-effective programs and the populations most likely to acquire and transmit the infection.