Examining the promise of HIV elimination by 'test and treat' in hyperendemic settings

Assessing index CD4 and associated outcomes at 1-year in a tertiary HIV clinic, KwaZulu-Natal

BACKGROUND

 Human immunodeficiency virus (HIV) management guidelines have evolved from initiating therapy at CD4 counts of ≤ 200 cells/m3 to implementing universal test and treat (UTT). This study aimed to assess whether in clinical practice, patients are presenting with higher baseline CD4 counts, describe the incidence of opportunistic infections and the proportion that achieved viral suppression.

METHODS

 A retrospective cohort design with convenience sampling was conducted. Cohort 1 included patients initiated on antiretroviral therapy (ART) between 01 January 2014 and 31 December 2014, when criteria were set at CD4 count ≤ 350 cells/mm3. Cohort 2 included patients initiated on ART between 01 January 2019 and 31 December 2019, during the UTT era.

RESULTS

 At ART initiation, the median CD4 cell was 170 cells/mm3 (interquartile range [IQR]: 85.5-287) in Cohort 1 cells/mm3 and 243 cells/mm3 (IQR: 120-411) in Cohort 2. Tuberculosis was the predominant OI in the group with CD4 cell count ≤ 200 cells/m3 in both Cohort 1 (26.8%) and Cohort 2 (27.9%), p = 0.039. At 1 year, virological suppression was achieved in only 77.7% and 84.7% of Cohorts 1 and 2 patients.

CONCLUSION

 A notable portion of patients at King Edward VIII Hospital's HIV clinic commenced ART with CD4 counts significantly below the recommended guideline thresholds.Contribution: The research revealed a delay in initiating ART. A comprehensive reevaluation is essential to pinpoint the factors contributing to this delay and to devise customised interventions.

Determinants of Preexposure Prophylaxis Cascade Among Sexual and Gender Minorities in Nigeria

BACKGROUND

Preexposure prophylaxis (PrEP) is effective in preventing human immunodeficiency virus (HIV) infection among sexual and gender minorities (SGMs). We evaluated the characteristics associated with engagement in 7 steps of the PrEP cascade among SGMs in Nigeria.

METHODS

Sexual and gender minorities without HIV from the Abuja site of TRUST/RV368 cohort who were surveyed on awareness of and willingness to use PrEP were approached for PrEP initiation upon availability of oral daily PrEP. To understand gaps in the uptake of oral daily PrEP, we categorized the HIV PrEP cascade as (i) education about PrEP, (ii) interest in PrEP, (iii) successful contact, (iv) appointment scheduled, (v) appointment attendance, (vi) PrEP initiation, and (vii) plasma protective levels of tenofovir disoproxil fumarate. Multivariable logistic regression models were used to determine factors associated with each of the 7 steps in the HIV PrEP cascade.

RESULTS

Of 788 participants, 718 (91.1%) showed interest in taking oral daily PrEP every day and/or after a sexual act, 542 (68.8%) were successfully contacted, 433 (54.9%) scheduled an appointment, 409 (51.9%) attended a scheduled appointment, 400 (50.8%) initiated oral daily PrEP, and 59 (7.4%) had protective levels of tenofovir disoproxil fumarate. Of initiators of PrEP, 23 (5.8%) seroconverted at a rate of 13.9 cases/100 person-years. Better social support, larger network density, and higher education were associated with engagement in 4 to 5 components of the cascade.

CONCLUSIONS

Our data highlight a gap between willingness and actual PrEP use. Despite PrEP's effectiveness in preventing HIV, the optimal impact of PrEP for SGMs in sub-Saharan Africa will require multifaceted approaches that combine social support, education, and destigmatization.

Guidance on the use of complex systems models for economic evaluations of public health interventions

To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to develop and jointly write guidance for the use of complex systems models for health economic analysis. The content of workshops was informed by a scoping review. A public health complex systems model for economic evaluation is defined as a quantitative, dynamic, non-linear model that incorporates feedback and interactions among model elements, in order to capture emergent outcomes and estimate health, economic and potentially other consequences to inform public policies. The guidance covers: when complex systems modeling is needed; principles for designing a complex systems model; and how to choose an appropriate modeling technique. This paper provides a definition to identify and characterize complex systems models for economic evaluations and proposes guidance on key aspects of the process for health economics analysis. This document will support the development of complex systems models, with impact on public health systems policy and decision making.

Exploring the impacts of and reactions to HIV diagnosis in older adults: narratives from Ga-Rankuwa, South Africa

There is an increase in prevalence of human immunodeficiency virus (HIV) infection among older adults. This new emerging social group is being overlooked, owing to the focus on groups that have traditionally been regarded as "high risk". This article set out to explore the impact of and reaction to HIV infection among older adults at the point of diagnosis. This study used a qualitative exploratory design that included a purposive sample of older adults currently receiving HIV treatment. The researchers recruited 12 participants who met the study's inclusion criteria. Face-to-face interviews were used to collect data. A thematic approach was used to analyse the data. The study found that the impact on and reaction of older adults following HIV diagnosis included anger and shock, feeling suicidal, blaming others, fear of stigma and discrimination, loss of trust and intimacy, fear of disclosure to new partners and denial. The study concluded that there is a need to improve sexual health and HIV services that cater for the needs of older adults as a new emerging group affected by HIV. Furthermore, HIV testing and prevention counselling should be offered to older adults just as it is to younger patients.

Risk heterogeneity in compartmental HIV transmission models of ART as prevention in Sub-Saharan Africa: A scoping review

BACKGROUND

Transmission models provide complementary evidence to clinical trials about the potential population-level incidence reduction attributable to ART (ART prevention impact). Different modelling assumptions about risk heterogeneity may influence projected ART prevention impacts. We sought to review representations of risk heterogeneity in compartmental HIV transmission models applied to project ART prevention impacts in Sub-Saharan Africa.

METHODS

We systematically reviewed studies published before January 2020 that used non-linear compartmental models of sexual HIV transmission to simulate ART prevention impacts in Sub-Saharan Africa. We summarized data on model structure/assumptions (factors) related to risk and intervention heterogeneity, and explored multivariate ecological associations of ART prevention impacts with modelled factors.

RESULTS

Of 1384 search hits, 94 studies were included. 64 studies considered sexual activity stratification and 39 modelled at least one key population. 21 studies modelled faster/slower ART cascade transitions (HIV diagnosis, ART initiation, or cessation) by risk group, including 8 with faster and 4 with slower cascade transitions among key populations versus the wider population. In ecological analysis of 125 scenarios from 40 studies (subset without combination intervention), scenarios with risk heterogeneity that included turnover of higher risk groups were associated with smaller ART prevention benefits. Modelled differences in ART cascade across risk groups also influenced the projected ART benefits, including: ART prioritized to key populations was associated with larger ART prevention benefits. Of note, zero of these 125 scenarios considered lower ART coverage among key populations.

CONCLUSION

Among compartmental transmission models applied to project ART prevention impacts in Sub-Saharan Africa, representations of risk heterogeneity and projected impacts varied considerably. Inclusion/exclusion of risk heterogeneity with turnover, and intervention heterogeneity across risk groups could influence the projected impacts of ART scale-up. These findings highlight a need to capture risk heterogeneity with turnover and cascade heterogeneity when projecting ART prevention impacts.

Experiences of new diagnoses among HIV-positive persons: implications for public health

Background

Ready acceptance of experiences of new diagnoses among HIV-positive persons is a known personal and public health safety-net. Its beneficial effects include prompt commencement and sustenance of HIV-positive treatment and care, better management of transmission risk, and disclosure of the HIV-positive status to significant others. Yet, no known study has explored this topic in Ghana; despite Ghana’s generalised HIV/AIDS infection rate. Existing studies have illuminated the effects of such reactions on affected significant others; not the infected.

Methods

This paper studied qualitatively the experiences of new diagnoses among 26 persons living with HIV/AIDS. Sample selection was random, from two hospitals in a district in Ghana heavily affected by HIV/AIDS. The paper applied the Hopelessness Theory of Depression.

Results

As expected, the vast majority of respondents experienced the new diagnoses of their HIV-positive infection with a myriad of negative psychosocial reactions, including thoughts of committing suicide. Yet, few of them received the news with resignation. For the vast majority of respondents, having comorbidities from AIDS prior to the diagnosis primarily shaped their initial reactions to their diagnosis. The respondents’ transitioning to self-acceptance of their HIV-positive status was mostly facilitated by receiving counselling from healthcare workers.

Conclusions

Although the new HIV-positive diagnosis was immobilising to most respondents, the trauma faded, paving the way for beneficial public health actions. The results imply the critical need for continuous education on HIV/AIDS by public health advocates, using mass media, particularly, TV. Healthcare workers in VCTs should empathise with persons who experience new diagnoses of their HIV-positive status.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-12809-6.

HIV incidence, viremia, and the national response in Eswatini: Two sequential population-based surveys

With the highest HIV incidence and prevalence globally, the government of Eswatini started a substantial scale-up of HIV treatment and prevention services in 2011. Two sequential large population-based surveys were conducted before and after service expansion to assess the impact of the national response. Cross-sectional, household-based, nationally representative samples of adults, ages 18 to 49 years, were sampled in 2011 and 2016. We measured HIV prevalence, incidence (recent infection based on limiting antigen ≤1.5 optical density units and HIV RNA ≥1000 copies/mL), viral load suppression (HIV RNA <1000 copies/mL among all seropositive adults) and unsuppressed viremia (HIV RNA ≥1000 copies/mL among all, regardless of HIV status) and assessed for temporal changes by conducting a trend analysis of the log ratio of proportions, using a Z statistic distribution. HIV prevalence remained stable from 2011 to 2016 [32% versus 30%, p = 0.10]. HIV incidence significantly declined 48% [2.48% versus 1.30%, p = 0.01]. Incidence remained higher among women than men [2011: 3.16% versus 1.83%; 2016: 1.76% versus 0.86%], with a smaller but significant relative reduction among women [44%; p = 0.04] than men [53%; p = 0.09]. The proportion of seropositive adults with viral load suppression significantly increased from 35% to 71% [p < .001]. The proportion of the total adult population with unsuppressed viremia decreased from 21% to 9% [p < .001]. National HIV incidence in Eswatini decreased by nearly half and viral load suppression doubled over a five-year period. Unsuppressed viremia in the total population decreased 58%. These population-based findings demonstrate the national impact of expanded HIV services in a hyperendemic country.

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.

Substance Use Stigma, Avoidance Coping, and Missed HIV Appointments Among MSM Who Use Substances

Men who have sex with men (MSM) living with HIV who use substances have multiple stigmatized identities. Theory suggests that internalization of stigma may elicit avoidance behaviors associated with these stigmas, potentially resulting in suboptimal engagement in HIV care. We investigated interrelationships between internalized stigmas related to HIV, sexual orientation, and substance use; avoidance coping; and missed HIV appointments among 202 MSM living with HIV who use substances. Neither HIV nor sexual orientation-related internalized stigmas were associated with missed appointments, however, internalized substance use stigma (SUS) was associated (OR 1.47, 95% CI 1.15, 1.87). The relationship between internalized SUS and missed appointments was partially accounted for by avoidance coping (b = 0.12; bootstrap 95% CI 0.02, 0.25). To better understand the role of SUS, we assessed relationships between enacted and anticipated SUS and missed appointments (OR 2.08, 95% CI 1.52, 2.84 and OR 1.44, 95% CI 1.10, 1.88, respectively). Avoidance coping fully accounted for the relationship between anticipated SUS and missed appointments (b = 0.12; 95% CI 0.02, 0.25). Results suggest that avoidance strategies to manage anticipated SUS may result in substance using MSM forgoing HIV care appointments.

Intersecting internalized stigmas and HIV self-care among men who have sex with men and who use substances

RATIONALE

Men who have sex with men (MSM) are disproportionately affected by HIV, substance use, and stigma related to co-existing or intersecting identities that are stigmatized or devalued by society (e.g., being a sexual minority male, a person living with HIV, or a person who uses substances). Evidence indicates that when stigma is internalized it may act as a barrier to engagement in self-care behaviors.

OBJECTIVE

Gaining a better understanding of how intersecting internalized stigmas affect HIV self-care among MSM who use substances.

METHODS

To investigate these relationships, we conducted semi-structured qualitative interviews until we reached thematic saturation (n = 33) with HIV + MSM who use substances and were sub-optimally engaged in HIV care. Interviews inquired about identity, internalized stigmas, substance use, HIV self-care behaviors, and interrelationships between concepts.

RESULTS

Our sample was 61% African American and 76% reported annual incomes of ≤$20,000. Approximately half of the participants explicitly described how intersecting internalized stigmas impacted their sense of self and their behavior. The overwhelming majority conveyed that internalized stigma related to substance use was the most burdensome and was considered a barrier to HIV self-care behaviors. Participants also described internalized stigmas related to HIV and sexual orientation, as well as race, effeminateness, poverty, and housing instability, which together impacted their psychological wellbeing and HIV self-care.

CONCLUSIONS

Our results indicate a need for clinicians to consider and address intersecting internalized stigmas, particularly internalized stigma related to substance use, to both reduce substance use and improve HIV self-care among MSM who use substances and are sub-optimally engaged in HIV care.

A call for epidemic modeling to examine historical and structural drivers of racial disparities in infectious disease

Since this is a commentary, there is no abstract.

Development and dissemination of infectious disease dynamic transmission models during the COVID-19 pandemic: what can we learn from other pathogens and how can we move forward?

The current COVID-19 pandemic has resulted in the unprecedented development and integration of infectious disease dynamic transmission models into policy making and public health practice. Models offer a systematic way to investigate transmission dynamics and produce short-term and long-term predictions that explicitly integrate assumptions about biological, behavioural, and epidemiological processes that affect disease transmission, burden, and surveillance. Models have been valuable tools during the COVID-19 pandemic and other infectious disease outbreaks, able to generate possible trajectories of disease burden, evaluate the effectiveness of intervention strategies, and estimate key transmission variables. Particularly given the rapid pace of model development, evaluation, and integration with decision making in emergency situations, it is necessary to understand the benefits and pitfalls of transmission models. We review and highlight key aspects of the history of infectious disease dynamic models, the role of rigorous testing and evaluation, the integration with data, and the successful application of models to guide public health. Rather than being an expansive history of infectious disease models, this Review focuses on how the integration of modelling can continue to be advanced through policy and practice in appropriate and conscientious ways to support the current pandemic response.

Using repeated home-based HIV testing services to reach and diagnose HIV infection among persons who have never tested for HIV, Chókwè health demographic surveillance system, Chókwè district, Mozambique, 2014-2017

Background

HIV prevalence in Mozambique (12.6%) is one of the highest in the world, yet ~40% of people living with HIV (PLHIV) do not know their HIV status. Strategies to increase HIV testing uptake and diagnosis among PLHIV are urgently needed. Home-based HIV testing services (HBHTS) have been evaluated primarily as a 1-time campaign strategy. Little is known about the potential of repeating HBHTS to diagnose HIV infection among persons who have never been tested (NTs), nor about factors/reasons associated with never testing in a generalized epidemic setting.

Methods

During 2014–2017, counselors visited all households annually in the Chókwè Health and Demographic Surveillance System (CHDSS) and offered HBHTS. Cross-sectional surveys were administered to randomly selected 10% or 20% samples of CHDSS households with participants aged 15–59 years before HBHTS were conducted during the visit. Descriptive statistics and logistic regression were used to assess the proportion of NTs, factors/reasons associated with never having been tested, HBHTS acceptance, and HIV-positive diagnosis among NTs.

Results

The proportion of NTs decreased from 25% (95% confidence interval [CI]:23%–26%) during 2014 to 12% (95% CI:11% –13%), 7% (95% CI:6%–8%), and 7% (95% CI:6%–8%) during 2015, 2016, and 2017, respectively. Adolescent boys and girls and adult men were more likely than adult women to be NTs. In each of the four years, the majority of NTs (87%–90%) accepted HBHTS. HIV-positive yield among NTs subsequently accepting HBHTS was highest (13%, 95% CI:10%–15%) during 2014 and gradually reduced to 11% (95% CI:8%–15%), 9% (95% CI:6%–12%), and 2% (95% CI:0%–4%) during 2015, 2016, and 2017, respectively.

Conclusions

Repeated HBHTS was helpful in increasing HIV testing coverage and identifying PLHIV in Chókwè. In high HIV-prevalence settings with low testing coverage, repeated HBHTS can be considered to increase HIV testing uptake and diagnosis among NTs.

Evidence of sociodemographic heterogeneity across the HIV treatment cascade and progress towards 90-90-90 in sub-Saharan Africa - a systematic review and meta-analysis

Introduction

Heterogeneity of sociodemographics and risk behaviours across the HIV treatment cascade could influence the public health impact of universal ART in sub‐Saharan Africa if those not virologically suppressed are more likely to be part of a risk group contributing to onward infections. Sociodemographic and risk heterogeneity across the treatment cascade has not yet been comprehensively described or quantified and we seek to systematically review and synthesize research on this topic among adults in Africa.

Methods

We conducted a systematic review of peer‐reviewed literature in Embase and MEDLINE databases as well as grey literature sources published in English between 2014 and 2018. We included studies that included people living with HIV (PLHIV) aged ≥15 years, and reported a 90‐90‐90 outcome: awareness of HIV‐positive status, ART use among those diagnosed or viral suppression among those on ART. We summarized measures of association between sociodemographics, within each outcome, and as a composite measure of population‐wide viral suppression.

Results and discussion

From 3533 screened titles, we extracted data from 92 studies (50 peer‐reviewed, 42 grey sources). Of included studies, 32 reported on awareness, 53 on ART use, 32 on viral suppression and 23 on population‐wide viral suppression. The majority of studies were conducted in South Africa, Uganda, and Malawi and reported data for age and gender. When stratified, PLHIV ages 15 to 24 years had lower median achievement of the treatment cascade (60‐49‐81), as compared to PLHIV ≥25 years (70‐63‐91). Men also had lower median achievement of the treatment cascade (66‐72‐85), compared to women (79‐76‐89). For population‐wide viral suppression, women aged ≥45 years had achieved the 73% target, while the lowest medians were among 15‐ to 24‐year‐old men (37%) and women (49%).

Conclusions

Considerable heterogeneity exists by age and gender for achieving the HIV 90‐90‐90 treatment goals. These results may inform delivery of HIV testing and treatment in sub‐Saharan Africa, as targeting youth and men could be a strategic way to maximize the population‐level impact of ART.

High specificity of OraQuick® rapid HIV-1/2 antibody testing during dengue infection

BACKGROUND

OraQuick® is a rapid test with high specificity demonstrated in non-dengue endemic settings. However, reports of false positive OraQuick® results suggest poor specificity in the context of dengue fever.

OBJECTIVES

To assess the specificity of OraQuick® for HIV-1/2 in patients with dengue fever.

STUDY DESIGN

In a study performed across two Singapore hospitals, adult participants meeting WHO 2009 criteria for probable dengue (fever >37.5 °C plus two other clinical or haematological criteria) were identified at hospital outpatient clinics from April 2012 to July 2013. Eligible participants were asked for informed consent to complete a questionnaire on HIV risk factors, as well as HIV testing by OraQuick®, fourth-generation EIA and NAAT. Dengue testing was by Dengue Duo NS1Ag + Ab Combo kits. Confirmed dengue was defined as NS1-positive and probable dengue as IgM-positive.

RESULTS

Of 152 eligible patients, 82 consented to inclusion in the study. Fifty-two of these had dengue; 43 confirmed and 9 probable cases. All patients with dengue had a negative OraQuick® result, negative EIA and undetectable HIV-1 RNA, corresponding to a specificity of 100 %.

CONCLUSIONS

OraQuick® has high specificity in the context of dengue infection. It can be used to diagnose HIV-associated illness as a cause of fever in dengue endemic settings.

Insights into the antiviral activity of phospholipases A2 (PLA2s) from snake venoms

Viruses are associated with several human diseases that infect a large number of individuals, hence directly affecting global health and economy. Owing to the lack of efficient vaccines, antiviral therapy and emerging resistance strains, many viruses are considered as a potential threat to public health. Therefore, researches have been developed to identify new drug candidates for future treatments. Among them, antiviral research based on natural molecules is a promising approach. Phospholipases A₂ (PLA₂s) isolated from snake venom have shown significant antiviral activity against some viruses such as Dengue virus, Human Immunodeficiency virus, Hepatitis C virus and Yellow fever virus, and have emerged as an attractive alternative strategy for the development of novel antiviral therapy. Thus, this review provides an overview of remarkable findings involving PLA₂s from snake venom that possess antiviral activity, and discusses the mechanisms of action mediated by PLA₂s against different stages of virus replication cycle. Additionally, molecular docking simulations were performed by interacting between phospholipids from Dengue virus envelope and PLA₂s from Bothrops asper snake venom. Studies on snake venom PLA₂s highlight the potential use of these proteins for the development of broad-spectrum antiviral drugs.

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.

Integrating Economic Evaluation and Implementation Science to Advance the Global HIV Response

BACKGROUND

Numerous cost-effectiveness analyses have indicated good value for money from a wide array of interventions for treatment and prevention of HIV/AIDS. There is limited evidence, however, regarding how cost-effectiveness information contributes to better decision-making around investment and action in the global HIV response.

METHODS

We review challenges for economic evaluation relevant to the global HIV response and consider how the practice of cost-effectiveness analysis could integrate approaches and insights from implementation science to enhance the impact and efficiency of HIV investments.

RESULTS

In light of signals that cost-effectiveness analyses may be vulnerable to systematic bias toward overly optimistic conclusions, we emphasize two priorities for advancing the field of economic evaluation in HIV/AIDS and more broadly in global health: (1) systematic reevaluation of the cost-effectiveness literature with reference to ex-post empirical evidence on costs and effects in real-world programs and (2) development and adoption of good-practice guidelines for incorporating implementation and delivery aspects into economic evaluations. Toward the latter aim, we propose an integrative approach that focuses on comparative evaluation of strategies, which specify both technologies/interventions as well as the delivery platforms, complementary interventions, and actions needed to increase coverage, quality, and uptake of those technologies/interventions. Specific recommendations draw on several existing implementation science models that provide systematic frameworks for understanding implementation barriers and enablers, designing and choosing specific implementation and policy actions, and evaluating outcomes.

DISCUSSION

These preliminary steps aimed at bridging the divide between economic evaluation and implementation science can help to advance the practice of economic evaluation toward a science of comparative strategy evaluation.

Rapid Initiation of Antiretroviral Therapy Following Diagnosis of Human Immunodeficiency Virus Among Patients with Commercial Insurance Coverage

BACKGROUND

New guidelines for the treatment of human immunodeficiency virus (HIV) advocate for rapid initiation of antiretroviral therapy (ART) ≤ 7 days after HIV diagnosis with agents that have a high genetic barrier to resistance, good tolerability, and convenient dosing.

OBJECTIVE

To describe characteristics, time to ART initiation, and health care costs in commercially insured patients living with HIV in the United States who are treated ≤ 60 days after HIV diagnosis.

METHODS

IBM MarketScan Research Databases (January 1, 2012-December 31, 2017) were used to identify ART-naive adults with HIV-1, ≥ 6 months of continuous eligibility before first HIV diagnosis, and ART initiation ≤ 60 days of first diagnosis. ART regimen had to include a protease inhibitor (PI), an integrase strand transfer inhibitor (INSTI), or a non-nucleoside reverse transcriptase inhibitor (NNRTI) with ≥ 2 nucleoside reverse transcriptase inhibitors. Cohorts were formed based on time to ART initiation after diagnosis: ≤ 7 days or 8-60 days. Health care costs were evaluated at 6, 12, 24, and 36 months after diagnosis among patients with ≥ 36 months of continuous eligibility.

RESULTS

Among 9,351 patients, median time to treatment was 31.0 days. Patients initiating ART > 60 days after HIV diagnosis were excluded (N = 2,608 [27.9%]), while 6,743 (72.1%) initiated ART ≤ 60 days after diagnosis and were analyzed; 18.3% and 81.7% were classified in the ≤ 7 days and 8-60 days cohorts, respectively. For all analyzed patients, mean age was 38.0 (SD = 12.0) years and 13.2% were female; 12.7%, 56.2%, and 31.1% initiated a PI, INSTI, or NNRTI-based regimen, respectively. Elvitegravir (32.9%), efavirenz (20.9%), dolutegravir (18.5%), and darunavir (8.5%) were the most commonly used antiretrovirals; most patients (74.3%) were initiated on single-tablet regimens. PI-based regimens were more common in the ≤ 7 days cohort (PI = 18.1%; darunavir = 11.4%) than in the 8-60 days cohort (PI = 11.5%; darunavir = 7.8%). INSTI-based regimens were more common in the 8-60 days cohort (INSTI = 57.7%; elvitegravir = 33.8%) than in the ≤ 7 days cohort (INSTI = 49.2%; elvitegravir = 29.1%). NNRTI-based regimens were as common in the ≤ 7 days (32.7%) and 8-60 days (30.7%) cohorts. Mean total accumulated costs were lower among patients in the ≤ 7 days cohort than in the 8-60 days cohort at all time points analyzed after diagnosis (e.g., 36 months: ≤ 7 days = $109,456; 8-60 days = $116,870). Total per-patient per-month costs decreased over time in the ≤ 7 days (i.e., 6 months = $4,359; 36 months = $3,040) and 8-60 days cohort (6 months = $4,727; 36 months = $3,246).

CONCLUSIONS

Although 72.1% of patients initiated ART ≤ 60 days after HIV diagnosis, only 18.3% initiated ART ≤ 7 days. Many patients initiating ART ≤ 7 days used suboptimal agents with low rather than high genetic barriers to resistance (i.e., efavirenz and elvitegravir) or agents (dolutegravir) coformulated with other antiretrovirals that require testing to prevent hypersensitivity reactions. Patients in the ≤ 7 days cohort showed lower total health care costs relative to those in the 8-60 days cohort, highlighting the potential long-term benefits of rapid ART initiation.

DISCLOSURES

This study was supported by Janssen Scientific Affairs, which was involved in the study design, interpretation of results, manuscript preparation, and publication decisions. Emond, Lefebvre, Lafeuille, and Côté-Sergent are employees of Analysis Group, a consulting company that was contracted by Janssen Scientific Affairs to conduct this study and develop the manuscript. Benson, Tandon, Chow, and Dunn are employees of Janssen Scientific Affairs and stockholders of Johnson & Johnson. Part of the material in this study has been presented at the AMCP 2019 Annual Meeting; March 25-28, 2019; San Diego, CA.

The costs of home-based HIV testing and counselling in sub-Saharan Africa and its association with testing yield: a literature review

More than 14.5 of the 36.7 million people living with HIV globally do not know their HIV status, making comprehensive testing interventions a critical step in ending the HIV/AIDS epidemic. Home-based testing and counselling (HBTC) involves small teams of community health workers with basic training going from door-to-door and offering services in people's homes. HBTC is effective in reaching individuals that are unlikely to test otherwise, but there is conflicting evidence on its costs and little insight into why estimates are different. We undertook a comparative review of existing costing studies of HBTC in sub-Saharan Africa. Yield or positivity rate, the number of persons tested positive among all tested, is an important metric to judge the efficacy of a testing campaign. We conducted descriptive analyses to test whether unit costs are associated with yield. Studies varied in size with a maximum of 264 953 and a minimum of 494 persons tested. The average "cost per person tested" across 14 studies was $22.8 (SD $14.5) with a minimum of $6 and a maximum of $55.4, and the average "cost per person tested HIV-positive' across 12 studies was $439.4 (SD $399.7) with a minimum of $66.2 and a maximum of $800.9. Correlations between unit cost estimates and yield were not statistically significant. Existant estimates of the costs of HBTC are conflicting, and it is likely that differences in the setting, design and implementation of the studies are responsible for the discrepancies. This makes it difficult to reliably estimate the costs and cost-effectiveness of HBTC.

People don't live on the care cascade: The life of the HIV care cascade as an international AIDS policy and its implications

This article analyses how the HIV care cascade, an analytical tool, has become a policy practice that determines the direction and content of international AIDS policy. It traces the development of the cascade through from its emergence around 2011 to its position framing global AIDS policy by 2018. The article distinguishes between the cascade model as a mapping tool and the care cascade as a policy that aims to end the AIDS epidemic. It then argues that the move from an analytical to a policy tool has important implications, both for the scope of policies and for policy-relevant research. It concludes by considering its implications in determining policy direction. The qualitative research that informs the article is based on published care cascade research and policy documents, and observations of the presentations and discussions at the 2012 and 2018 International AIDS Conferences (IAS). The article uses textual analysis to develop its argument.

Improving the Validity of Mathematical Models for HIV Elimination by Incorporating Empirical Estimates of Progression Through the HIV Treatment Cascade

BACKGROUND

Optimism regarding prospects for eliminating HIV by expanding antiretroviral treatment has been emboldened in part by projections from several mathematical modeling studies. Drawing from a detailed empirical assessment of rates of progression through the entire HIV care cascade, we quantify for the first time the extent to which models may overestimate health benefits from policy changes when they fail to incorporate a realistic understanding of the cascade.

SETTING

Rural KwaZulu-Natal, South Africa.

METHODS

We estimated rates of progression through stages of the HIV treatment cascade using data from a longitudinal population-based HIV surveillance system in rural KwaZulu-Natal. Incorporating empirical estimates in a mathematical model of HIV progression, infection transmission, and care, we estimated life expectancy and secondary infections averted under a range of treatment scale-up scenarios reflecting expanding treatment eligibility thresholds. We compared the results with those implied by the conventional assumptions that have been commonly adopted by existing models.

RESULTS

Survival gains from expanding the treatment eligibility threshold from CD4 350-500 cells/μL and from 500 cells/μL to treating everyone irrespective of their CD4 count may be overestimated by 3.60 and 3.79 times in models that fail to capture realities of the care cascade. HIV infections averted from raising the threshold from CD4 200 to 350, 350 to 500, and 500 cells/μL to treating everyone may be overestimated by 1.10, 2.65, and 1.18 times, respectively.

CONCLUSIONS

Models using conventional assumptions about cascade progression may substantially overestimate health benefits. As implementation of treatment scale-up proceeds, it is important to assess the effects of required scale-up efforts in a way that incorporates empirical realities of how people move through the HIV cascade.

Perfect counterfactuals for epidemic simulations

Simulation studies are often used to predict the expected impact of control measures in infectious disease outbreaks. Typically, two independent sets of simulations are conducted, one with the intervention, and one without, and epidemic sizes (or some related metric) are compared to estimate the effect of the intervention. Since it is possible that controlled epidemics are larger than uncontrolled ones if there is substantial stochastic variation between epidemics, uncertainty intervals from this approach can include a negative effect even for an effective intervention. To more precisely estimate the number of cases an intervention will prevent within a single epidemic, here we develop a 'single-world' approach to matching simulations of controlled epidemics to their exact uncontrolled counterfactual. Our method borrows concepts from percolation approaches, prunes out possible epidemic histories and creates potential epidemic graphs (i.e. a mathematical representation of all consistent epidemics) that can be 'realized' to create perfectly matched controlled and uncontrolled epidemics. We present an implementation of this method for a common class of compartmental models (e.g. SIR models), and its application in a simple SIR model. Results illustrate how, at the cost of some computation time, this method substantially narrows confidence intervals and avoids nonsensical inferences. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'. This theme issue is linked with the earlier issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'.

FROM INDIVIDUAL HEALTH TO COMMUNITY HEALTH: TOWARDS MULTISCALE MODELING OF DIRECTLY TRANSMITTED INFECTIOUS DISEASE SYSTEMS

In this paper, we present a new method for developing a class of nested multiscale models for directly transmitted infectious disease systems that integrates within-host scale and between-host scale using community pathogen load (CPL) as a new public health measure of a community’s level of infectiousness and as an indicator of the effectiveness of health interventions. The approach develops a multiscale modeling science base for directly transmitted infectious disease systems (where the inside-host environment’s biological entities such as cells, tissues, organs, body fluids, whole body are the reservoir of infective pathogen in the community) that is comparable to an existing multiscale modeling science base for environmentally transmitted infectious diseases (where the outside-host geographical environment’s physical entities such as soil, air, formites/contact surfaces, food and water are the reservoir of infective pathogen in the community) where pathogen load in the environment is explicitly incorporated into the model. This is achieved by assuming that infected hosts in the community are homogeneous and unevenly distributed microbial habitats. We illustrate the utility of this multiscale modeling methodology by evaluating the comparative effectiveness of HIV/AIDS preventive and treatment interventions as a case study.

Conflict and accord of optimal treatment strategies for HIV infection within and between hosts

Most of previous studies investigated the optimal control of HIV infection at either within-host or between-host level. However, the optimal treatment strategy for the individual may not be optimal for the population and vice versa. To determine when the two-level optimal controls are in accord or conflict, we develop a multi-scale model using various functions that link the viral load within host and the transmission rate between hosts, calibrated by cohort data. We obtain the within-host optimal treatment scheme that minimizes the viral load and maximizes the count of healthy cells at the individual level, and the coupled optimal scheme that minimizes the basic reproduction number at the population level. Mathematical analysis shows that whether the two-level optimal controls coincide depends on the sign of the product of their switching functions. Numerical results suggest that they are in accord for a high maximal drug efficacy but may conflict for a low drug efficacy. Using the multi-scale model, we also identify a threshold of the treatment effectiveness that determines how early treatment initiation can affect the disease dynamics among population. These results may help develop a synergistic treatment protocol beneficial to both HIV-infected individuals and the whole population.

Evaluating the Integrated Methadone and Anti-Retroviral Therapy Strategy in Tanzania Using the RE-AIM Framework

There are an estimated 50,000 people who inject drugs in Tanzania, with an HIV prevalence in this population of 42%. The Integrated Methadone and Anti-Retroviral Therapy (IMAT) strategy was developed to integrate HIV services into an opioid treatment program (OTP) in sub-Saharan Africa and increase anti-retroviral therapy (ART) initiation rates. In this paper, we evaluate the IMAT strategy using an implementation science framework to inform future care integration efforts in the region. IMAT centralized HIV services into an OTP clinic in Dar Es Salaam, Tanzania: HIV diagnosis, ART initiation, monitoring and follow up. A mixed-methods, concurrent design, was used for evaluation: quantitative programmatic data and semi-structured interviews with providers and clients addressed 4 out of 5 components of the RE-AIM framework: reach, effectiveness, adoption, implementation. Results showed high reach: 98% of HIV-positive clients received HIV services; effectiveness: 90-day ART initiation rate doubled, from 41% pre-IMAT to 87% post-IMAT (p < 0.001); proportion of HIV-positive eligible clients on ART increased from 71% pre-IMAT to 98% post-IMAT (p < 0.001). There was high adoption and implementation protocol fidelity. Qualitative results informed barriers and facilitators of RE-AIM components. In conclusion, we successfully integrated HIV care into an OTP clinic in sub-Saharan Africa with increased rates of ART initiation. The IMAT strategy represents an effective care integration model to improve HIV care delivery for OTP clients.

Retention on antiretroviral therapy during Universal Test and Treat implementation in Zomba district, Malawi: a retrospective cohort study

INTRODUCTION

Since June 2016, the national HIV programme in Malawi has adopted Universal Test and Treat (UTT) guidelines requiring that all persons who test HIV positive will be referred to start antiretroviral therapy (ART). Although there is strong evidence from clinical trials that early initiation of ART leads to reduced morbidity and mortality, the impact of UTT on retention on ART in real-life programmatic settings in Africa is not yet known.

METHODS

We conducted a retrospective cohort study in Zomba district, Malawi to compare ART outcomes of patients who initiated ART under 2016 UTT guidelines and those who started ART prior to rollout of UTT (pre-UTT). We analysed data from 32 rural and urban health facilities of various sizes. Cox proportional hazards modelling was used to determine the independent risk factors of attrition from ART at 12 months. All analyses were adjusted for clustering by health facility using a robust standard errors approach.

RESULTS

Among 1492 patients (mean age 34.4 years, 933 (63%) female) who initiated ART during the study period, 501 were enrolled in the pre-UTT cohort and 911 during UTT. At 12 months, retention on ART in the UTT cohort was higher than in the pre-UTT cohort 83.0% (95% confidence interval (CI): 81.0% to 85.0%) versus 76.2% (95% CI 73.9% to 78.5%). Adolescents, aged 10 to 19 years (adjusted hazard ratio (aHR) 1.53; 95% CI 1.01 to 2.32), and women who were pregnant or breastfeeding at ART initiation (aHR 1.87; 95% CI 1.30 to 2.38) were at higher risk of attrition in the combined pre-UTT and UTT cohort.

CONCLUSIONS

Retention on ART was nearly 6% higher after UTT introduction. Young adults and women who were pregnant or breastfeeding at the start of ART were at increased risk of attrition, emphasizing the need for targeted interventions for these groups to achieve the 90-90-90 UNAIDS targets in the UTT era.

Health Workers' Perspectives on the Outcomes, Enablers, and Barriers to the Implementation of HIV "Test and Treat" Guidelines in Abuja, Nigeria

We evaluated health workers' perspectives on the implementation of the 2016 HIV "Test and Treat" guidelines in Nigeria. Using semi-structured interviews, qualitative data was collected from twenty health workers meeting inclusion criteria in six study sites. Data exploration was conducted using thematic content analysis. Participants perceived that the "Test and Treat" guidelines improved care for PLHIV, though they also perceived possible congested clinics. Perceived key factors enabling guidelines use were perceived patient benefits, availability of policy document and trainings. Perceived key barriers to guidelines use were poverty among patients, inadequate human resources and stock-outs of HIV testing kits. Further improvements in uptake of guidelines could be achieved by effecting an efficient supply chain system for HIV testing kits, and improved guidelines distribution and capacity building prior to implementation. Additionally, implementing differentiated approaches that decongest clinics, and programs that economically empower patients, could improve guidelines use, as Nigeria scales "Test and Treat" nationwide.

Improving PrEP Implementation Through Multilevel Interventions: A Synthesis of the Literature

There are many challenges to accessing PrEP and thus low uptake in the United States. This review (2007–2017) of PrEP implementation identified barriers to PrEP and interventions to match those barriers. The final set of articles (n = 47) included content on cognitive aspects of HIV service providers and individuals at risk for infection, reviews, and case studies. Cognitive barriers and interventions regarding patients and providers included knowledge, attitudes, and beliefs about PrEP. The “purview paradox” was identified as a key barrier—HIV specialists often do not see HIV-negative patients, while primary care physicians, who often see uninfected patients, are not trained to provide PrEP. Healthcare systems barriers included lack of communication about, funding for, and access to PrEP. The intersection between PrEP-stigma, HIV-stigma, transphobia, homophobia, and disparities across gender, racial, and ethnic groups were identified; but few interventions addressed these barriers. We recommend multilevel interventions targeting barriers at multiple socioecological domains.

Association of Depressive Symptoms with Lapses in Antiretroviral Medication Adherence Among People Living with HIV: A Test of an Indirect Pathway

Viral suppression, a critical component of HIV care, is more likely when individuals initiate antiretroviral therapy (ART) early in disease progression and maintain optimal levels of adherence to ART regimens. Although several studies have documented the negative association of depressive symptoms with ART adherence, less is known about how depressed mood relates to intentional versus unintentional lapses in adherence as well as the mechanisms underlying this association. The purpose of the current study was to examine the association of depressive symptoms with ART adherence, assessed as a multidimensional construct. Secondarily, this study conducted preliminary indirect path models to determine if medication self-efficacy could explain the depressed mood-adherence relationship. Depressive symptoms were not associated with 95% ART taken, self-reported viral load, deliberate adjustments to ART regimens or skipped ART doses. However, the indirect association of depressive symptoms via decrements in medication self-efficacy was significant for 95% ART taken, self-reported viral load and skipped ART doses, but not deliberate changes to ART regimens. In this sample of HIV-positive outpatients, there is evidence to support medication self-efficacy as a potential mechanism underlying the association between depressive symptoms and ART adherence. Additional longitudinal studies are needed to formally examine medication taking self-efficacy as a mediator.

Policy Interventions Shaping HIV Prevention: Providers' Active Role in the HIV Continuum of Care

The U.S. Centers for Disease Control and Prevention (CDC) Diffusion of Effective Behavioral Interventions project has disseminated HIV behavioral interventions (EBIs) across the United States since the 1990s. In 2011, the CDC launched the High-Impact HIV Prevention (HIP) project, providing EBIs plus high-impact services (HIV testing, primary care, and support services). Providers (nurses, social workers, educators) are unable to consistently make linkages; thus, numerous at-risk individuals are not benefitting from HIP. Research on providers' roles in the HIV Continuum of Care-linking clients to HIV testing, primary care, and support services-is lacking. This article helps fill this gap with evidence that providers exposed to EBIs, whose agencies offer EBIs, more frequently link clients to high-impact services. This is based on diffusion of innovations theory, where individuals in social networks influence one another's adoption of innovations. We hypothesize that providers are exposed to EBIs via training, reading and hearing about EBIs, and/or discussing EBIs with colleagues. We used cross-sectional data from 379 providers from 36 agencies in New York City. We used multilevel ordinal logistic regression models to test associations between provider exposure to EBIs (agency provides EBIs) and frequency of linkages to high-impact services. Providers exposed to greater numbers of EBIs more frequently link clients to HIV, hepatitis C (HEP-C), and sexually transmitted infections testing; to primary care; and to drug treatment and mental health services. Providers link clients most frequently to primary care and HIV testing and least frequently to HEP-C testing and syringe exchange. Findings suggest a dose effect, with exposure to more EBIs resulting in more linkages. Findings show a staged, evidence-based prevention approach that includes exposure to EBIs, leading to providers linking clients to high-impact services. There needs to be emphasis on inspiring providers to engage with high-impact services at the elevated levels needed to end the epidemic.

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.

The cost-effectiveness of oral HIV pre-exposure prophylaxis and early antiretroviral therapy in the presence of drug resistance among men who have sex with men in San Francisco

BACKGROUND

Poor adherence to either antiretroviral treatment (ART) or pre-exposure prophylaxis (PrEP) can promote drug resistance, though this risk is thought to be considerably higher for ART. In the population of men who have sex with men (MSM) in San Francisco, PrEP coverage reached 9.6% in 2014 and has continued to rise. Given the risk of drug resistance and high cost of second-line drugs, the costs and benefits of initiating ART earlier while expanding PrEP coverage remain unclear.

METHODS

We develop an infection-age-structured mathematical model and fit this model to the annual incidence of AIDS cases and deaths directly, and to resistance and demographic data indirectly. We investigate the impact of six various intervention scenarios (low, medium, or high PrEP coverage, with or without earlier ART) over the next 20 years.

RESULTS

Low (medium, high) PrEP coverage with earlier ART could prevent 22% (42%, 57%) of a projected 44,508 total new infections and 8% (26%, 41%) of a projected 18,426 new drug-resistant infections, and result in a gain of 43,649 (74,048, 103,270) QALYs over 20 years compared to the status quo, at a cost of $4745 ($78,811, $115,320) per QALY gained, respectively.

CONCLUSIONS

High PrEP coverage with earlier ART is expected to provide the greatest benefit but also entail the highest costs among the strategies considered. This strategy is cost-effective for the San Francisco MSM population, even considering the acquisition and transmission of ART-mediated drug resistance. However, without a substantial increase to San Francisco's annual HIV budget, the most advisable strategy may be initiating ART earlier, while maintaining current strategies of PrEP enrollment.

Using Participatory System Dynamics Modeling to Examine the Local HIV Test and Treatment Care Continuum in Order to Reduce Community Viral Load

Achieving community-level goals to eliminate the HIV epidemic requires coordinated efforts through community consortia with a common purpose to examine and critique their own HIV testing and treatment (T&T) care system and build effective tools to guide their efforts to improve it. Participatory system dynamics (SD) modeling offers conceptual, methodological, and analytical tools to engage diverse stakeholders in systems conceptualization and visual mapping of dynamics that undermine community-level health outcomes and identify those that can be leveraged for systems improvement. We recruited and engaged a 25-member multi-stakeholder Task Force, whose members provide or utilize HIV-related services, to participate in SD modeling to examine and address problems of their local HIV T&T service system. Findings from the iterative model building sessions indicated Task Force members' increasingly complex understanding of the local HIV care system and demonstrated their improved capacity to visualize and critique multiple models of the HIV T&T service system and identify areas of potential leverage. Findings also showed members' enhanced communication and consensus in seeking deeper systems understanding and options for solutions. We discuss implications of using these visual SD models for subsequent simulation modeling of the T&T system and for other community applications to improve system effectiveness.

Factors That Influence Linkages to HIV Continuum of Care Services: Implications for Multi-Level Interventions

Worldwide, the human immunodeficiency virus (HIV) continuum of care involves health promotion providers (e.g., social workers and health educators) linking patients to medical personnel who provide HIV testing, primary care, and antiretroviral treatments. Regrettably, these life-saving linkages are not always made consistently and many patients are not retained in care. To design, test and implement effective interventions, we need to first identify key factors that may improve linkage-making. To help close this gap, we used in-depth interviews with 20 providers selected from a sample of 250 participants in a mixed-method longitudinal study conducted in New York City (2012–2017) in order to examine the implementation of HIV services for at-risk populations. Following a sociomedical framework, we identified provider-, interpersonal- and environmental-level factors that influence how providers engage patients in the care continuum by linking them to HIV testing, HIV care, and other support services. These factors occurred in four domains of reference: Providers’ Professional Knowledge Base; Providers’ Interprofessional Collaboration; Providers’ Work-Related Changes; and Best Practices in a Competitive Environment. Of particular importance, our findings show that a competitive environment and a fear of losing patients to other agencies may inhibit providers from engaging in linkage-making. Our results suggest relationships between factors within and across all four domains; we recommend interventions to modify factors in all domains for maximum effect toward improving care continuum linkage-making. Our findings may be applicable in different areas of the globe with high HIV prevalence.

Test-and-treat approach to HIV/AIDS: a primer for mathematical modeling

The public benefit of test-and-treat has induced a need to justify goodness for the public, and mathematical modeling studies have played a key role in designing and evaluating the test-and-treat strategy for controlling HIV/AIDS. Here we briefly and comprehensively review the essence of contemporary understanding of the test-and-treat policy through mathematical modeling approaches and identify key pitfalls that have been identified to date. While the decrease in HIV incidence is achieved with certain coverages of diagnosis, care and continued treatment, HIV prevalence is not necessarily decreased and sometimes the test-and-treat is accompanied by increased long-term cost of antiretroviral therapy (ART). To confront with the complexity of assessment on this policy, the elimination threshold or the effective reproduction number has been proposed for its use in determining the overall success to anticipate the eventual elimination. Since the publication of original model in 2009, key issues of test-and-treat modeling studies have been identified, including theoretical problems surrounding the sexual partnership network, heterogeneities in the transmission dynamics, and realistic issues of achieving and maintaining high treatment coverage in the most hard-to-reach populations. To explicitly design country-specific control policy, quantitative modeling approaches to each single setting with differing epidemiological context would require multi-disciplinary collaborations among clinicians, public health practitioners, laboratory technologists, epidemiologists and mathematical modelers.

Early detection of HIV infection and of asymptomatic sexually transmitted infections among men who have sex with men

OBJECTIVE

To provide data on incidence of early diagnosis of HIV infections and define prevalence and incidence of asymptomatic sexually transmitted infections (STI) in men who have sex with men (MSM).

METHODS

We assessed a prospective cohort study of HIV-uninfected MSM at high risk for HIV infection. Participants were selected through a risk-assessment questionnaire, and they were screened for HIV infection (quarterly) and for other STI (yearly): syphilis, and hepatitis A, B and C (serology); Chlamydia trachomatis and Neisseria gonorrhoeae in penis and rectum; and human papillomavirus in anus and mouth (PCR).

RESULTS

Between November 2009 and October 2012, a total of 258 HIV-uninfected MSM at high risk for HIV infection were included and followed up for a median of 2 years (interquartile range 1.4, 2.5). Nineteen acute HIV infections were diagnosed (incidence, 3.9 per 100 person-years). Prevalence of STI at baseline was follows: syphilis 8.4% (95% confidence interval (CI) 5.4-12.7); hepatitis C virus (HCV) 2.0% (95% CI 0.7-4.8); C. trachomatis in penis 3.2% (95% CI 1.5-6.5) and in rectum 6.5% (95% CI 3.9-10.5); N. gonorrhoeae in penis 2.0% (95% CI 0.8-5.0) and in rectum 6.1% (95% CI 3.6-10.1); human papillomavirus in anal canal 75.7% (95% CI 68.8-81.5) and in mouth 3.8% (95% CI 1.8-7.7).

CONCLUSIONS

The implementation of the Check-Ear Project in a MSM community centre allowed for the identification of early HIV infections and asymptomatic STI among MSM. The high incidence of HIV infections and the high prevalence of STI strongly support the recommendation of periodic screenings among sexually active MSM.

Rapid CD4 decline prior to antiretroviral therapy predicts subsequent failure to reconstitute despite HIV viral suppression

HIV-1 infection is characterized by loss of CD4T cells, leading to immunodeficiency. Initiation of antiretroviral therapy (ART) results in suppression of the viral load and increased CD4 counts. Both viral and host factors determine CD4 cell responses to ART with approximately 15-30% of individuals having suboptimal increase of CD4T cell count, most commonly due to lack of compliance to ART. A smaller fraction of patients will have immune reconstitution failure and suboptimal CD4 increase despite suppression of HIV replication, and these individuals are at risk for adverse health outcomes. We sought to characterize the factors associated with decreased immunological response among Manitoba's HIV patient population. This retrospective case-control study included HIV patients with immune reconstitution failure despite suppression of HIV replication by ART. The immune reconstitution failure was defined by CD4 cell count increase from baseline of less than 100 CD4 cells/mm³ or lack of increase to above 200 CD4 cells/mm³ within one year of viral load suppression. Age and nadir CD4 cell counts are known risk factors associated with immune reconstitution failure. We chose controls (Patients with immune reconstitution success) of similar age and CD4 nadir cell with cases (Patients with immune reconstitution failure). We explored the potential effects of gender, HLA type, presence of co-infection, ethnicity, ART type, and rate of pre-treatment CD4 decline among cases and controls. Of more than 550 patients followed by our HIV clinic, 42 individuals met our definition of immune reconstitution failure and they were assigned to the cases group. 31 patients, comprising a range of ages and CD4 nadirs similar to those of the cases, were assigned to the control group. Our primary analysis was a regression model, predicting post-ART change in CD4 over time. After controlling for age and nadir CD4 cell counts, the only potential predictor that appears consistently associated with the rate of post-ART rise in CD4 over time in our cohort, regardless of the other variables that we have controlled for, is the rate of decline in CD4 pre-ART initiation. Several factors have been variably correlated with immune reconstitution failure of CD4 T cell count. Age and low CD4 nadir are factors previously shown to correlate with immune reconstitution failure; and we have controlled for them in our study. Another possible predictor is the rate of decline in CD4 pre-ART, which can serve as an additional marker of reconstitution failure and necessitate prioritizing individuals to ART initiation or identification of a subset of individuals that may be targeted for future adjunct strategies to improve immune recovery.

Combined interventions to reduce HIV incidence in KwaZulu-Natal: a modelling study

BACKGROUND

Combined prevention interventions, including early antiretroviral therapy initiation, may substantially reduce HIV incidence in hyperendemic settings. Our aim was to assess the potential short-term impact of combined interventions on HIV spreading in the adult population of Mbongolwane and Eshowe (KwaZulu-Natal, South Africa) using sex- and age-specific scenarios, and age-targeted interventions.

METHODS

A mathematical model was used with data on adults (15-59 years) from the Mbongolwane and Eshowe HIV Impact in Population Survey to compare the effects of various interventions on the HIV incidence rate. These interventions included increase in antiretroviral therapy (ART) coverage with extended eligibility criteria, increase in voluntary medical male circumcision (VMMC), and implementation of pre-exposure prophylaxis (PrEP) among women.

RESULTS

With no additional interventions to the ones in place at the time of the survey (ART at CD4 < 350 and VMMC), incidence will decrease by 24% compared to the baseline rate. The implementation of "ART at CD4<500" or "ART for all" would reduce further the incidence rate by additional 8% and 15% respectively by 4 years and 20% and 34% by 10 years. Impacts would be higher with age-targeted scenarios than without.

CONCLUSIONS

In Mbongolwane and Eshowe, implementation of the new South African guidelines, recommending ART initiation regardless of CD4 count, would accelerate incidence reduction. In this setting, combining these guidelines, VMMC, and PrEP among young women could be an effective strategy in reducing the incidence to low levels.

Early antiretroviral therapy and potent second-line drugs could decrease HIV incidence of drug resistance

Early initiation of antiretroviral therapy (ART) reduces the risk of drug-sensitive HIV transmission but may increase the transmission of drug-resistant HIV. We used a mathematical model to estimate the long-term population-level benefits of ART and determine the scenarios under which earlier ART (treatment at 1 year post-infection, on average) could decrease simultaneously both total and drug-resistant HIV incidence (new infections). We constructed an infection-age-structured mathematical model that tracked the transmission rates over the course of infection and modelled the patients' life expectancy as a function of ART initiation timing. We fitted this model to the annual AIDS incidence and death data directly, and to resistance data and demographic data indirectly among men who have sex with men (MSM) in San Francisco. Using counterfactual scenarios, we assessed the impact on total and drug-resistant HIV incidence of ART initiation timing, frequency of acquired drug resistance, and second-line drug effectiveness (defined as the combination of resistance monitoring, biomedical drug efficacy and adherence). Earlier ART initiation could decrease the number of both total and drug-resistant HIV incidence when second-line drug effectiveness is sufficiently high (greater than 80%), but increase the proportion of new infections that are drug resistant. Thus, resistance may paradoxically appear to be increasing while actually decreasing.

Design of the HPTN 065 (TLC-Plus) study: A study to evaluate the feasibility of an enhanced test, link-to-care, plus treat approach for HIV prevention in the United States

Background/Aims

HIV continues to be a major public health threat in the United States, and mathematical modeling has demonstrated that the universal effective use of antiretroviral therapy among all HIV-positive individuals (i.e. the “test and treat” approach) has the potential to control HIV. However, to accomplish this, all the steps that define the HIV care continuum must be achieved at high levels, including HIV testing and diagnosis, linkage to and retention in clinical care, antiretroviral medication initiation, and adherence to achieve and maintain viral suppression. The HPTN 065 (Test, Link-to-Care Plus Treat [TLC-Plus]) study was designed to determine the feasibility of the “test and treat” approach in the United States.

Methods

HPTN 065 was conducted in two intervention communities, Bronx, NY, and Washington, DC, along with four non-intervention communities, Chicago, IL; Houston, TX; Miami, FL; and Philadelphia, PA. The study consisted of five components: (1) exploring the feasibility of expanded HIV testing via social mobilization and the universal offer of testing in hospital settings, (2) evaluating the effectiveness of financial incentives to increase linkage to care, (3) evaluating the effectiveness of financial incentives to increase viral suppression, (4) evaluating the effectiveness of a computer-delivered intervention to decrease risk behavior in HIV-positive patients in healthcare settings, and (5) administering provider and patient surveys to assess knowledge and attitudes regarding the use of antiretroviral therapy for prevention and the use of financial incentives to improve health outcomes. The study used observational cohorts, cluster and individual randomization, and made novel use of the existing national HIV surveillance data infrastructure. All components were developed with input from a community advisory board, and pragmatic methods were used to implement and assess the outcomes for each study component.

Results

A total of 76 sites in Washington, DC, and the Bronx, NY, participated in the study: 37 HIV test sites, including 16 hospitals, and 39 HIV care sites. Between September 2010 and December 2014, all study components were successfully implemented at these sites and resulted in valid outcomes. Our pragmatic approach to the study design, implementation, and the assessment of study outcomes allowed the study to be conducted within established programmatic structures and processes. In addition, it was successfully layered on the ongoing standard of care and existing data infrastructure without disrupting health services.

Conclusion

The HPTN 065 study demonstrated the feasibility of implementing and evaluating a multi-component “test and treat” trial that included a large number of community sites and involved pragmatic approaches to study implementation and evaluation.

Mortality in the First 3 Months on Antiretroviral Therapy Among HIV-Positive Adults in Low- and Middle-income Countries: A Meta-analysis

Previous meta-analyses reported mortality estimates of 12-month post-antiretroviral therapy (ART) initiation; however, 40%-60% of deaths occur in the first 3 months on ART, a more sensitive measure of averted deaths through early ART initiation. To determine whether early mortality is dropping as treatment thresholds have increased, we reviewed studies of 3 months on ART initiation in low- to middle-income countries. Studies of 3-month mortality from January 2003 to April 2016 were searched in 5 databases. Articles were included that reported 3-month mortality from a low- to middle-income country; nontrial setting and participants were ≥15. We assessed overall mortality and stratified by year using random effects models. Among 58 included studies, although not significant, pooled estimates show a decline in mortality when comparing studies whose enrollment of patients ended before 2010 (7.0%; 95% CI: 6.0 to 8.0) with the studies during or after 2010 (4.0%; 95% CI: 3.0 to 5.0). To continue to reduce early HIV-related mortality at the population level, intensified efforts to increase demand for ART through active testing and facilitated referral should be a priority. Continued financial investments by multinational partners and the implementation of creative interventions to mitigate multidimensional complex barriers of accessing care and treatment for HIV are needed.

It's a Process: Reactions to HIV Diagnosis and Engagement in HIV Care among High-Risk Heterosexuals

After HIV diagnosis, heterosexuals in high-poverty urban areas evidence delays in linkage to care and antiretroviral therapy initiation compared to other groups. Yet barriers to/facilitators of HIV care among these high-risk heterosexuals are understudied. Under the theory of triadic influence, putative barriers to HIV care engagement include individual/attitudinal-level (e.g., fear, medical distrust), social-level (e.g., stigma), and structural-level influences (e.g., poor access). Participants were African-American/Black and Hispanic adults found newly diagnosed with HIV (N = 25) as part of a community-based HIV testing study with heterosexuals in a high-poverty, high-HIV-incidence urban area. A sequential explanatory mixed-methods design was used. We described linkage to HIV care and clinical outcomes [CD4 counts, viral load (VL) levels] over 1 year, and then addressed qualitative research questions about the experience of receiving a new HIV diagnosis, its effects on timely engagement in HIV care, and other barriers and facilitators. Participants were assessed five times, receiving a structured interview battery, laboratory tests, data extraction from the medical record, a post-test counseling session, and in-person/phone contacts to foster linkage to care. Participants were randomly selected for qualitative interviews (N = 15/25) that were recorded and transcribed, then analyzed using systematic content analysis. Participants were 50 years old, on average (SD = 7.2 years), mostly male (80%), primarily African-American/Black (88%), and low socioeconomic status. At the first follow-up, rates of engagement in care were high (78%), but viral suppression was modest (39%). Rates improved by the final follow-up (96% engaged, 62% virally suppressed). Two-thirds (69%) were adequately retained in care over 1 year. Qualitative results revealed multi-faceted responses to receiving an HIV diagnosis. Problems accepting and internalizing one’s HIV status were common. Reaching acceptance of one’s HIV-infected status was frequently a protracted and circuitous process, but acceptance is vital for engagement in HIV care. Fear of stigma and loss of important relationships were potent barriers to acceptance. Thus, partially as a result of difficulties accepting HIV status, delays in achieving an undetectable VL are common in this population, with serious potential negative consequences for individual and public health. Interventions to foster acceptance of HIV status are needed.

A universal testing and treatment intervention to improve HIV control: One-year results from intervention communities in Zambia in the HPTN 071 (PopART) cluster-randomised trial

BACKGROUND

The Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets require that, by 2020, 90% of those living with HIV know their status, 90% of known HIV-positive individuals receive sustained antiretroviral therapy (ART), and 90% of individuals on ART have durable viral suppression. The HPTN 071 (PopART) trial is measuring the impact of a universal testing and treatment intervention on population-level HIV incidence in 21 urban communities in Zambia and South Africa. We report observational data from four communities in Zambia to assess progress towards the UNAIDS targets after 1 y of the PopART intervention.

METHODS AND FINDINGS

The PopART intervention comprises annual rounds of home-based HIV testing delivered by community HIV-care providers (CHiPs) who also support linkage to care, ART retention, and other services. Data from four communities in Zambia receiving the full intervention (including immediate ART for all individuals with HIV) were used to determine proportions of participants who knew their HIV status after the CHiP visit; proportions linking to care and initiating ART following referral; and overall proportions of HIV-infected individuals who knew their status (first 90 target) and the proportion of these on ART (second 90 target), pre- and post-intervention. We are not able to assess progress towards the third 90 target at this stage of the study. Overall, 121,130 adults (59,283 men and 61,847 women) were enumerated in 46,714 households during the first annual round (December 2013 to June 2015). Of the 45,399 (77%) men and 55,703 (90%) women consenting to the intervention, 80% of men and 85% of women knew their HIV status after the CHiP visit. Of 6,197 HIV-positive adults referred by CHiPs, 42% (95% CI: 40%-43%) initiated ART within 6 mo and 53% (95% CI: 52%-55%) within 12 mo. In the entire population, the estimated proportion of HIV-positive adults who knew their status increased from 52% to 78% for men and from 56% to 87% for women. The estimated proportion of known HIV-positive individuals on ART increased overall from 54% after the CHiP visit to 74% by the end of the round for men and from 53% to 73% for women. The estimated overall proportion of HIV-positive adults on ART, irrespective of whether they knew their status, increased from 44% to 61%, compared with the 81% target (the product of the first two 90 targets). Coverage was lower among young men and women than in older age groups. The main limitation of the study was the need for assumptions concerning knowledge of HIV status and ART coverage among adults not consenting to the intervention or HIV testing, although our conclusions were robust in sensitivity analyses.

CONCLUSIONS

In this analysis, acceptance of HIV testing among those consenting to the intervention was high, although linkage to care and ART initiation took longer than expected. Knowledge of HIV-positive status increased steeply after 1 y, almost attaining the first 90 target in women and approaching it in men. The second 90 target was more challenging, with approximately three-quarters of known HIV-positive individuals on ART by the end of the annual round. Achieving higher test uptake in men and more rapid linkage to care will be key objectives during the second annual round of the intervention.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01900977.

Qualitative insights into implementation, processes, and outcomes of a randomized trial on peer support and HIV care engagement in Rakai, Uganda

BACKGROUND

People living with human immunodeficiency virus (HIV) who have not yet initiated antiretroviral therapy (ART) can benefit from being engaged in care and utilizing preventive interventions. Community-based peer support may be an effective approach to promote these important HIV services.

METHODS

After conducting a randomized trial of the impact of peer support on pre-ART outcomes, we conducted a qualitative evaluation to better understand trial implementation, processes, and results. Overall, 75 participants, including trial participants (clients), peer supporters, and clinic staff, participated in 41 in-depth interviews and 6 focus group discussions. A situated Information Motivation, and Behavioral skills model of behavior change was used to develop semi-structured interview and focus group guides. Transcripts were coded and thematically synthesized.

RESULTS

We found that participant narratives were generally consistent with the theoretical model, indicating that peer support improved information, motivation, and behavioral skills, leading to increased engagement in pre-ART care. Clients described how peer supporters reinforced health messages and helped them better understand complicated health information. Peer supporters also helped clients navigate the health system, develop support networks, and identify strategies for remembering medication and clinic appointments. Some peer supporters adopted roles beyond visiting patients, serving as a bridge between the client and his or her family, community, and health system. Qualitative results demonstrated plausible processes by which peer support improved client engagement in care, cotrimoxazole use, and safe water vessel use. Challenges identified included insufficient messaging surrounding ART initiation, lack of care continuity after ART initiation, rare breaches in confidentiality, and structural challenges.

CONCLUSIONS

The evaluation found largely positive perceptions of the peer intervention across stakeholders and provided valuable information to inform uptake and scalability of the intervention. Study findings also suggest several areas for improvement for future implementation of pre-ART peer support programs.

TRIAL REGISTRATION

NCT01366690 . Registered June 2, 2011.

Beyond Condoms: Risk Reduction Strategies Among Gay, Bisexual, and Other Men Who Have Sex With Men Receiving Rapid HIV Testing in Montreal, Canada

Gay, bisexual, and other men who have sex with men (MSM) have adapted their sexual practices over the course of the HIV/AIDS epidemic based on available data and knowledge about HIV. This study sought to identify and compare patterns in condom use among gay, bisexual, and other MSM who were tested for HIV at a community-based testing site in Montreal, Canada. Results showed that while study participants use condoms to a certain extent with HIV-positive partners and partners of unknown HIV status, they also make use of various other strategies such as adjusting to a partner's presumed or known HIV status and viral load, avoiding certain types of partners, taking PEP, and getting tested for HIV. These findings suggest that MSM who use condoms less systematically are not necessarily taking fewer precautions but may instead be combining or replacing condom use with other approaches to risk reduction.

Treatment And Prevention for female Sex workers in South Africa: protocol for the TAPS Demonstration Project

INTRODUCTION

Updated guidelines from the WHO recommend antiretroviral treatment for adults with HIV at any CD4 count and daily oral pre-exposure prophylaxis (PrEP) for people at substantial risk of HIV infection. However, implementation challenges may hinder the ability of programmes to translate these recommendations into successful practice. This demonstration project is the first to integrate PrEP and immediate treatment (ITx) for female sex workers (FSWs) in South Africa to answer operational research questions.

METHODS AND ANALYSIS

This is a prospective cohort study where the main outcome is retention at 12 months. The study population is recruited into two arms across two urban sites: (1) PrEP for HIV-negative FSWs (n=400) and (2) ITx for HIV-positive FSWs with CD4 greater than national guidelines (n=300). We investigate process and other health indicators, uptake and use of PrEP and ITx through qualitative research, and evaluate cost-effectiveness analysis combined with estimates of impact through epidemiological modelling.

ETHICS AND DISSEMINATION

The Treatment And Prevention for female Sex workers in South Africa (TAPS) Project was designed as an implementation study before emtricitabine/tenofovir disoproxil fumarate was licenced as an indication for PrEP in South Africa. Therefore, clinical trial requirements for ethical and South African Medicines Control Council approvals were followed. Results will be disseminated to participants, local health officials and other stakeholders, as well as in peer-reviewed journals and at conferences.

Beyond Risk Compensation: Clusters of Antiretroviral Treatment (ART) Users in Sexual Networks Can Modify the Impact of ART on HIV Incidence

Introduction

Concerns about risk compensation—increased risk behaviours in response to a perception of reduced HIV transmission risk—after the initiation of ART have largely been dispelled in empirical studies, but other changes in sexual networking patterns may still modify the effects of ART on HIV incidence.

Methods

We developed an exploratory mathematical model of HIV transmission that incorporates the possibility of ART clusters, i.e. subsets of the sexual network in which the density of ART patients is much higher than in the rest of the network. Such clusters may emerge as a result of ART homophily—a tendency for ART patients to preferentially form and maintain relationships with other ART patients. We assessed whether ART clusters may affect the impact of ART on HIV incidence, and how the influence of this effect-modifying variable depends on contextual variables such as HIV prevalence, HIV serosorting, coverage of HIV testing and ART, and adherence to ART.

Results

ART homophily can modify the impact of ART on HIV incidence in both directions. In concentrated epidemics and generalized epidemics with moderate HIV prevalence (≈ 10%), ART clusters can enhance the impact of ART on HIV incidence, especially when adherence to ART is poor. In hyperendemic settings (≈ 35% HIV prevalence), ART clusters can reduce the impact of ART on HIV incidence when adherence to ART is high but few people living with HIV (PLWH) have been diagnosed. In all contexts, the effects of ART clusters on HIV epidemic dynamics are distinct from those of HIV serosorting.

Conclusions

Depending on the programmatic and epidemiological context, ART clusters may enhance or reduce the impact of ART on HIV incidence, in contrast to serosorting, which always leads to a lower impact of ART on HIV incidence. ART homophily and the emergence of ART clusters should be measured empirically and incorporated into more refined models used to plan and evaluate ART programmes.

Factors associated with changes in uptake of HIV testing among young women (aged 15-24) in Tanzania from 2003 to 2012

Background

This study explored the factors associated with changes in HIV testing uptake among young women in Tanzania, based on an analysis of data from the 2003–2004 Tanzania HIV/AIDS Indicator Survey, and the 2007–2008 and 2011–2012 Tanzania HIV/AIDS and Malaria Indicator Surveys.

Methods

The study population consisted of young women aged 15–24 years at the time of the survey. Multivariate decomposition analysis was used to assess factors associated with changes in HIV testing uptake between the 2003–2004 and 2007–2008 surveys, and between the 2007–2008 and 2011–2012 surveys.

Results

HIV testing uptake among the study population was 7 % in 2003–2004, 31 % in 2007–2008 and 40 % in 2011–2012. The time period of the survey had a substantial effect on the uptake of HIV testing independent of other covariates. The characteristics that were significantly associated with a higher chance of HIV testing uptake across the surveys were age (20–24), education level (primary and secondary), ever being married, having at least one lifetime sexual partner, having a sexually transmitted infection or associated symptoms, and receiving antenatal care.

Conclusions

Changes in the study participants’ characteristics in the 2003–2004 survey compared with the 2007–2008 survey were associated with a decrease in HIV testing uptake. Comparing the 2007–2008 survey with the 2011–2012 survey shows that the changes in the participants’ characteristics contributed to 22 % of the changes in HIV testing uptake, while 78 % of the changes were attributed to coefficients.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0180-3) contains supplementary material, which is available to authorized users.