The clinical impact and cost-effectiveness of routine, voluntary HIV screening in South Africa

Virological, serological and clinical outcomes in chronic hepatitis B virus infection: development and validation of the HEPA-B simulation model

OBJECTIVES

Detailed simulation models are needed to assess strategies for prevention and treatment of hepatitis B virus (HBV) infection, the world's leading cause of liver disease. We sought to develop and validate a simulation model of chronic HBV that incorporates virological, serological and clinical outcomes.

METHODS

We developed a novel Monte Carlo simulation model (the HEPA-B Model) detailing the natural history of chronic HBV. We parameterised the model with epidemiological data from the Western Pacific and sub-Saharan Africa. We simulated the evolution of HBV DNA, 'e' antigen (HBeAg) and surface antigen (HBsAg). We projected incidence of HBeAg loss, HBsAg loss, cirrhosis, hepatocellular carcinoma (HCC) and death over 10-year and lifetime horizons. We stratified outcomes by five HBV DNA categories at the time of HBeAg loss, ranging from HBV DNA<300 copies/mL to >106 copies/mL. We tested goodness of fit using intraclass coefficients (ICC).

RESULTS

Model-projected incidence of HBeAg loss was 5.18% per year over lifetime (ICC, 0.969 (95% CI: 0.728 to 0.990)). For people in HBeAg-negative phases of infection, model-projected HBsAg loss ranged from 0.78% to 3.34% per year depending on HBV DNA level (ICC, 0.889 (95% CI: 0.542 to 0.959)). Model-projected incidence of cirrhosis was 0.29-2.09% per year (ICC, 0.965 (95% CI: 0.942 to 0.979)) and HCC incidence was 0.06-1.65% per year (ICC, 0.977 (95% CI: 0.962 to 0.986)). Over a lifetime simulation of HBV disease, mortality rates were higher for people with older age, higher HBV DNA level and liver-related complications, consistent with observational studies.

CONCLUSIONS

We simulated HBV DNA-stratified clinical outcomes with the novel HEPA-B Model and validated them to observational data. This model can be used to examine strategies of HBV prevention and management.

Implementing 'universal' access to antiretroviral treatment in South Africa: a scoping review on research priorities

‘Universal’ access to antiretroviral treatment (ART) has become the global standard for treating people living with HIV and achieving epidemic control; yet, findings from numerous ‘test and treat’ trials and implementation studies in sub-Saharan Africa suggest that bringing ‘universal' access to ART to scale is more complex than anticipated. Using South Africa as a case example, we describe the research priorities and foci in the literature on expanded ART access. To do so, we adapted Arksey and O’Malley’s six-stage scoping review framework to describe the peer-reviewed literature and opinion pieces on expanding access to ART in South Africa between 2000 and 2017. Data collection included systematic searches of two databases and hand-searching of a sub-sample of reference lists. We used an adapted socio-ecological thematic framework to categorize data according to where it located the challenges and opportunities of expanded ART eligibility: individual/client, health worker–client relationship, clinic/community context, health systems infrastructure and/or policy context. We included 194 research articles and 23 opinion pieces, of 1512 identified, addressing expanded ART access in South Africa. The peer-reviewed literature focused on the individual and health systems infrastructure; opinion pieces focused on changing roles of individuals, communities and health services implementers. We contextualized our findings through a consultative process with a group of researchers, HIV clinicians and programme managers to consider critical knowledge gaps. Unlike the published literature, the consultative process offered particular insights into the importance of researching and intervening in the relational aspects of HIV service delivery as South Africa’s HIV programme expands. An overwhelming focus on individual and health systems infrastructure factors in the published literature on expanded ART access in South Africa may skew understanding of HIV programme shortfalls away from the relational aspects of HIV services delivery and delay progress with finding ways to leverage non-medical modalities for achieving HIV epidemic control.

Costs of implementing community-based intervention for HIV testing in sub-Saharan Africa: a systematic review

Background

Community-based interventions (CBIs) are interventions aimed at improving the well-being of people in a community. CBIs for HIV testing seek to increase the availability of testing services to populations that have been identified as at high risk by reaching them in homes, schools, or community centers. However, evidence for a detailed cost analysis of these community-based interventions in sub-Saharan Africa (SSA) is limited. We conducted a systematic review of the cost analysis of HIV testing interventions in SSA.

Methods

Keyword search was conducted on SCOPUS, CINAHL, MEDLINE, PsycINFO, Web of Science, and Global Health databases. Three categories of key terms used were cost (implementation cost OR cost-effectiveness OR cost analysis OR cost-benefit OR marginal cost), intervention (HIV testing), and region (sub-Saharan Africa OR sub-Saharan Africa OR SSA). CBI studies were included if they primarily focused on HIV testing, was implemented in SSA, and used micro-costing or ingredients approach.

Results

We identified 1533 citations. After screening, ten studies were included in the review: five from East Africa and five from Southern Africa. Two studies conducted cost-effectiveness analysis, and one study was a cost-utility analysis. The remainder seven studies were cost analyses. Four intervention types were identified: HIV self-testing (HIVST), home-based, mobile, and Provider Initiated Testing and Counseling. Commonly costed resources included personnel (n = 9), materials and equipment (n = 6), and training (n = 5). Cost outcomes reported included total intervention cost (n = 9), cost per HIV test (n = 9), cost per diagnosis (n = 5), and cost per linkage to care (n = 3). Overall, interventions were implemented at a higher cost than controls, with the largest cost difference with HIVST compared to facility-based testing.

Conclusion

To better inform policy, there is an urgent need to evaluate the costs associated with implementing CBIs in SSA. It is important for cost reports to be detailed, uniform, and informed by economic evaluation guidelines. This approach minimizes biases that may lead decision-makers to underestimate the resources required to scale up, sustain, or reproduce successful interventions in other settings. In an evolving field of implementation research, this review contributes to current resources on implementation cost studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43058-021-00177-y.

The effects of HIV self-testing on the uptake of HIV testing, linkage to antiretroviral treatment and social harms among adults in Africa: A systematic review and meta-analysis

INTRODUCTION

HIV infection is still a global public health problem. More than 75% of HIV-infected people are in Africa, and up to 54% are unaware of their HIV status, limiting access to antiretroviral treatment.

CONTEXT AND PURPOSE OF THE STUDY

This review aimed to determine whether HIV self-testing (HIVST) increases the uptake of testing, the yield of new HIV-positive diagnoses, and the linkage to antiretroviral treatment, and social harms among adults in Africa.

METHODS

PubMed, The Cochrane Central Register of Controlled Trials (CENTRAL), Pan African Clinical Trials Registry, The Cochrane Database of Systematic Reviews (CDSR), Databases of Abstracts of Reviews of Effectiveness (DARE), Social Sciences Citation Index, Web of Science and African Index Medicus databases were searched from 1998 to 2019 (updated in December 2019). Eligible trials employed randomized controlled trials (RCTs), before/after studies, and interrupted time series design comparing HIVST to standard HIV testing services or comparing different approaches to HIVST among adults living in Africa were systematically sought.

RESULTS

After searching 2,617 citations eleven trials were identified including 59,119 participants from four (4) African countries. Meta-analysis of seven trials showed a significant increase in the uptake of HIVST compared to standard HIV testing services: Both fixed-effects (Rate Ratio (RR) = 2.64, 95% CI: 2.51 to 2.79), and random-effects (RR) = 3.10, 95% CI: 1.80 to 5.37, and a significant increase in the uptake of couples' HIVST (RR = 2.50, 95% CI: 2.29 to 2.73 in fixed-effects models; and RR = 2.64, 95% CI: 2.01 to 3.49 in random-effects model). A decrease in linkage to care and ART was observed in HIVST compared to standard HIV testing services (RR = 0.88, 95% CI: 0.88 to 0.95 in fixed-effects models; and RR = 0.78, 95% CI: 0. 56 to 1.08 in random-effects models). Six RCTs measured social harms, with a total of ten reported cases related to HIVST. One RCT comparing two approaches to HIVST showed that offering home-based HIVST with optional home-initiation of antiretroviral treatment increased the reporting of a positive HIV test result (RR: 1.86; 95% CI: 1.16 to 2.98), and linkage to antiretroviral treatment (RR: 2.94; 95% CI: 2.10 to 4.12), compared with facility-based linkage to antiretroviral treatment.

CONCLUSIONS

HIVST has the potential to increase the uptake of HIV testing compared to standard HIV testing services. Offering HIVST with optional home initiation of HIV care compared to HIVST with facility-based HIV care increases HIV positivity and linkage to antiretroviral treatment. Reported incidences of intimate partner violence related to HIVST were rare. Future research should focus on the potential of HIVST to reach first-time testers, the effect of using different approaches to HIVST, and strategies for linkage to HIV services.

SYSTEMATIC REVIEW REGISTRATION

This systematic review was prospectively registered on the Prospero International Prospective Register of Systematic Review (CRD42015023935).

Multicenter evaluation of Xpert HIV-1 viral load assay for HIV quantification in China

New approaches to increase HIV-1 testing and HIV-1 viral load (VL) monitoring are needed for people living with HIV (PLHIV) in China. The Xpert HIV-1 VL assay was prequalified by the World Health Organization in 2017 but has not been evaluated in China. A multicenter evaluation was conducted to assess the accuracy of the Cepheid Xpert HIV-1 VL assay compared to the Abbott RealTime HIV-1 assay in China. Overall agreement was seen in 558 of 562 specimens (99.29%) with a κ value of 0.962. Pearson's coefficient between the two assays was 0.943. Analyzed by the Bland-Altman method, the mean bias was -0.54 log10  copies/mL, and 94.05% results fell within the 95% confidence limit of agreement (-1.248 to 0.168 log10  copies/mL). The coefficient of variation of the Cepheid Xpert HIV-1 VL assay ranged from 0.61% to 1.55%, as determined by testing eight positive plasma specimens with three different lots on different days. Due to its simplicity, random-access, rapid turnaround time, and accuracy, the Xpert HIV-1 VL assay can be used in local hospitals and clinics that bear the burden of identifying and treating HIV patients in China.

A community-based HIV counselling and testing programme found a decreasing proportion of new HIV testers in South Africa

This article assesses the history of HIV testing among community-based HIV counselling and testing (CBCT) clients between 2014 and 2018 in 13 South African districts. Consenting clients were tested for HIV and interviewed to categorise as first-time testers or repeat testers. Of the 1 800 753 clients tested for HIV, 15.7% (95% CI [15.6-15.7]) were first-time testers. The rate of identifying first-time testers decreased by 10.7% in four years from 18.4% in year one to 7.7% in year four. A substantial proportion (5.5% [5.4-5.6]) of HIV-positive people not yet on antiretroviral treatment sought HIV re-test, of whom nearly half (48.4% [47.1-49.6]) did not disclose their HIV-positive status during pre-counselling and were re-tested. A decreasing proportion of first-time testers may signal positive progress towards universal HIV testing. This downward trend should be sustained to control the HIV epidemic.

Evidence for optimal HIV screening and testing intervals in HIV-negative individuals from various risk groups: A systematic review

Background

Human immunodeficiency virus (HIV) testing plays a crucial role in Canada's HIV prevention and treatment efforts and is the first step to achieving the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets; however, how often Canadians, including populations at increased risk of HIV exposure, should be tested is unclear. We conducted a systematic literature review to determine the optimal HIV screening and testing intervals.

Objective

To examine the current evidence on HIV testing intervals in HIV-negative individuals from various risk groups and to assess the potential harms and patients' values and preferences associated with different testing frequencies.

Methods

We searched MEDLINE/PubMed, Scopus, Embase, the Cochrane Library, PsychINFO and EconLit for studies on different frequencies of HIV testing published between January 2000 and September 2016. An additional search was conducted for grey literature published between January 2000 and October 2016. Data extraction included study characteristics, participants, exposure, outcomes and economic variables. The quality of the studies was assessed and results summarized.

Results

Of the 2,702 articles identified from the searches, 27 met the inclusion criteria for review. This included assessments of HIV testing intervals among the general population, men who have sex with men, people who use injection drugs and sex workers. Optimal testing intervals across risk groups ranged from one-time testing to every three months. Data from modelling studies may not be representative of the Canadian context. Few studies identified potential harms of increased screening, specifically an increase in both false positive and false negative results. There were only two studies that addressed patient values and preferences concerning HIV screening, which suggested that the majority of participants were amenable to routine screening through their primary care provider.

Conclusion

There was insufficient evidence to support optimal HIV screening and testing intervals for different populations. Context-specific factors, such as budget allocation, human resources, local epidemiology, socioeconomic factors and risk behaviours, along with clinical judgement, inform whom and how often to screen, suggesting the need for research specific to Canada. Research on patient preferences as well as the benefits and harms of more frequent screening are also indicated.

Success factors for universal access to antiretroviral treatments in South Africa

This article studies the epidemiological and economic impacts of a universal testing and treatment policy of Human Immunodeficiency Virus (HIV) in South Africa. A model of disease transmission is built to simulate several implementation scenarios of the policy. Different behavioral responses in the general population are considered. The results show that the success of a large-scale HIV testing and treatment program in South Africa depends on its implementation conditions. The policy can lead to a reduction of the HIV epidemic, even in the case of a large relapse in preventive behaviors in the general population, if implementation conditions are favorable. This is the case if the number of infected individuals who are infectious is greatly reduced. From an economic point of view, taking into account the positive externality of antiretroviral (ARV) treatments changes the traditional framework of cost-benefit analyses. A large-scale testing and treatment program would be cost-saving in the case of favorable implementation conditions, even following a large increase in risk behaviors after the scaling up of ARV treatments. By contrast, the analysis stresses out the potential perverse effects of scaling up ARV treatments in South Africa if the intervention is set up without ensuring enough resources for patients' monitoring and the availability of effective ARV drugs. Indeed, if the number of treated patients rises while adherence of patients to treatments decreases and the rate of loss to follow-up increases, the policy could extend the pool of infectious patients and lead to a long-term amplification of the epidemic.

Actual Versus Perceived HIV Testing Norms, and Personal HIV Testing Uptake: A Cross-Sectional, Population-Based Study in Rural Uganda

HIV testing is an essential part of treatment and prevention. Using population-based data from 1664 adults across eight villages in rural Uganda, we assessed individuals' perception of the norm for HIV testing uptake in their village and compared it to the actual uptake norm. In addition, we examined how perception of the norm was associated with personal testing while adjusting for other factors. Although the majority of people had been tested for HIV across all villages, slightly more than half of men and women erroneously thought that the majority in their village had never been tested. They underestimated the prevalence of HIV testing uptake by 42 percentage points (s.d. = 17 percentage points), on average. Among men, perceiving that HIV testing was not normative was associated with never testing for HIV (AOR = 2.6; 95% CI 1.7-4.0, p < 0.001). Results suggest an opportunity for interventions to emphasize the commonness of HIV testing uptake.

Determining Preferences Related to HIV Counselling and Testing Services Among High School Learners in KwaZulu-Natal: A Discrete Choice Experiment

A key strategy of the South African national response to HIV is the scale-up of HIV counselling and testing (HCT) in the 15-49 years age group. The integrated school health policy aims to guide the roll out of youth-friendly health services including the provision of HCT in schools. Using a discrete choice experiment to examine preferences regarding the attributes of HCT service packages, this study identifies barriers to and facilitators of HCT among high school learners. Monetary considerations were found to have the strongest effect of any attribute on choice, whilst confidentiality was found to be a primary concern for learners considering HCT. Policy makers and service providers must ensure that confidentiality is maintained, and could consider using monetary incentives as a way of increasing uptake of HCT. Programmes designed to reduce social stigma and improve education and knowledge dissemination around HCT and HIV, are vital in creating demand for HCT and changing attitudes among young people.

Improving the clinic-laboratory-interface in the context of HIV diagnosis, treatment, and monitoring

PURPOSE OF REVIEW

Laboratory support is central to clinical medicine. The present review focuses on the health systems strengthening needs of the clinic-laboratory-interface (CLI) in developing countries within the context of HIV diagnosis, treatment, and monitoring.

RECENT FINDINGS

Although significant improvements have been made in reducing error rates in the analytical phase of pathology services within laboratories, there remain substantial deficits in both the preanalytic and postanalytic phases of the entire value chain that require strengthening. Recent interventions have largely aimed at improving the CLI focus through technological advancements. Although these are important, addressing CLI deficiencies within the context of the World Health Organization's health systems strengthening building blocks has been relatively neglected, and data are very limited in resource-limited countries. Broad health systems strengthening in the CLI is required. The present study reviews the key elements of the CLI associated with poor laboratory functioning, and proposes specific areas for improvement. The present study discuss case studies in South Africa and India, as well as reviewing data supporting interventions in public health clinics to improve the CLI.

SUMMARY

The CLI is a neglected area of the laboratory value chain. Reducing errors and increasing efficiencies will improve the laboratory service to patients.

Operations research in global health: a scoping review with a focus on the themes of health equity and impact

BACKGROUND

Operations research (OR) is a discipline that uses advanced analytical methods (e.g. simulation, optimisation, decision analysis) to better understand complex systems and aid in decision-making. Herein, we present a scoping review of the use of OR to analyse issues in global health, with an emphasis on health equity and research impact. A systematic search of five databases was designed to identify relevant published literature. A global overview of 1099 studies highlights the geographic distribution of OR and common OR methods used. From this collection of literature, a narrative description of the use of OR across four main application areas of global health - health systems and operations, clinical medicine, public health and health innovation - is also presented. The theme of health equity is then explored in detail through a subset of 44 studies. Health equity is a critical element of global health that cuts across all four application areas, and is an issue particularly amenable to analysis through OR. Finally, we present seven select cases of OR analyses that have been implemented or have influenced decision-making in global health policy or practice. Based on these cases, we identify three key drivers for success in bridging the gap between OR and global health policy, namely international collaboration with stakeholders, use of contextually appropriate data, and varied communication outlets for research findings. Such cases, however, represent a very small proportion of the literature found.

CONCLUSION

Poor availability of representative and quality data, and a lack of collaboration between those who develop OR models and stakeholders in the contexts where OR analyses are intended to serve, were found to be common challenges for effective OR modelling in global health.

Can the Heterosexual HIV Epidemic be Eliminated in South Africa Using Combination Prevention? A Modeling Analysis

Little is known about how combining efficacious interventions for human immunodeficiency virus (HIV) prevention could lead to HIV elimination. We used an agent-based simulation model, the HIV calibrated dynamic model, to assess the potential for HIV elimination in South Africa. We examined several scenarios (from continuation of the current status quo to perfect achievement of targets) with differing combinations of male condom use, adult male circumcision, HIV testing, and early antiretroviral therapy (ART). We varied numerous parameters, including the proportion of adult males circumcised, the frequency of condom use during sex acts, acceptance of HIV testing, linkage to health care, criteria for ART initiation, ART viral suppression rates, and loss to follow-up. Maintaining current levels of combination prevention would lead to increasing HIV incidence and prevalence in South Africa, while the perfect combination scenario was projected to eliminate HIV on a 50-year time scale from 2013 to 2063. Perfecting testing and treatment, without changing condom use or circumcision rates, resulted in an 89% reduction in HIV incidence but not elimination. Universal adult male circumcision alone resulted in a 21% incidence reduction within 20 years. Substantial decreases in HIV incidence are possible from sufficient uptake of both primary prevention and ART, but with continuation of the status quo, HIV elimination in South Africa is unlikely within a 50-year time scale.

Home testing and counselling to reduce HIV incidence in a generalised epidemic setting: a mathematical modelling analysis

BACKGROUND

Home HIV testing and counselling (HTC) achieves high levels of HIV testing and linkage to care. Periodic home HTC, particularly targeted to those with high HIV viral load, might facilitate expansion of antiretroviral therapy (ART) coverage. We used a mathematical model to assess the effect of periodic home HTC programmes on HIV incidence in KwaZulu-Natal, South Africa.

METHODS

We developed a dynamic HIV transmission model with parameters, primary cost data, and measures of viral suppression collected from a prospective study of home HTC in KwaZulu-Natal. In our model, we assumed home HTC took place every 5 years with ART initiation for people with CD4 counts of 350 cells per μL or less. For individuals with CD4 counts of more than 350 cells per μL, we compared increasing ART coverage for those with 350-500 cells per μL with initiating treatment for those who have viral loads of more than 10 000 copies per mL.

FINDINGS

Maintaining the presently observed level of 36% viral suppression in HIV-positive people, HIV incidence decreases by 33·8% over 10 years. Home HTC every 5 years with linkage to care with ART initiation at CD4 counts of 350 cells per μL or less reduces HIV incidence by 40·6% over 10 years. Expansion of ART to people with CD4 counts of more than 350 cells per μL who also have a viral load of 10 000 copies per mL or more decreases HIV incidence by 51·6%, and this was the most cost-effective strategy for prevention of HIV infections at US$2960 per infection averted. Expansion of ART eligibility CD4 counts of 350-500 cells per μL is cost-effective at $900 per quality-adjusted life-year gained. Following health economic guidelines, expansion of ART use to individuals who have viral loads of more than 10 000 copies per mL among those with CD4 counts of more than 350 cells per μL was cost-effective to reduce HIV-related morbidity.

INTERPRETATION

Our results show that province-wide home HTC every 5 years can be a cost-effective strategy to increase ART coverage and reduce HIV burden. Expanded ART initiation criteria that includes individuals with high viral load will improve the effectiveness of home HTC in linking individuals to ART who are at high risk of transmitting HIV, thereby preventing morbidity and onward transmission.

FUNDING

National Institutes of Health.

The effects of HIV self-testing on the uptake of HIV testing and linkage to antiretroviral treatment among adults in Africa: a systematic review protocol

BACKGROUND

HIV is still a global public health problem. More than 75 % of HIV-infected people are in Africa, and most of them are unaware of their HIV status, which is a barrier to accessing antiretroviral treatment. Our review aims, firstly, to determine whether HIV self-testing is an effective method to increase the uptake of testing, the yield of new HIV-positive diagnoses, and the linkage to antiretroviral treatment. Secondly, we aim to review the factors that facilitate or impede the uptake of HIV self-testing.

METHODS/DESIGN

Participants will be adults living in Africa. For the first aim, the intervention will be HIV self-testing either alone or in addition to HIV testing standard of care. The comparison will be HIV testing standard of care. The primary outcomes will be (i) uptake of HIV testing and (ii) yield of new HIV-positive diagnoses. The secondary outcomes will be (a) linkage to antiretroviral (ARV) treatment and (b) incidence of social harms. For the second aim, we will review barriers and facilitators to the uptake of self-testing. We will search PubMed, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, WHOLIS, Africa Wide, and CINAHL for eligible studies from 1998, with no language limits. We will check reference lists of included studies for other eligible reports. Eligible studies will include experimental and observational studies. Two authors will independently screen the search output, select studies, and extract data, resolving discrepancies by consensus and discussion. Two authors will use Cochrane risk of bias tools for experimental studies, the Newcastle-Ottawa Quality Assessment Scale for observational studies, and the Critical Appraisal Skills Programme (CASP) quality assessment tool for qualitative studies.

DISCUSSION

Innovative and cost-effective community-based HIV testing strategies, such as self-testing, will contribute to universal coverage of HIV testing in Africa. The findings from this systematic review will guide development of self-testing policy in African countries.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015023935.

Are Clade Specific HIV Vaccines a Necessity? An Analysis Based on Mathematical Models

As HIV-1 envelope immune responses are critical to vaccine related protection, most candidate HIV vaccines entering efficacy trials are based upon a clade specific design. This need for clade specific vaccine prototypes markedly reduces the implementation of potentially effective HIV vaccines. We utilized a mathematical model to determine the effectiveness of immediate roll-out of a non-clade matched vaccine with reduced efficacy compared to constructing clade specific vaccines, which would take considerable time to manufacture and test in safety and efficacy trials. We simulated the HIV epidemic in San Francisco (SF) and South Africa (SA) and projected effectiveness of three vaccination strategies: i) immediate intervention with a 20–40% vaccine efficacy (VE) non-matched vaccine, ii) delayed intervention by developing a 50% VE clade-specific vaccine, and iii) immediate intervention with a non-matched vaccine replaced by a clade-specific vaccine when developed. Immediate vaccination with a non-clade matched vaccine, even with reduced efficacy, would prevent thousands of new infections in SF and millions in SA over 30 years. Vaccination with 50% VE delayed for five years needs six and 12 years in SA to break-even with immediate 20 and 30% VE vaccination, respectively, while not able to surpass the impact of immediate 40% VE vaccination over 30 years. Replacing a 30% VE with a 50% VE vaccine after 5 years reduces the HIV acquisition by 5% compared to delayed vaccination. The immediate use of an HIV vaccine with reduced VE in high risk communities appears desirable over a short time line but higher VE should be the pursued to achieve strong long-term impact. Our analysis illustrates the importance of developing surrogate markers (correlates of protection) to allow bridging types of immunogenicity studies to support more rapid assessment of clade specific vaccines.

•

Rapid deployment of non-clade matched HIV vaccines would be an effective public-health strategy in high risk populations.

•

Pursuit of further incremental increase in vaccine efficacy is justified and will result in better long term effectiveness.

•

Reduced condom use by vaccinated individuals may diminish the advantage of the replacement vaccination strategy.

•

Reliable surrogate markers of vaccine efficacy are needed to speed up the development of effective HIV vaccines.

The HIV vaccine field has followed the concept of clade specific (clade matched) vaccines for over 30 years. We investigate the implementation of non-clade matched and clade specific vaccines by simulating the HIV epidemics in San Francisco and South Africa: two regions of the world where the epidemics are well characterized. Our analysis suggests that rapid deployment of a non-clade matched vaccine would be an effective public health strategy. The most effective 10-year vaccination strategy is to employ non-clade matched vaccines in highest risk populations followed by the rapid development of a more effective clade matched prototype.

A qualitative analysis of the barriers and facilitators of HIV counselling and testing perceived by adolescents in South Africa

BACKGROUND

Youth in South Africa have been identified as a high-risk group for contracting HIV. In response, the South African Integrated School Health Policy (ISHP) has been developed with the aim of guiding the provision of comprehensive healthcare services within South African schools. Accordingly, the scale-up of HIV counselling and testing (HCT) in high schools is a priority. This study examines the factors affecting the utilisation of HCT services amongst learners in high schools in the KwaZulu-Natal province of South Africa.

METHODS

Focus group discussions were conducted in 12 rural schools in the Vulindlela sub-district of uMgungundlovu in KwaZulu-Natal. A total of 158 randomly selected learners took part, aged 16 years and older from grades 10, 11 and 12. Qualitative analysis was conducted using the framework approach, providing a systematic structure allowing for a priori and emergent codes, with social cognitive theory as a theoretical framework.

RESULTS

The stigma and discrimination attached to testing, along with the inherent fear of a positive result were the biggest barriers to HCT uptake. Fear and the subsequent negative beliefs around HCT were borne out of insufficient knowledge. These fears were exacerbated by the perceived or real attitudes of peers, partners and family towards HIV. The prospect of a positive result and the possible resultant societal backlash hinders high and regular uptake of HCT. Stigma and discrimination remain the foremost barriers to HIV testing despite the presence of localised and convenient testing. Interventions aimed at addressing these challenges could increase the demand for HIV testing amongst adolescents.

CONCLUSIONS

Increasing education about the importance of HCT and creating awareness about available HCT services will not be enough to increase uptake in schools in South Africa. Efforts to decrease stigma around HIV and HCT by integrating testing into general and sexual reproductive health services offered to youth, and normalising the epidemic within the community could go some way to allaying the fears shrouding testing, if such services are designed with the specific needs of youth in mind. This paper adds to the body of literature informing the design of policy in South Africa aimed at integrating HCT into school health services.

Opportunities for strengthening provider-initiated testing and counselling for HIV in Namibia

This short report identifies enablers and barriers to the uptake of provider-initiated testing and counselling for HIV (PITC) in Namibia and identifies key opportunities for strengthening this vital aspect of the national HIV response. We explored this through facility mapping, register reviews and qualitative methods including focus group discussions and in-depth interviews. Four health facilities (clinics and hospitals) in two regions were included in the study. We identified that PITC in Namibia was largely delivered by lay counsellors operating in designated rapid testing rooms located in health facilities and found a large number of missed opportunities for HIV testing through this model. Nurses did not see it as an integral part of their role, were not aware of HIV testing and counselling policy, felt inadequately trained and supported, and experienced staffing shortages. Institutional issues also acted as barriers to nurses performing or initiating discussions about PITC. Wider dissemination and implementation of policy, increasing privacy of consultation spaces and community sensitisation are simple measures that represent opportunities for strengthening this response and ensuring that symptomatic individuals who are unaware of their HIV status do not fall through the net.

Using geospatial modelling to optimize the rollout of antiretroviral-based pre-exposure HIV interventions in Sub-Saharan Africa

Antiretroviral-based pre-exposure HIV interventions may soon be rolled out in resource-constrained Sub-Saharan African countries, but rollout plans have yet to be designed. Here we use geospatial modeling and optimization techniques to compare two rollout plans for ARV-based microbicides in South Africa: a utilitarian plan that minimizes incidence by using geographic targeting, and an egalitarian plan that maximizes geographic equity in access to interventions. We find significant geographic variation in the efficiency of interventions in reducing HIV transmission, and that efficiency increases disproportionately with increasing incidence. The utilitarian plan would result in considerable geographic inequity in access to interventions, but (by exploiting geographic variation in incidence) could prevent ~40% more infections than the egalitarian plan. Our results show that the geographic resource allocation decisions made at the beginning of a rollout, and the location where the rollout is initiated, will be crucial in determining the success of interventions in reducing HIV epidemics.

HIV, tuberculosis, and noncommunicable diseases: what is known about the costs, effects, and cost-effectiveness of integrated care?

Unprecedented investments in health systems in low- and middle-income countries (LMICs) have resulted in more than 8 million individuals on antiretroviral therapy. Such individuals experience dramatically increased survival but are increasingly at risk of developing common noncommunicable diseases (NCDs). Integrating clinical care for HIV, other infectious diseases, and NCDs could make health services more effective and provide greater value. Cost-effectiveness analysis is a method to evaluate the clinical benefits and costs associated with different health care interventions and offers guidance for prioritization of investments and scale-up, especially as resources are increasingly constrained. We first examine tuberculosis and HIV as 1 example of integrated care already successfully implemented in several LMICs; we then review the published literature regarding cervical cancer and depression as 2 examples of NCDs for which integrating care with HIV services could offer excellent value. Direct evidence of the benefits of integrated services generally remains scarce; however, data suggest that improved effectiveness and reduced costs may be attained by integrating additional services with existing HIV clinical care. Further investigation into clinical outcomes and costs of care for NCDs among people living with HIV in LMICs will help to prioritize specific health care services by contributing to an understanding of the affordability and implementation of an integrated approach.

A comparison of linkage to HIV care after provider-initiated HIV testing and counselling (PITC) versus voluntary HIV counselling and testing (VCT) for patients with sexually transmitted infections in Cape Town, South Africa

BACKGROUND

We examined linkage to care for patients with sexually transmitted infection who were diagnosed HIV-positive via the provider-initiated HIV testing and counselling (PITC) approach, as compared to the voluntary counselling and testing (VCT) approach, as little is known about the impact of expanded testing strategies on linkage to care.

METHODS

In a controlled trial on PITC (Cape Town, 2007), we compared HIV follow-up care for a nested cohort of 930 HIV-positive patients. We cross-referenced HIV testing and laboratory records to determine access to CD4 and viral load testing as primary outcomes. Secondary outcomes were HIV immune status and time taken to be linked to HIV care. Logistic regression was performed to analyse the difference between arms.

RESULTS

There was no difference in the main outcomes of patients with a record of CD4 testing (69.9% in the intervention, 65.2% in control sites, OR 0.82 (CI: 0.44-1.51; p = 0.526) and viral load testing (14.9% intervention versus 10.9% control arm; OR 0.69 (CI: 0.42-1.12; p = 0.131). In the intervention arm, ART-eligible patients (based on low CD4 test result), accessed viral load testing approximately 2.5 months sooner than those in the control arm (214 days vs. 288 days, HR: 0.417, 95% CI: 0.221-0.784; p = 0.007).

CONCLUSION

The PITC intervention did not improve linkage to CD4 testing, but shortened the time to viral load testing for ART-eligible patients. Major gaps found in follow-up care across both arms, indicate the need for more effective linkage-to-HIV care strategies.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN93692532.

Modelling the potential population impact and cost-effectiveness of self-testing for HIV: evaluation of data requirements

HIV testing uptake has increased dramatically in recent years in resource limited settings. Nevertheless, over 50 % of the people living with HIV are still unaware of their status. HIV self-testing (HIVST) is a potential new approach to facilitate further uptake of testing which requires consideration, taking into account economic factors. Mathematical models and associated economic analysis can provide useful assistance in decision-making processes, offering insight, in this case, into the potential long-term impact at a population level and the price-point at which free or subsidized HIVST would be cost-effective in a given setting. However, models are based on assumptions, and if the required data are sparse or limited, this uncertainty will be reflected in the results from mathematical models. The aim of this paper is to describe the issues encountered in modeling the cost-effectiveness of introducing HIVST, to indicate the evidence needed to support various modeling assumptions, and thus which data on HIVST would be most beneficial to collect.

Development, calibration and performance of an HIV transmission model incorporating natural history and behavioral patterns: application in South Africa

Understanding HIV transmission dynamics is critical to estimating the potential population-wide impact of HIV prevention and treatment interventions. We developed an individual-based simulation model of the heterosexual HIV epidemic in South Africa and linked it to the previously published Cost-Effectiveness of Preventing AIDS Complications (CEPAC) International Model, which simulates the natural history and treatment of HIV. In this new model, the CEPAC Dynamic Model (CDM), the probability of HIV transmission per sexual encounter between short-term, long-term and commercial sex worker partners depends upon the HIV RNA and disease stage of the infected partner, condom use, and the circumcision status of the uninfected male partner. We included behavioral, demographic and biological values in the CDM and calibrated to HIV prevalence in South Africa pre-antiretroviral therapy. Using a multi-step fitting procedure based on Bayesian melding methodology, we performed 264,225 simulations of the HIV epidemic in South Africa and identified 3,750 parameter sets that created an epidemic and had behavioral characteristics representative of a South African population pre-ART. Of these parameter sets, 564 contributed 90% of the likelihood weight to the fit, and closely reproduced the UNAIDS HIV prevalence curve in South Africa from 1990–2002. The calibration was sensitive to changes in the rate of formation of short-duration partnerships and to the partnership acquisition rate among high-risk individuals, both of which impacted concurrency. Runs that closely fit to historical HIV prevalence reflect diverse ranges for individual parameter values and predict a wide range of possible steady-state prevalence in the absence of interventions, illustrating the value of the calibration procedure and utility of the model for evaluating interventions. This model, which includes detailed behavioral patterns and HIV natural history, closely fits HIV prevalence estimates.

Incidence of TB and HIV in prospectively followed household contacts of TB index patients in South Africa

Objective

To report the incidence rates of TB and HIV in household contacts of index patients diagnosed with TB.

Design

A prospective cohort study in the Matlosana sub-district of North West Province, South Africa.

Methods

Contacts of index TB patients received TB and HIV testing after counseling at their first household visit and were then followed up a year later, in 2010. TB or HIV diagnoses that occurred during the period were determined.

Results

For 2,377 household contacts, the overall observed TB incidence rate was 1.3 per 100 person years (95% CI 0.9–1.9/100py) and TB incidence for individuals who were HIV-infected and HIV seronegative at baseline was 5.4/100py (95% CI 2.9–9.0/100py) and 0.7/100py (95% CI 0.3–1.4/100py), respectively. The overall HIV incidence rate was 2.2/100py (95% CI 1.3–8.4/100py).

Conclusions

In the year following a household case finding visit when household contacts were tested for TB and HIV, the incidence rate of both active TB and HIV infection was found to be extremely high. Clearly, implementing proven strategies to prevent HIV acquisition and preventing TB transmission and progression to disease remains a priority in settings such as South Africa.

Heterogeneous HIV testing preferences in an urban setting in Tanzania: results from a discrete choice experiment

BACKGROUND

Efforts to reduce Human Immunodeficiency Virus (HIV) transmission through treatment rely on HIV testing programs that are acceptable to broad populations. Yet, testing preferences among diverse at-risk populations in Sub-Saharan Africa are poorly understood. We fielded a population-based discrete choice experiment (DCE) to evaluate factors that influence HIV-testing preferences in a low-resource setting.

METHODS

Using formative work, a pilot study, and pretesting, we developed a DCE survey with five attributes: distance to testing, confidentiality, testing days (weekday vs. weekend), method for obtaining the sample for testing (blood from finger or arm, oral swab), and availability of HIV medications at the testing site. Cluster-randomization and Expanded Programme on Immunization (EPI) sampling methodology were used to enroll 486 community members, ages 18-49, in an urban setting in Northern Tanzania. Interviewer-assisted DCEs, presented to participants on iPads, were administered between September 2012 and February 2013.

RESULTS

Nearly three of five males (58%) and 85% of females had previously tested for HIV; 20% of males and 37% of females had tested within the past year. In gender-specific mixed logit analyses, distance to testing was the most important attribute to respondents, followed by confidentiality and the method for obtaining the sample for the HIV test. Both unconditional assessments of preferences for each attribute and mixed logit analyses of DCE choice patterns suggest significant preference heterogeneity among participants. Preferences differed between males and females, between those who had previously tested for HIV and those who had never tested, and between those who tested in the past year and those who tested more than a year ago.

CONCLUSION

The findings suggest potentially significant benefits from tailoring HIV testing interventions to match the preferences of specific populations, including males and females and those who have never tested for HIV.

Mobile HIV screening in Cape Town, South Africa: clinical impact, cost and cost-effectiveness

BACKGROUND

Mobile HIV screening may facilitate early HIV diagnosis. Our objective was to examine the cost-effectiveness of adding a mobile screening unit to current medical facility-based HIV testing in Cape Town, South Africa.

METHODS AND FINDINGS

We used the Cost Effectiveness of Preventing AIDS Complications International (CEPAC-I) computer simulation model to evaluate two HIV screening strategies in Cape Town: 1) medical facility-based testing (the current standard of care) and 2) addition of a mobile HIV-testing unit intervention in the same community. Baseline input parameters were derived from a Cape Town-based mobile unit that tested 18,870 individuals over 2 years: prevalence of previously undiagnosed HIV (6.6%), mean CD4 count at diagnosis (males 423/µL, females 516/µL), CD4 count-dependent linkage to care rates (males 31%-58%, females 49%-58%), mobile unit intervention cost (includes acquisition, operation and HIV test costs, $29.30 per negative result and $31.30 per positive result). We conducted extensive sensitivity analyses to evaluate input uncertainty. Model outcomes included site of HIV diagnosis, life expectancy, medical costs, and the incremental cost-effectiveness ratio (ICER) of the intervention compared to medical facility-based testing. We considered the intervention to be "very cost-effective" when the ICER was less than South Africa's annual per capita Gross Domestic Product (GDP) ($8,200 in 2012). We projected that, with medical facility-based testing, the discounted (undiscounted) HIV-infected population life expectancy was 132.2 (197.7) months; this increased to 140.7 (211.7) months with the addition of the mobile unit. The ICER for the mobile unit was $2,400/year of life saved (YLS). Results were most sensitive to the previously undiagnosed HIV prevalence, linkage to care rates, and frequency of HIV testing at medical facilities.

CONCLUSION

The addition of mobile HIV screening to current testing programs can improve survival and be very cost-effective in South Africa and other resource-limited settings, and should be a priority.

Routine HIV screening in Portugal: clinical impact and cost-effectiveness

OBJECTIVE

To compare the clinical outcomes and cost-effectiveness of routine HIV screening in Portugal to the current practice of targeted and on-demand screening.

DESIGN

We used Portuguese national clinical and economic data to conduct a model-based assessment.

METHODS

We compared current HIV detection practices to strategies of increasingly frequent routine HIV screening in Portuguese adults aged 18-69. We considered several subpopulations and geographic regions with varying levels of undetected HIV prevalence and incidence. Baseline inputs for the national case included undiagnosed HIV prevalence 0.16%, annual incidence 0.03%, mean population age 43 years, mean CD4 count at care initiation 292 cells/μL, 63% HIV test acceptance, 78% linkage to care, and HIV rapid test cost €6 under the proposed routine screening program. Outcomes included quality-adjusted survival, secondary HIV transmission, cost, and incremental cost-effectiveness.

RESULTS

One-time national HIV screening increased HIV-infected survival from 164.09 quality-adjusted life months (QALMs) to 166.83 QALMs compared to current practice and had an incremental cost-effectiveness ratio (ICER) of €28,000 per quality-adjusted life year (QALY). Screening more frequently in higher-risk groups was cost-effective: for example screening annually in men who have sex with men or screening every three years in regions with higher incidence and prevalence produced ICERs of €21,000/QALY and €34,000/QALY, respectively.

CONCLUSIONS

One-time HIV screening in the Portuguese national population will increase survival and is cost-effective by international standards. More frequent screening in higher-risk regions and subpopulations is also justified. Given Portugal's challenging economic priorities, we recommend prioritizing screening in higher-risk populations and geographic settings.

Health benefits, costs, and cost-effectiveness of earlier eligibility for adult antiretroviral therapy and expanded treatment coverage: a combined analysis of 12 mathematical models

BACKGROUND

New WHO guidelines recommend ART initiation for HIV-positive persons with CD4 cell counts ≤500 cells/µL, a higher threshold than was previously recommended. Country decision makers must consider whether to further expand ART eligibility accordingly.

METHODS

We used multiple independent mathematical models in four settings-South Africa, Zambia, India, and Vietnam-to evaluate the potential health impact, costs, and cost-effectiveness of different adult ART eligibility criteria under scenarios of current and expanded treatment coverage, with results projected over 20 years. Analyses considered extending eligibility to include individuals with CD4 ≤500 cells/µL or all HIV-positive adults, compared to the previous recommendation of initiation with CD4 ≤350 cells/µL. We assessed costs from a health system perspective, and calculated the incremental cost per DALY averted ($/DALY) to compare competing strategies. Strategies were considered 'very cost-effective' if the $/DALY was less than the country's per capita gross domestic product (GDP; South Africa: $8040, Zambia: $1425, India: $1489, Vietnam: $1407) and 'cost-effective' if $/DALY was less than three times per capita GDP.

FINDINGS

In South Africa, the cost per DALY averted of extending ART eligibility to CD4 ≤500 cells/µL ranged from $237 to $1691/DALY compared to 2010 guidelines; in Zambia, expanded eligibility ranged from improving health outcomes while reducing costs (i.e. dominating current guidelines) to $749/DALY. Results were similar in scenarios with substantially expanded treatment access and for expanding eligibility to all HIV-positive adults. Expanding treatment coverage in the general population was therefore found to be cost-effective. In India, eligibility for all HIV-positive persons ranged from $131 to $241/DALY and in Vietnam eligibility for CD4 ≤500 cells/µL cost $290/DALY. In concentrated epidemics, expanded access among key populations was also cost-effective.

INTERPRETATION

Earlier ART eligibility is estimated to be very cost-effective in low- and middle-income settings, although these questions should be revisited as further information becomes available. Scaling-up ART should be considered among other high-priority health interventions competing for health budgets.

FUNDING

The Bill and Melinda Gates Foundation and World Health Organization.

HIV testing: current practice and future directions

New approaches to expanding HIV testing and effective treatment and the wider availability of rapid testing technology have created new opportunities for achieving national and global HIV testing goals. In spite of HIV testing expansion in many settings, growing evidence of the prevention benefits of HIV testing, and the development of new, cost-effective approaches to HIV testing service provision, formidable obstacles to HIV testing expansion persist. Inequitable testing coverage exists within and across countries. While the proportion of people with HIV aware of their status is about 80% in the U.S., the majority of HIV-infected persons in Africa are unaware of their status. Testing of most-at-risk populations, couples, children, and adolescents pose still unresolved policy and programmatic challenges. Future directions for HIV testing include rapid testing technology and detection of acute HIV infection, self-testing expansion, and partner notification. Expanded routine HIV screening and widespread testing is a public health imperative to reach national and international HIV prevention and treatment goals.

Diagnostic point-of-care tests in resource-limited settings

The aim of diagnostic point-of-care testing is to minimise the time to obtain a test result, thereby allowing clinicians and patients to make a quick clinical decision. Because point-of-care tests are used in resource-limited settings, the benefits need to outweigh the costs. To optimise point-of-care testing in resource-limited settings, diagnostic tests need rigorous assessments focused on relevant clinical outcomes and operational costs, which differ from assessments of conventional diagnostic tests. We reviewed published studies on point-of-care testing in resource-limited settings, and found no clearly defined metric for the clinical usefulness of point-of-care testing. Therefore, we propose a framework for the assessment of point-of-care tests, and suggest and define the term test efficacy to describe the ability of a diagnostic test to support a clinical decision within its operational context. We also propose revised criteria for an ideal diagnostic point-of-care test in resource-limited settings. Through systematic assessments, comparisons between centralised testing and novel point-of-care technologies can be more formalised, and health officials can better establish which point-of-care technologies represent valuable additions to their clinical programmes.

The survival benefits of antiretroviral therapy in South Africa

BACKGROUND

We sought to quantify the survival benefits attributable to antiretroviral therapy (ART) in South Africa since 2004.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications-International model (CEPAC) to simulate 8 cohorts of human immunodeficiency virus (HIV)-infected patients initiating ART each year during 2004-2011. Model inputs included cohort-specific mean CD4(+) T-cell count at ART initiation (112-178 cells/µL), 24-week ART suppressive efficacy (78%), second-line ART availability (2.4% of ART recipients), and cohort-specific 36-month retention rate (55%-71%). CEPAC simulated survival twice for each cohort, once with and once without ART. The sum of the products of per capita survival differences and the total numbers of persons initiating ART for each cohort yielded the total survival benefits.

RESULTS

Lifetime per capita survival benefits ranged from 9.3 to 10.2 life-years across the 8 cohorts. Total estimated population lifetime survival benefit for all persons starting ART during 2004-2011 was 21.7 million life-years, of which 2.8 million life-years (12.7%) had been realized by December 2012. By 2030, benefits reached 17.9 million life-years under current policies, 21.7 million life-years with universal second-line ART, 23.3 million life-years with increased linkage to care of eligible untreated patients, and 28.0 million life-years with both linkage to care and universal second-line ART.

CONCLUSIONS

We found dramatic past and potential future survival benefits attributable to ART, justifying international support of ART rollout in South Africa.

Balancing efficiency, equity and feasibility of HIV treatment in South Africa - development of programmatic guidance

South Africa, the country with the largest HIV epidemic worldwide, has been scaling up treatment since 2003 and is rapidly expanding its eligibility criteria. The HIV treatment programme has achieved significant results, and had 1.8 million people on treatment per 2011. Despite these achievements, it is now facing major concerns regarding (i) efficiency: alternative treatment policies may save more lives for the same budget; (ii) equity: there are large inequalities in who receives treatment; (iii) feasibility: still only 52% of the eligible population receives treatment.Hence, decisions on the design of the present HIV treatment programme in South Africa can be considered suboptimal. We argue there are two fundamental reasons to this. First, while there is a rapidly growing evidence-base to guide priority setting decisions on HIV treatment, its included studies typically consider only one criterion at a time and thus fail to capture the broad range of values that stakeholders have. Second, priority setting on HIV treatment is a highly political process but it seems no adequate participatory processes are in place to incorporate stakeholders' views and evidences of all sorts.We propose an alternative approach that provides a better evidence base and outlines a fair policy process to improve priority setting in HIV treatment. The approach integrates two increasingly important frameworks on health care priority setting: accountability for reasonableness (A4R) to foster procedural fairness, and multi-criteria decision analysis (MCDA) to construct an evidence-base on the feasibility, efficiency, and equity of programme options including trade-offs. The approach provides programmatic guidance on the choice of treatment strategies at various decisions levels based on a sound conceptual framework, and holds large potential to improve HIV priority setting in South Africa.

Implementing a provider-initiated testing and counselling (PITC) intervention in Cape town, South Africa: a process evaluation using the normalisation process model

Background

Provider-initiated HIV testing and counselling (PITC) increases HIV testing rates in most settings, but its effect on testing rates varies considerably. This paper reports the findings of a process evaluation of a controlled trial of PITC for people with sexually transmitted infections (STI) attending publicly funded clinics in a low-resource setting in South Africa, where the trial results were lower than anticipated compared to the standard Voluntary Counselling and Testing (VCT) approach.

Method

This longitudinal study used a variety of qualitative methods, including participant observation of project implementation processes, staff focus groups, patient interviews, and observation of clinical practice. Data were content analysed by identifying the main influences shaping the implementation process. The Normalisation Process Model (NPM) was used as a theoretical framework to analyse implementation processes and explain the trial outcomes.

Results

The new PITC intervention became embedded in practice (normalised) during a two-year period (2006 to 2007). Factors that promoted the normalising include strong senior leadership, implementation support, appropriate accountability mechanisms, an intervention design that was responsive to service needs and congruent with professional practice, positive staff and patient perceptions, and a responsive organisational context. Nevertheless, nurses struggled to deploy the intervention efficiently, mainly because of poor sequencing and integration of HIV and STI tasks, a focus on HIV education, tension with a patient-centred communication style, and inadequate training on dealing with the operational challenges. This resulted in longer consultation times, which may account for the low test coverage outcome.

Conclusion

Leadership and implementation support, congruent intervention design, and a responsive organisational context strengthened implementation. Poor compatibility with nurse skills on the level of the clinical consultation may have contributed to limiting the size of the trial outcomes. A close fit between the PITC intervention design and clinical practices, as well as appropriate training, are needed to ensure sustainability of the programme. The use of a theory-driven analysis promotes transferability of the results, and the findings are therefore relevant to the implementation of HIV testing and to the design and evaluation of complex interventions in other settings.

Trial registration

Current controlled trials ISRCTN93692532

Translation of biomedical prevention strategies for HIV: prospects and pitfalls

Early achievements in biomedical approaches for HIV prevention included physical barriers (condoms), clean injection equipment (both for medical use and for injection drug users), blood and blood product safety, and prevention of mother-to-child transmission. In recent years, antiretroviral drugs to reduce the risk of transmission (when the infected person takes the medicines; treatment as prevention) or reduce the risk of acquisition (when the seronegative person takes them; preexposure prophylaxis) have proven to be efficacious. Circumcision of men has also been a major tool relevant for higher prevalence regions such as sub-Saharan Africa. Well-established prevention strategies in the control of sexually transmitted diseases and tuberculosis are highly relevant for HIV (ie, screening, linkage to care, early treatment, and contact tracing). Unfortunately, only slow progress is being made in some available HIV-prevention strategies such as family planning for HIV-infected women who do not want more children and prevention of mother-to-child HIV transmission. Current studies seek to integrate strategies into approaches that combine biomedical, behavioral, and structural methods to achieve prevention synergies. This review identifies the major biomedical approaches demonstrated to be efficacious that are now available. We also highlight the need for behavioral risk reduction and adherence as essential components of any biomedical approach.

Clinical impact and cost-effectiveness of expanded voluntary HIV testing in India

Background

Despite expanding access to antiretroviral therapy (ART), most of the estimated 2.3 to 2.5 million HIV-infected individuals in India remain undiagnosed. The questions of whom to test for HIV and at what frequency remain unclear.

Methods

We used a simulation model of HIV testing and treatment to examine alternative HIV screening strategies: 1) current practice, 2) one-time, 3) every five years, and 4) annually; and we applied these strategies to three population scenarios: 1) the general Indian population (“national population”), i.e. base case (HIV prevalence 0.29%; incidence 0.032/100 person-years [PY]); 2) high-prevalence districts (HIV prevalence 0.8%; incidence 0.088/100 PY), and 3) high-risk groups (HIV prevalence 5.0%; incidence 0.552/100 PY). Cohort characteristics reflected Indians reporting for HIV testing, with a median age of 35 years, 66% men, and a mean CD4 count of 305 cells/µl. The cost of a rapid HIV test was $3.33. Outcomes included life expectancy, HIV-related direct medical costs, incremental cost-effectiveness ratios (ICERs), and secondary transmission benefits. The threshold for “cost-effective” was defined as 3x the annual per capita GDP of India ($3,900/year of life saved [YLS]), or for “very cost-effective” was <1x the annual per capita GDP ($1,300/YLS).

Results

Compared to current practice, one-time screening was very cost-effective in the national population (ICER: $1,100/YLS), high-prevalence districts (ICER: $800/YLS), and high-risk groups (ICER: $800/YLS). Screening every five years in the national population (ICER: $1,900/YLS) and annual screening in high-prevalence districts (ICER: $1,900/YLS) and high-risk groups (ICER: $1,800/YLS) were also cost-effective. Results were most sensitive to costs of care and linkage-to-care.

Conclusions

In India, voluntary HIV screening of the national population every five years offers substantial clinical benefit and is cost-effective. Annual screening is cost-effective among high-risk groups and in high-prevalence districts nationally. Routine HIV screening in India should be implemented.

Patching a leaky pipe: the cascade of HIV care

PURPOSE OF REVIEW

We reviewed recent literature on the cascade of HIV care from HIV testing to suppression of viral load, which has emerged as a critical focus as HIV treatment programs have scaled up.

RECENT FINDINGS

In low- and middle-income countries, HIV testing and diagnosis of people living with HIV (PLHIV), although rapidly expanding, are generally relatively low. Linkage and retention in care are global challenges, with substantial attrition between diagnosis, laboratory or clinical staging, and antiretroviral therapy (ART) initiation, and additional substantial attrition on ART due to loss to follow-up and death. ART coverage is rapidly expanding but is still relatively low, especially when considered as a percentage of all PLHIV. Adherence is also suboptimal and virological suppression is incomplete.

SUMMARY

Taken together, the attrition at each step of the cascade of care results in overall low levels of viral load suppression in the total population of PLHIV. More robust monitoring from the facility to global levels and implementation of established and emerging interventions are needed at each step of the cascade to enhance HIV diagnosis, linkage to and retention in care, ART use, and adherence, and ultimately reduce viral load, improve clinical outcomes, and reduce HIV transmission.

Cost-effectiveness of World Health Organization 2010 guidelines for prevention of mother-to-child HIV transmission in Zimbabwe

BACKGROUND

In 2010, the World Health Organization (WHO) released revised guidelines for prevention of mother-to-child human immunodeficiency virus (HIV) transmission (PMTCT). We projected clinical impacts, costs, and cost-effectiveness of WHO-recommended PMTCT strategies in Zimbabwe.

METHODS

We used Zimbabwean data in a validated computer model to simulate a cohort of pregnant, HIV-infected women (mean age, 24 years; mean CD4 count, 451 cells/µL; subsequent 18 months of breastfeeding). We simulated guideline-concordant care for 4 PMTCT regimens: single-dose nevirapine (sdNVP); WHO-recommended Option A, WHO-recommended Option B, and Option B+ (lifelong maternal 3-drug antiretroviral therapy regardless of CD4). Outcomes included maternal and infant life expectancy (LE) and lifetime healthcare costs (2008 US dollars [USD]). Incremental cost-effectiveness ratios (ICERs, in USD per year of life saved [YLS]) were calculated from combined (maternal + infant) discounted costs and LE.

RESULTS

Replacing sdNVP with Option A increased combined maternal and infant LE from 36.97 to 37.89 years and would reduce lifetime costs from $5760 to $5710 per mother-infant pair. Compared with Option A, Option B further improved LE (38.32 years), and saved money within 4 years after delivery ($5630 per mother-infant pair). Option B+ (LE, 39.04 years; lifetime cost, $6620 per mother-infant pair) improved maternal and infant health, with an ICER of $1370 per YLS compared with Option B.

CONCLUSIONS

Replacing sdNVP with Option A or Option B will improve maternal and infant outcomes and save money; Option B increases health benefits and decreases costs compared with Option A. Option B+ further improves maternal outcomes, with an ICER (compared with Option B) similar to many current HIV-related healthcare interventions.

Behavioral and biomedical combination strategies for HIV prevention

Around 2.5 million people become infected with HIV each year. This extraordinary toll on human life and public health worldwide will only be reversed with effective prevention. What's more, in the next few years, it is likely at least, that no single prevention strategy will be sufficient to contain the spread of the disease. There is a need for combination prevention as there is for combination treatment, including biomedical, behavioral, and structural interventions. Expanded HIV prevention must be grounded in a systematic analysis of the epidemic's dynamics in local contexts. Although 85% of HIV is transmitted sexually, effective combinations of prevention have been shown for people who inject drugs. Combination prevention should be based on scientifically derived evidence, with input and engagement from local communities that fosters the successful integration of care and treatment.

Transitioning HIV care and treatment programs in southern Africa to full local management

Global AIDS programs such as the US President's Emergency Plan for AIDS Relief (PEPFAR) face a challenging health care management transition. HIV care must evolve from vertically-organized, externally-supported efforts to sustainable, locally controlled components that are integrated into the horizontal primary health care systems of host nations. We compared four southern African nations in AIDS care, financial, literacy, and health worker capacity parameters (2005 to 2009) to contrast in their capacities to absorb the huge HIV care and prevention endeavors that are now managed with international technical and fiscal support. Botswana has a relatively high national income, a small population, and an advanced HIV/AIDS care program; it is well poised to take on management of its HIV/AIDS programs. South Africa has had a slower start, given HIV denialism philosophies of the previous government leadership. Nonetheless, South Africa has the national income, health care management, and health worker capacity to succeed in fully local management. The sheer magnitude of the burden is daunting, however, and South Africa will need continuing fiscal assistance. In contrast, Zambia and Mozambique have comparatively lower per capita incomes, many fewer health care workers per capita, and lower national literacy rates. It is improbable that fully independent management of their HIV programs is feasible on the timetable being contemplated by donors, nor is locally sustainable financing conceivable at present. A tailored nation-by-nation approach is needed for the transition to full local capacitation; donor nation policymakers must ensure that global resources and technical support are not removed prematurely.

The cost-effectiveness of pre-exposure prophylaxis for HIV infection in South African women

BACKGROUND

Recent trials report the short-term efficacy of tenofovir-based pre-exposure prophylaxis (PrEP) for prevention of human immunodeficiency virus (HIV) infection. PrEP's long-term impact on patient outcomes, population-level transmission, and cost-effectiveness remains unknown.

METHODS

We linked data from recent trials to a computer model of HIV acquisition, screening, and care to project lifetime HIV risk, life expectancy (LE), costs, and cost-effectiveness, using 2 PrEP-related strategies among heterosexual South African women: (1) women receiving no PrEP and (2) women not receiving PrEP (a tenofovir-based vaginal microbicide). We used a South African clinical cohort and published data to estimate population demographic characteristics, age-adjusted incidence of HIV infection, and HIV natural history and treatment parameters. Baseline PrEP efficacy (percentage reduction in HIV transmission) was 39% at a monthly cost of $5 per woman. Alternative parameter values were examined in sensitivity analyses.

RESULTS

Among South African women, PrEP reduced mean lifetime HIV risk from 40% to 27% and increased population discounted (undiscounted) LE from 22.51 (41.66) to 23.48 (44.48) years. Lifetime costs of care increased from $7280 to $9890 per woman, resulting in an incremental cost-effectiveness ratio of $2700/year of life saved, and may, under optimistic assumptions, achieve cost savings. Under baseline HIV infection incidence assumptions, PrEP was not cost saving, even assuming an efficacy >60% and a cost <$1. At an HIV infection incidence of 9.1%/year, PrEP achieved cost savings at efficacies ≥50%.

CONCLUSIONS

PrEP in South African women is very cost-effective by South African standards, conferring excellent value under virtually all plausible data scenarios. Although optimistic assumptions would be required to achieve cost savings, these represent important benchmarks for future PrEP study design.

Opportunities and challenges for cost-efficient implementation of new point-of-care diagnostics for HIV and tuberculosis

Stakeholders agree that supporting high-quality diagnostics is essential if we are to continue to make strides in the fight against human immunodeficiency virus (HIV) and tuberculosis. Despite the need to strengthen existing laboratory infrastructure, which includes expanding and developing new laboratories, there are clear diagnostic needs where conventional laboratory support is insufficient. Regarding HIV, rapid point-of-care (POC) testing for initial HIV diagnosis has been successful, but several needs remain. For tuberculosis, several new diagnostic tests have recently been endorsed by the World Health Organization, but a POC test remains elusive. Human immunodeficiency virus and tuberculosis are coendemic in many high prevalence locations, making parallel diagnosis of these conditions an important consideration. Despite its clear advantages, POC testing has important limitations, and laboratory-based testing will continue to be an important component of future diagnostic networks. Ideally, a strategic deployment plan should be used to define where and how POC technologies can be most efficiently and cost effectively integrated into diagnostic algorithms and existing test networks prior to widespread scale-up. In this fashion, the global community can best harness the tremendous capacity of novel diagnostics in fighting these 2 scourges.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Suboptimal patterns of provider initiated HIV testing and counselling, antiretroviral therapy eligibility assessment and referral in primary health clinic attendees in Blantyre, Malawi

Objective

To understand reasons for suboptimal and delayed uptake of antiretroviral therapy (ART) by describing the patterns of HIV testing and counselling (HTC) and outcomes of ART eligibility assessments in primary clinic attendees.

Methods

All clinic attendances and episodes of HTC were recorded at two clinics in Blantyre. A cohort of newly diagnosed HIV-positive adults (>15 years) was recruited and exit interviews undertaken. Logistic regression models were constructed to investigate factors associated with referral to start ART. Qualitative interviews were conducted with providers and patients.

Results

There were 2398 episodes of HTC during 18 021 clinic attendances (13.3%) between January and April 2011. The proportion of clinic attendees undergoing HTC was lowest in non-pregnant women (6.3%) and men (8.5%), compared with pregnant women (47.2%). Men had more advanced HIV infection than women (79.7% WHO stage 3 or 4 vs. 56.4%). Problems with WHO staging and access to CD4 counts affected ART eligibility assessments; only 48% completed ART eligibility assessment, and 54% of those reporting WHO stage 3/4 illnesses were not referred to start ART promptly. On multivariate analysis, HIV-positive pregnant women were significantly less likely to be referred directly for ART initiation (adjusted OR: 0.29, 95% CI: 0.13–0.63).

Conclusions

These data show that provider-initiated testing and counselling (PITC) has not yet been fully implemented at primary care clinics. Suboptimal ART eligibility assessments and referral (reflecting the difficulties of WHO staging in primary care) mean that simplified eligibility assessment tools are required to reduce unnecessary delay and attrition in the pre-ART period. Simplified initiation criteria for pregnant women, as being introduced in Malawi, should improve linkage to ART.

HIV self-testing and the missing linkage

Rochelle Walensky and Ingrid Bassett discuss new research in <I>PLoS Medicine</I> that assessed the feasibility of home-based oral HIV self-testing in Malawi, and suggest that linkage to care must be demonstrated before the success of oral self-testing can be determined.

High prevalence of self-reported undiagnosed HIV despite high coverage of HIV testing: a cross-sectional population based sero-survey in South Africa

Objectives

To measure HIV prevalence and uptake of HIV counseling and testing (HCT) in a peri-urban South African community. To assess predictors for previous HIV testing and the association between the yield of previously undiagnosed HIV and time of last negative HIV test

Methods

A random sample of 10% of the adult population (≥15 years) were invited to attend a mobile HCT service. Study procedures included a questionnaire, HIV testing and CD4 counts. Predictors for previous testing were determined using a binominal model.

Results

1,144 (88.0%) of 1,300 randomly selected individuals participated in the study. 71.0% (68.3–73.6) had previously had an HIV test and 37.5% (34.6–40.5) had tested in the past 12 months. Men, migrants and older (>35 years) and younger (<20 years) individuals were less likely to have had a previous HIV test. Overall HIV prevalence was 22.7 (20.3–25.3) with peak prevalence of 41.8% (35.8–47.8) in women aged 25.1–35 years and 37.5% (26.7–48.3) in men aged 25.1–45 years. Prevalence of previously undiagnosed HIV was 10.3% (8.5–12.1) overall and 4.5% (2.3–6.6), 8.0% (CI 3.9–12.0) and 20.0% (13.2–26.8) in individuals who had their most recent HIV test within 1, 1–2 and more than 2 years prior to the survey.

Conclusion

The high burden of undiagnosed HIV in individuals who had recently tested underscores the importance of frequent repeat testing at least annually. The high prevalence of previously undiagnosed HIV in individuals reporting a negative test in the 12 months preceding the survey indicates a very high incidence. Innovative prevention strategies are needed.

HIV prevention transformed: the new prevention research agenda

We have entered a new era in HIV prevention whereby priorities have expanded from biomedical discovery to include implementation, effectiveness, and the effect of combination prevention at the population level. However, gaps in knowledge and implementation challenges remain. In this Review we analyse trends in the rapidly changing landscape of HIV prevention, and chart a new path for HIV prevention research that focuses on the implementation of effective and efficient combination prevention strategies to turn the tide on the HIV pandemic.

A cost-effectiveness analysis of alternative HIV retesting strategies in sub-saharan Africa

BACKGROUND

Guidelines in sub-Saharan Africa on when HIV-seronegative persons should retest range from never to annually for lower-risk populations and from annually to every 3 months for high-risk populations.

METHODS

We designed a mathematical model to compare the cost-effectiveness of alternative HIV retesting frequencies. Cost of HIV counseling and testing, linkage to care, treatment costs, disease progression, and mortality, and HIV transmission are modeled for three hypothetical cohorts with posited annual HIV incidence of 0.8%, 1.3%, and 4.0%, respectively. The model compared costs, quality-adjusted life-years gained, and secondary infections averted from testing intervals ranging from 3 months to 30 years. Input parameters from sub-Saharan Africa were used and explored in sensitivity analyses.

RESULTS

Accounting for secondary infections averted, the most cost-effective testing frequency was every 7.5 years for 0.8% incidence, every 5 years for 1.3% incidence, and every 2 years for 4.0% incidence. Optimal testing strategies and their relative cost-effectiveness were most sensitive to assumptions about HIV counseling and testing and treatment costs, rates of CD4 decline, rates of HIV transmission, and whether tertiary infections averted were taken into account.

CONCLUSIONS

While higher risk populations merit more frequent HIV testing than low risk populations, regular retesting is beneficial even in low-risk populations. Our data demonstrate benefits of tailoring testing intervals to resource constraints and local HIV incidence rates.