Disease Intervention Specialist-Delivered Interventions and Other Partner Services for HIV and Sexually Transmitted Infections: A Systematic Review.

INTRODUCTION: Disease intervention specialists (DIS) are critical for delivering partner services programs that provide partner notification, counseling, referral, and other services for HIV, sexually transmitted infections (STIs), and other infections. This systematic review of partner services and other DIS-delivered interventions for HIV and STIs was conducted to summarize the effectiveness of these programs and identify evidence gaps. METHODS: A systematic literature review was conducted with a narrative synthesis. Articles were located using keyword searches in MEDLINE, Web of Science, CINAHL, and ProQuest through December 2022 and analyzed in 2023-2024. Included studies addressed an intervention of partner services or other DIS-delivered services for HIV or STIs; a United States setting; primary data collection; and an external comparison group or pre-post design. RESULTS: A total of 1,915 unique records were screened for eligibility, with 30 studies included. Overall, DIS-delivered interventions improved clinical outcomes among index patients and population outcomes. Many studies focused on program process measures rather than population-level epidemiologic outcomes. All but one studies were scored as having low or medium strength of evidence. CONCLUSIONS: The evidence could be strengthened by establishing a streamlined set of core metrics, assessing impact using rigorous causal inference methodologies, linking program and clinical data systems, and supplementing impact evaluations with evidence on implementation strategies.

The Testing Imperative: Why the US Ending the Human Immunodeficiency Virus (HIV) Epidemic Program Needs to Renew Efforts to Expand HIV Testing in Clinical and Community-Based Settings.

Data from several modeling studies demonstrate that large-scale increases in human immunodeficiency virus (HIV) testing across settings with a high burden of HIV may produce the largest incidence reductions to support the US Ending the HIV Epidemic (EHE) initiative's goal of reducing new HIV infections 90% by 2030. Despite US Centers for Disease Control and Prevention's recommendations for routine HIV screening within clinical settings and at least yearly screening for individuals most at risk of acquiring HIV, fewer than half of US adults report ever receiving an HIV test. Furthermore, total domestic funding for HIV prevention has remained unchanged between 2013 and 2019. The authors describe the evidence supporting the value of expanded HIV testing, identify challenges in implementation, and present recommendations to address these barriers through approaches at local and federal levels to reach EHE targets.

Sexual Practice Changes Post-HIV Diagnosis Among Men Who Have Sex with Men in the United States: A Systematic Review and Meta-analysis.

Men who have sex with men (MSM) often change sexual behaviors following HIV diagnosis. This systematic review examined such changes, including sero-adaptive behaviors (i.e., deliberate safer-sex practices to reduce transmission risk) to better understand the magnitude of their association with HIV diagnosis. We searched four databases (1996-2017) and reviewed references from other systematic reviews. We included studies conducted in the United States that compared sexual behavior among HIV-infected "aware" versus "unaware" MSM. We meta-analytically pooled RRs and associated 95% confidence intervals (CI) using random-effects models, and assessed risk of bias and evidence quality. Twenty studies reported k = 131 effect sizes on sexual practices outcomes, most of which reported changes in unprotected sex (k = 85), and on sex with at-risk partners (k = 76); 11 reported sero-adaptive behaviors. Unprotected anal intercourse with an HIV-uninfected/unknown-status partner was less likely among aware MSM (insertive position: k = 2, RR 0.26, 95% CI 0.17, 0.41; receptive position: k = 2, RR 0.53, 95% CI 0.37, 0.77). Risk of not always serosorting among aware MSM (k = 3) was RR = 0.92 (0.83, 1.02). Existing evidence, although low-quality, suggests that HIV-infected MSM tend to adopt safer sexual practices once aware of their diagnosis. Variation in reporting of outcomes limits their comparability. Sero-adaptive behavior data are sparse.

Costs and Consequences of Eliminating a Routine, Point-Of-Care HIV Screening Program in a High-Prevalence Jail.

INTRODUCTION: This study aims to assess the public health impact of eliminating a longstanding routine HIV screening program and replacing it with targeted testing. In addition, costs, outcomes, and cost effectiveness of routine screening are compared with those of targeted testing in the Fulton County Jail, Atlanta, Georgia. METHODS: A published mathematical model was used to assess the cost effectiveness and public health impact of routine screening (March 2013-February 2014) compared with those of targeted testing (January 2018-December 2018) from a health system perspective. Costs, outcomes, and other model inputs were derived from the testing programs and the published literature, and the cost effectiveness analysis was conducted from 2019 to 2020. RESULTS: Routine screening identified 74 more new HIV infections over 1 year than targeted testing, resulting in an estimated 10 HIV transmissions averted and 45 quality-adjusted life-years saved, and was cost saving. The missed opportunity to diagnose infections because routine screening was eliminated resulted in an estimated 8.4 additional HIV transmissions and $3.7 million in additional costs to the healthcare system. CONCLUSIONS: Routine HIV screening in high-prevalence jails is cost effective and has a larger impact on public health than targeted testing. Prioritizing sustained funding for routine, jail-based HIV screening programs in high-prevalence areas may be important to realizing the national HIV prevention goals.

Change in Condom Use in Populations Newly Aware of HIV Diagnosis in the United States and Canada: A Systematic Review and Meta-Analysis.

HIV-infected individuals "aware" of their infection are more likely to use condoms, compared to HIV-infected "unaware" persons. To quantify this likelihood, we undertook a systematic review and meta-analysis of U.S. and Canadian studies. Twenty-one eligible studies included men who have sex with men (MSM; k = 15), persons who inject drugs (PWID; k = 2), and mixed populations of high-risk heterosexuals (HRH; k = 4). Risk ratios (RR) of "not always using condoms" with partners of any serostatus were lower among aware MSM (RR 0.44 [not significant]), PWID (RR 0.70) and HRH (RR 0.27); and, in aware MSM, with partners of HIV-uninfected or unknown status (RR 0.46). Aware individuals had lower "condomless sex likelihood" with HIV-uninfected or unknown status partners (MSM: RR 0.58; male PWID: RR 0.44; female PWID: RR 0.65; HRH: RR 0.35) and with partners of any serostatus (MSM only, RR 0.72). The association diminished over time. High risk of bias compromised evidence quality.

Health Utility Estimates and Their Application to HIV Prevention in the United States: Implications for Cost-Effectiveness Modeling and Future Research Needs.

Objectives. Health utility estimates from the current era of HIV treatment, critical for cost-effectiveness analyses (CEA) informing HIV health policy, are limited. We examined peer-reviewed literature to assess the appropriateness of commonly referenced utilities, present previously unreported quality-of-life data from two studies, and discuss future implications for HIV-related CEA. Methods. We searched a database of cost-effectiveness analyses specific to HIV prevention efforts from 1999 to 2016 to identify the most commonly referenced sources for health utilities and to examine practices around using and reporting health utility data. Additionally, we present new utility estimates from the Centers of Disease Control and Prevention's Medical Monitoring Project (MMP) and the INSIGHT Strategies for Management of Anti-Retroviral Therapy (SMART) trial. We compare data collection time frames, sample characteristics, assessment methods, and key estimates. Results. Data collection for the most frequently cited utility estimates ranged from 1985 to 1997, predating modern HIV treatment. Reporting practices around utility weights are poor and lack details on participant characteristics, which may be important stratifying factors for CEA. More recent utility estimates derived from MMP and SMART were similar across CD4+ count strata and had a narrower range than pre-antiretroviral therapy (ART) utilities. Conclusions. Despite the widespread use of ART, cost-effectiveness analysis of HIV prevention interventions frequently apply pre-ART health utility weights. Use of utility weights reflecting the current state of the US epidemic are needed to best inform HIV research and public policy decisions. Improved practices around the selection, application, and reporting of health utility data used in HIV prevention CEA are needed to improve transparency.

Effectiveness of community-based condom distribution interventions to prevent HIV in the United States: A systematic review and meta-analysis.

BACKGROUND: Despite significant public health implications, the extent to which community-based condom distribution interventions (CDI) prevent HIV infection in the United States is not well understood. METHODS: We systematically reviewed research evidence applying Cochrane Collaboration methods. We used a comprehensive search strategy to search multiple bibliographic databases for relevant randomized controlled trials (RCTs) and non-RCTs published from 1986-2017. We focused on CDI that made condoms widely available or accessible in community settings. Eligible outcomes were HIV infection (primary), sexually transmitted infections, condom use, and multiple sexual partnership. Two reviewers independently screened citations to assess their eligibility, extracted study data, and assessed risk of bias. We calculated risk ratios (RR) with 95% confidence intervals (CI) and pooled them using random-effects models. We assessed evidence quality using GRADE. RESULTS: We reviewed 5,110 unique records. Nine studies (including one RCT) met eligibility criteria. Studies were conducted in 10 US states between 1989 and 2011. All studies were at high risk of bias. Interventions were categorized into three groups: "Ongoing" (unlimited access to condoms), "Ongoing-plus" (unlimited access to condoms, with co-interventions), and "Coupon-based" (coupons redeemed for condoms). No studies reported incident HIV. Ongoing CDI (four non-RCTs) modestly reduced condomless sex (RR 0.88, 95% CI 0.78 to 0.99). Ongoing-plus CDI (two non-RCTs) significantly reduced multiple sexual partnership (RR 0.37, 95% CI 0.16 to 0.87). Of two coupon-based studies, one (non-RCT) showed reduction in condomless sex in female participants (Odds Ratio 0.67, 95% CI 0.47 to 0.96), while the other one (RCT) showed no effect on STI incidence (RR 0.91, 95% CI 0.63 to 1.31). Evidence quality was "very low" for all outcomes. CONCLUSIONS: CDI may reduce some risky sexual behaviors, but the evidence for any reduction is limited and of low-quality. Lack of biological outcomes precludes assessing the link between CDI and HIV incidence.

Recommendations for HIV Screening of Gay, Bisexual, and Other Men Who Have Sex with Men - United States, 2017.

CDC's 2006 recommendations for human immunodeficiency virus (HIV) testing state that all persons aged 13-64 years should be screened for HIV at least once, and that persons at higher risk for HIV infection, including sexually active gay, bisexual, and other men who have sex with men (MSM), should be rescreened at least annually (1). Authors of reports published since 2006, including CDC (2), suggested that MSM, a group that is at highest risk for HIV infection, might benefit from being screened more frequently than once each year. In 2013, the U.S. Preventive Services Task Force (USPSTF) found insufficient evidence to specify an HIV rescreening interval but recommended annual screening for MSM as a reasonable approach (3). However, some HIV providers have begun to offer more frequent screening, such as once every 3 or 6 months, to some MSM. A CDC work group conducted a systematic literature review and held four expert consultations to review programmatic experience to determine whether there was sufficient evidence to change the 2006 CDC recommendation (i.e., at least annual HIV screening of MSM in clinical settings). The CDC work group concluded that the evidence remains insufficient to recommend screening more frequently than at least once each year. CDC continues to recommend that clinicians screen asymptomatic sexually active MSM at least annually. Each clinician can consider the benefits of offering more frequent screening (e.g., once every 3 or 6 months) to individual MSM at increased risk for acquiring HIV infection, weighing their patients' individual risk factors, local HIV epidemiology, and local testing policies.

Acute infections, cost and time to reporting of HIV test results in three U.S. State Public Health Laboratories.

OBJECTIVE: In three U.S. State Public Health Laboratories (PHLs) using a fourth-generation immunoassay (IA), an HIV-1/HIV-2 differentiation antibody IA and a nucleic acid test (NAT), we characterized the yield and time to reporting of acute infections, and cost per positive specimen. METHODS: Routine HIV testing data were collected from July 1, 2012-June 30, 2013 for Massachusetts and Maryland PHLs, and from November 27, 2012-June 30, 2013 for Michigan PHL. Massachusetts and Michigan used fourth-generation and differentiation IAs with NAT conducted by a referral laboratory. In Maryland, fourth-generation IA repeatedly reactive specimens were followed by a Western blot (WB), and those with negative or indeterminate results were tested with a differentiation IA and HIV-1 NAT, and if positive by NAT, confirmed by a different HIV-1 NAT. Specimens from WB-positive persons at risk for HIV-2 were tested with a differentiation IA and, if positive, with an HIV-2 WB and/or differential HIV-1/HIV-2 proviral DNA polymerase chain reaction. RESULTS: Among 7914 specimens from Massachusetts PHL, 6069 from Michigan PHL, and 36,266 from Maryland PHL, 0.10%, 0.02% and 0.05% acute infections were identified, respectively. Massachusetts and Maryland PHLs each had 1 HIV-2 positive specimen. The median time from specimen receipt to laboratory reporting of results for acute infections at Massachusetts, Michigan and Maryland PHLs was 8, 11, and 7 days respectively. The laboratory cost per HIV positive specimen was $336 (Massachusetts), $263 (Michigan) and $210 (Maryland). CONCLUSIONS: Acute and established infections were found by PHLs using fourth-generation IA in conjunction with antibody tests and NAT. Time to reporting of acute HIV test results to clients was suboptimal, and needs to be streamlined to expedite treatment and interrupt transmission.

Acute Infections, Cost per Infection and Turnaround Time in Three United States Hospital Laboratories Using Fourth-Generation Antigen-Antibody Human Immunodeficiency Virus Immunoassays.

Background. To improve clinical and public health outcomes through early human immunodeficiency virus (HIV) detection, fourth-generation antigen/antibody immunoassay (4IA) and supplemental testing results must be returned rapidly. Methods. We examined HIV testing data at Harborview Medical Center (HMC), Massachusetts General Hospital (MGH), and the Medical University of South Carolina (MUSC), which used 4IA and supplemental antibody and nucleic acid tests (NATs). At MGH and MUSC, HIV-1 Western blot (WB) and HIV-2 testing were conducted at a reference laboratory. We compared time from specimen collection to laboratory result for established (positive WB) and acute infections (reactive 4IA, negative/indeterminate WB, detectable NAT), and we calculated testing cost per positive-test result. Results. From 3731 (MUSC) to 19 774 (MGH) tests were conducted; 0.01% (MGH) to 0.05% (HMC) were acute infections. Each laboratory had reactive 4IA, WB-negative, or indeterminate specimens without NAT (ie, potential acute infections). Time to result was 1.5 (HMC) to 5.2 days (MGH) for acute and 1.0 (HMC) to 5.2 days (MGH) for established infections. Costs were $1054 (MGH) to $1521 (MUSC). Conclusions. Conducting supplemental testing in-house lowered turnaround times, which may be further reduced with rapid HIV-1/HIV-2 differentiation tests. Hospitals may benefit from quantitative NATs not requiring physician orders, so all potential acute infections receive NAT.

Cost-Effectiveness of Frequent HIV Testing of High-Risk Populations in the United States.

PURPOSE: Data showing a high incidence of HIV infection among men who have sex with men (MSM) who had annual testing suggest that more frequent HIV testing may be warranted. Testing technology is also a consideration given the availability of sensitive testing modalities and the increased use of less-sensitive rapid, point-of-care antibody tests. We assessed the cost-effectiveness of HIV testing of MSM and injection drug users (IDUs) at 3- and 6-month intervals using fourth-generation and rapid tests. METHODS: We used a published mathematical model of HIV transmission to evaluate testing intervals for each population using cohorts of 10,000 MSM and IDU. We incorporated HIV transmissions averted due to serostatus awareness and viral suppression. We included costs for HIV testing and treatment initiation, and also treatment costs saved from averted transmissions. RESULTS: For MSM, HIV testing was cost saving or cost effective over a 1-year period for both 6-month compared with annual testing and quarterly compared with 6-month testing using either test. Testing IDU every 6 months compared with annually was moderately cost effective over a 1-year period with a fourth-generation test, while testing with rapid, point-of-care tests or quarterly was not cost effective. MSM results remained robust in sensitivity analysis, whereas IDU results were sensitive to changes in HIV incidence and continuum-of-care parameters. Threshold analyses on costs suggested that additional implementation costs could be incurred for more frequent testing for MSM while remaining cost effective. CONCLUSIONS: HIV testing of MSM as frequently as quarterly is cost effective compared with annual testing, but testing IDU more frequently than annually is generally not cost effective.

Notification following new positive HIV test results.

Client notification of a new HIV diagnosis is critical for timely access to treatment and reduction in behaviours associated with HIV infection. It is also an important input in HIV transmission and disease progression models. We used national, Centers for Disease Control and Prevention-funded HIV testing events data collected through the National HIV Prevention Program Monitoring and Evaluation system to update estimates of the proportion of newly identified HIV-positives notified of their status. We compared estimates from 2008 to 2010 across test technologies, settings, and HIV risk groups. In 2010, notification following a positive rapid test was 99.6% compared with 99.3% in 2008. Notification following a positive conventional test was 81.5% in 2010 compared with 80.8% in 2008. To realise the full promise of early HIV diagnosis and treatment for the prevention of additional HIV cases, efforts to ensure prompt notification following a new HIV diagnosis will be crucial.

Nearly Half Of US Adults Living With HIV Received Federal Disability Benefits In 2009.

The effects of HIV infection on national labor-force participation have not been rigorously evaluated. Using data from the Medical Monitoring Project and the National Health Interview Survey, we present nationally representative estimates of the receipt of disability benefits by adults living with HIV receiving care compared with the general US adult population. We found that in 2009, adults living with HIV were nine times more likely than adults in the general population to receive disability benefits. The risk of being on disability is also greater for younger and more educated adults living with HIV compared to the general population, which suggests that productivity losses can result from HIV infection. To prevent disability, early diagnosis and treatment of HIV are essential. This study offers a baseline against which to measure the impacts of recently proposed or enacted changes to Medicaid and private insurance markets, including the Affordable Care Act and proposed revisions to the Social Security Administration's HIV Infection Listings.

A systematic review on cost effectiveness of HIV prevention interventions in the United States.

BACKGROUND: The Centers for Disease Control and Prevention (CDC) focus on funding HIV prevention interventions likely to have high impact on the HIV epidemic. In its most recent funding announcement to state and local health department grantees, CDC required that health departments allocate the majority of funds to four HIV prevention interventions: HIV testing, prevention with HIV-positives and their partners, condom distribution and policy initiatives. OBJECTIVE: We conducted a systematic review of the published literature to determine the extent of the cost-effectiveness evidence for each of those interventions. METHODOLOGY: We searched for US-based studies published through October 2012. The studies that qualified for inclusion contained original analyses that reported costs per quality-adjusted life-year saved, life-year saved, HIV infection averted, or new HIV diagnosis. For each study, paired reviewers performed a detailed review and data extraction. We reported the number of studies related to each intervention and summarized key cost-effectiveness findings according to intervention type. Costs were converted to 2011 US dollars. RESULTS: Of the 50 articles that met the inclusion criteria, 33 related to HIV testing, 15 assessed prevention with HIV-positives and partners, three reported on condom distribution, and one reported on policy initiatives. Methodologies and cost-effectiveness metrics varied across studies and interventions, making them difficult to compare. CONCLUSION: Our review provides an updated summary of the published evidence of cost effectiveness of four key HIV prevention interventions recommended by CDC. With the exception of testing-related interventions, including partner services, where economic evaluations suggest that testing often can be cost effective, more cost-effectiveness research is needed to help guide the most efficient use of HIV prevention funds.

Costs and outcomes of laboratory diagnostic algorithms for the detection of HIV.

BACKGROUND: An alternative HIV testing algorithm, designed to improve the detection of acute and early infections and differentiate between HIV-1 and HIV-2 antibodies, has been developed by the Centers for Disease Control and Prevention and the Association of Public Health Laboratories. While it promises greater sensitivity, it also raises concerns about costs. OBJECTIVE: We sought to compare the most commonly used algorithm which was developed in 1989, a third-generation (3G) immunoassay (IA) and Western blot confirmatory test, to a newer algorithm. The new algorithm includes either a 3G or a fourth-generation (4G) initial IA, followed by confirmatory testing with a HIV-1/HIV-2 differentiation IA and, if needed, a nucleic acid amplification test (NAT). STUDY DESIGN: We conducted an analysis of HIV testing costs from the perspective of the laboratory, and classified costs according to IA testing volume. We developed a decision analytic model, populated with cost data from 17 laboratories and published assay performance data, to compare the cost-effectiveness of the testing algorithms for a cohort of 30,000 specimens with a 1% HIV prevalence and 0.1% acute HIV infection prevalence. RESULTS: Costs were lower in high-volume laboratories regardless of testing algorithm. For specimens confirmed positive for HIV antibody, the alternative algorithm (IA, Multispot) was less costly than the current algorithm (IA, WB); however, there was wide variation in reported testing costs. For our cohort, the alternative algorithm initiated with a 3G IA and 4G IA identified 15 and 25 more HIV infections, respectively, than the 1989 algorithm. In medium-volume laboratories, the 1989 algorithm was more costly and less effective than the alternative algorithm with a 3G IA; in high-volume laboratories, the alternative algorithm with 3G IA costs $162 more per infection detected. The alternative algorithm with 4G instead of 3G incurred an additional cost of $14,400 and $4865 in medium- and high-volume labs, respectively. DISCUSSION: HIV testing costs varied with IA testing volumes. The additional cost of 4G over 3G IA might be justified by the additional cases of HIV detected and transmissions averted due to earlier detection. CONCLUSION: The alternative HIV testing algorithm compares favorably to the 1989 algorithm in terms of cost and effectiveness.

Updates of lifetime costs of care and quality-of-life estimates for HIV-infected persons in the United States: late versus early diagnosis and entry into care.

BACKGROUND: Lifetime costs of care and quality-of-life estimates for HIV-infected persons depend on the disease stage at which these persons are diagnosed, enter care, and start antiretroviral therapy. Updated estimates were used to analyze the effects of late versus early diagnosis/entry on US lifetime care costs, quality-of-life estimates, and HIV transmissions. METHODS: The Progression and Transmission of HIV/AIDS model was used to estimate discounted (3%) lifetime treatment costs ($US 2011) and quality-of-life variables from time of infection for cohorts of 10,000 HIV-infected index patients in 4 categories of CD4 count at diagnosis: (I) ≤200 cells/µL, (II) 201-350 cells/µL, (III) 351-500 cells/µL, and (IV) 501-900 cells/µL. It is assumed that index patient diagnoses were uniformly distributed across the CD4 count range in each category and that patients entered care at the time of diagnosis, remained in care, and were eligible to initiate antiretroviral therapy at a CD4 count of 500 cells/µL. Lifetime transmissions of the index patients were also estimated. RESULTS: Discounted average lifetime costs varied from $253,000 for category I index patients to $402,000 for category IV patients. Discounted quality-adjusted life years lost decreased from 7.95 to 4.45 across these categories, additional years of life expectancy increased from 30.8 to 38.1, and lifetime transmissions decreased from 1.40 to 0.72. CONCLUSIONS: Early diagnosis and treatment of HIV infection increases lifetime costs but improves length and quality of life and reduces the number of new infections transmitted by nearly 50%.

Cost effectiveness of the National HIV/AIDS Strategy goal of increasing linkage to care for HIV-infected persons.

BACKGROUND: One of the goals of the National HIV/AIDS Strategy (NHAS) is to increase the proportion of HIV-infected individuals linked to care within 3 months of diagnosis (early linkage) from 65% to 85%. Earlier access to care, and eventually, to treatment, increases life expectancy and quality of life for HIV-infected persons. However, longer treatment is also associated with higher costs, especially for antiretroviral drugs. We evaluated the cost effectiveness of achieving the NHAS goal and estimated the maximum cost that HIV programs could spend on linkage to care and remain cost effective. METHODS: We used the Progression and Transmission of HIV/AIDS model to estimate the effects on life measures and costs associated with increasing early linkage to care from 65% to 85%. We estimated an incremental cost-effectiveness ratio as the additional cost required to reach the target divided by the quality-adjusted life years (QALYs) gained and assumed that programs costing $100,000 or less per QALY gained are cost effective. RESULTS: Achieving the NHAS linkage-to-care goal increased life expectancy by 0.4 years and delayed the onset of AIDS by 1.2 years on average for every HIV-diagnosed person. Increasing early linkage to care cost an extra $62,200 per QALY gained, considering only benefits to index persons. The maximum that could be cost effectively spent on early linkage-to-care interventions was approximately $5100 per HIV-diagnosed person. CONCLUSIONS: Considerable investment can be cost effectively made to achieve the NHAS goal on early linkage to care.

How much should we pay for a new HIV diagnosis? A mathematical model of HIV screening in US clinical settings.

OBJECTIVE: To develop a model to assist clinical setting decision makers in determining how much they can spend on human immunodeficiency virus (HIV) screening and still be cost-effective. DESIGN: The authors developed a simple mathematical model relating the program cost per new HIV diagnosis to the cost per HIV infection averted and the cost per quality-adjusted life year (QALY) saved by screening. They estimated outcomes based on behavioral changes associated with awareness of HIV infection and applied the model to US sexually transmitted disease clinics. METHODS: The authors based the cost per new HIV diagnosis (2009 US dollars) on the costs of testing and the proportion of persons who tested positive. Infections averted were calculated from the reduction in annual transmission rates between persons aware and unaware of their infections. The authors defined program costs from the sexually transmitted disease clinic perspective and treatment costs and QALYs saved from the societal perspective. They undertook numerous sensitivity analyses to determine the robustness of the base case results. RESULTS: In the base case, the cost per new HIV diagnosis was $2528, the cost per infection averted was $40,516, and the cost per QALY saved was less than zero, or cost-saving. Given the model inputs, the cost per new diagnosis could increase to $22,909 to reach the cost-saving threshold and to $63,053 for the cost-effectiveness threshold. All sensitivity analyses showed that the cost-effectiveness results were consistent for extensive variation in the values of model inputs. CONCLUSIONS: HIV screening in a clinical setting is cost-effective for a wide range of testing costs, variations in positivity rates, reductions in HIV transmissions, and variation in the receipt of test results.

Return on public health investment: CDC's Expanded HIV Testing Initiative.

BACKGROUND: Over a 3-year period, the Centers for Disease Control and Prevention invested $102.3 million in a large-scale HIV testing program, the Expanded HIV Testing Initiative for populations disproportionally affected by HIV. Policy makers, who must optimize public health given a set budget, are interested in the financial return on investment (ROI) of large-scale HIV testing. METHODS: We conducted an ROI analysis using expenditure and outcome data from the program. A health system perspective was used that included all program expenditures including medical costs of treating newly diagnosed patients. We incorporated benefits of HIV transmissions averted from persons diagnosed of their infection through the Initiative compared with when, on average, those persons would have been diagnosed without the Initiative (3 years later in the base case). HIV transmissions were derived from a published mathematical model of HIV transmission. In sensitivity analysis, we tested the effect of 1-year to 5-year alternate testing intervals and differences in the prevalence of undiagnosed HIV infection. RESULTS: Under the Initiative, 2.7 million persons were tested for HIV, there was a newly diagnosed HIV positivity rate of 0.7%, and an estimated 3381 HIV infections were averted. It achieved a return of $1.95 for every dollar invested. ROI ranged from $1.46 to $2.01 for alternative testing intervals of 1-5 years and remained above $1 (positive return on investment) with a prevalence of undiagnosed HIV infection as low as 0.12%. CONCLUSIONS: The expanded testing Initiative yielded ROI values of >$1 under a broad range of sensitivity analyses and provides further support for large-scale HIV testing programs.