High Transmissibility During Early HIV Infection Among Men Who Have Sex With Men-San Francisco, California

Evaluation of SAMBA II: A Qualitative and Semiquantitative HIV Point-of-Care Nucleic Acid Test

BACKGROUND

Point-of-care (POC) nucleic acid tests (NATs) have potential to diagnose acute HIV infection and monitor persons taking pre-exposure prophylaxis or antiretroviral therapy (ART). POC NATs have not yet been evaluated in the US.

METHODS

From June 2018-March 2019, we conducted a cross-sectional evaluation of the Simple Amplification-Based Assay version II (SAMBA II) POC NAT. People with HIV (PWH) and persons testing for HIV were tested with the SAMBA II qualitative (Qual) whole blood (WB) test. From April-September 2019, the Qual test was used on persons who were ART-naive, and SAMBA II Semi-quantitative (Semi-Q) WB was used with ART-experienced PWH. Both were performed on unprocessed venipuncture (VP) and, when indicated by protocol, fingerstick (FS) WB and plasma. SAMBA results were compared with Abbott RealTime HIV-1 polymerase chain reaction results on plasma. We calculated sensitivity, specificity, and concordance between tests.

RESULTS

SAMBA was used in 330 visits among 280 participants: 202 (61.2%) visits from PWH, and 128 (38.8%) from HIV-negative persons. Qual test sensitivity with ART-naive participants was 91.4% [32/35, 95% confidence interval (CI): 77.6% to 97.0%] using VP WB and 100% (27/27, 95% CI: 87.5% to 100%) using FS WB. Specificity was 100% using both specimen types. Concordance between the gold standard and Semi-Q at 1000 copies/mL among PWH on ART was 97.7% (86/88, 95% CI: 92.1% to 99.4%) and 100% (30/30, 95% CI: 88.7% to 100%) using VP and FS WB, respectively.

CONCLUSIONS

The SAMBA II POC NATs showed high sensitivity, specificity, and concordance with the gold standard assay, indicating its potential use in diagnostics and monitoring. Future work will evaluate POC NAT implementation in the US.

Go Where the Virus Is: An HIV Micro-epidemic Control Approach to Stop HIV Transmission

Essentially all HIV transmission is from people living with HIV who are not virally suppressed. An HIV micro-epidemic control approach that differentiates treatment support and prevention services for people living with HIV and their network members according to viral burden could optimize the impact of epidemic control efforts.

Number of HIV-1 founder variants is determined by the recency of the source partner infection

During sexual transmission, the high genetic diversity of HIV-1 within an individual is frequently reduced to one founder variant that initiates infection. Understanding the drivers of this bottleneck is crucial to developing effective infection control strategies. Little is known about the importance of the source partner during this bottleneck. To test the hypothesis that the source partner affects the number of HIV founder variants, we developed a phylodynamic model calibrated using genetic and epidemiological data on all existing transmission pairs for whom the direction of transmission and the infection stage of the source partner are known. Our results suggest that acquiring infection from someone in the acute (early) stage of infection increases the risk of multiple-founder variant transmission compared with acquiring infection from someone in the chronic (later) stage of infection. This study provides the first direct test of source partner characteristics to explain the low frequency of multiple-founder strain infections.

Challenges of HIV diagnosis and management in the context of pre-exposure prophylaxis (PrEP), post-exposure prophylaxis (PEP), test and start and acute HIV infection: a scoping review

INTRODUCTION

Knowledge of HIV status relies on accurate HIV testing, and is the first step towards access to HIV treatment and prevention programmes. Globally, HIV-status unawareness represents a significant challenge for achieving zero new HIV infections and deaths. In order to enhance knowledge of HIV status, the World Health Organisation (WHO) recommends a testing strategy that includes the use of HIV-specific antibody point-of-care tests (POCT). These POCTs do not detect acute HIV infection, the stage of disease when viral load is highest but HIV antibodies are undetectable. Complicating things further, in the presence of antiretroviral therapy (ART) for pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP), other currently available testing technologies, such as viral load detection for diagnosis of acute HIV infection, may yield false-negative results. In this scoping review, we evaluate the evidence and discuss alternative HIV testing algorithms that may mitigate diagnostic dilemmas in the setting of increased utilization of ART for immediate treatment and prevention of HIV infection.

DISCUSSION

Missed acute HIV infection prevents people living with HIV (PLHIV) from accessing early treatment, increases likelihood of onward transmission, and allows for inappropriate initiation or continuation of PrEP, which may result in HIV drug resistance. While immediate ART is recommended for all PLHIV, studies have shown that starting ART in the setting of acute HIV infection may result in a delayed or complete absence of development of HIV-specific antibodies, posing a diagnostic challenge that is particularly pertinent to resource-limited, high HIV burden settings where HIV-antibody POCTs are standard of care. Similarly, ART used as PrEP or PEP may supress HIV RNA viral load, complicating current HIV testing algorithms in resource-wealthy settings where viral detection is included. As rollout of PrEP continues, HIV testing algorithms may need to be modified.

CONCLUSIONS

With increasing use of PrEP and ART in acute infection we anticipate diagnostic challenges using currently available HIV testing strategies. Research and surveillance are needed to determine the most appropriate assays and optimal testing algorithms that are accurate, affordable and sustainable.

Molecular Epidemiology of HIV-1 Subtype B Reveals Heterogeneous Transmission Risk: Implications for Intervention and Control

Background

The impact of HIV pre-exposure prophylaxis (PrEP) depends on infections averted by protecting vulnerable individuals as well as infections averted by preventing transmission by those who would have been infected if not receiving PrEP. Analysis of HIV phylogenies reveals risk factors for transmission, which we examine as potential criteria for allocating PrEP.

Methods

We analyzed 6912 HIV-1 partial pol sequences from men who have sex with men (MSM) in the United Kingdom combined with global reference sequences and patient-level metadata. Population genetic models were developed that adjust for stage of infection, global migration of HIV lineages, and changing incidence of infection through time. Models were extended to simulate the effects of providing susceptible MSM with PrEP.

Results

We found that young age <25 years confers higher risk of HIV transmission (relative risk = 2.52 [95% confidence interval, 2.32–2.73]) and that young MSM are more likely to transmit to one another than expected by chance. Simulated interventions indicate that 4-fold more infections can be averted over 5 years by focusing PrEP on young MSM.

Conclusions

Concentrating PrEP doses on young individuals can avert more infections than random allocation.

Efficacy and cost-effectiveness of early antiretroviral therapy and partners' pre-exposure prophylaxis among men who have sex with men in Shenyang, China: a prospective cohort and costing study

BACKGROUND

Biomedical interventions such as antiretroviral therapy (ART) and pre-exposure prophylaxis (PrEP) are highly effective for prevention of human immunodeficiency virus (HIV) infection. However, China has not released national PrEP guidelines, and HIV incidence among men who have sex with men (MSM) is unchanged despite substantial scale-up of ART. We evaluated reductions in HIV transmission that may be achieved through early initiation of ART plus partners' PrEP.

METHODS

Six intervention scenarios were evaluated in terms of their impact on HIV transmission and their cost-effectiveness for 36 months post-infection. Three scenarios were based on observed data: non-ART, standard-ART, and early-ART. Another three scenarios were based on observed and hypothetical data: non-ART plus partners' PrEP, standard-ART plus partners' PrEP, and early-ART plus partners' PrEP. The number of onward transmissions was calculated according to viral load and self-reported sexual behaviors, and calibrated by the prevalence and incidence of HIV among Chinese MSM. Cost-effectiveness outcomes were quality-adjusted life-years (QALYs) and cost-utility ratio (CUR).

RESULTS

The estimated number of onward transmissions by every 100 HIV-positive cases 36 months post-infection was 41.83 (95% credible interval: 30.75-57.69) in the non-ART scenario, 7.95 (5.85-10.95) in the early-ART scenario, and 0.79 (0.58-1.09) in the early-ART plus partners' PrEP scenario. Compared with non-ART, the early-ART and early-ART plus partners' PrEP scenarios were associated with an 81.0 and 98.1% reduction in HIV transmission, and had a CUR of $12,864/QALY and $16,817/QALY, respectively.

CONCLUSIONS

Integrated delivery of early ART and sexual partners' PrEP could nearly eliminate HIV transmission and reduce costs during the first 36 months of HIV infection. Our results suggest a feasible and cost-effective strategy for reversing the HIV epidemic among MSM in China.

Projected effectiveness of HIV detection during early infection and rapid ART initiation among MSM and transgender women in Peru: A modeling study

Background

The Sabes study, a treatment as prevention intervention in Peru, tested the hypothesis that initiating antiretroviral therapy (ART) early in HIV infection when viral load is high, would markedly reduce onward HIV transmission among high-risk men who have sex with men (MSM) and transgender women (TW). We investigated the potential population-level benefits of detection of HIV early after acquisition and rapid initiation of ART.

Methods

We designed a transmission dynamic model to simulate the HIV epidemic among MSM and TW in Peru, calibrated to data on HIV prevalence and ART coverage from 2004 to 2011. We assessed the impact of an intervention starting in 2018 in which up to 50% of the new infections were diagnosed within three months of acquisition and initiated on ART within 1 month of diagnosis. We estimated the impact of the intervention over 20 years using the cumulative prevented fraction of new HIV infections compared to scenarios without intervention.

Findings

Our model suggests that only 19% of the infected MSM and TW are virally suppressed in 2018 and 35%-40% of the new HIV infections are transmitted from contacts with acutely-infected partners. An intervention reaching 10% of all acutely infected MSM and TW is projected to prevent 13.3% [Uncertainty interval: 11.9%-14.3%] of the new infections over 20 years and reduce HIV incidence in 2038 by 24%. Reaching 50% of all acutely infected MSM and TW will increase the prevalence of viral suppression in 2038 to 59% and prevent 41% of expected infections over 20 years. Reaching 50% of the high-risk MSM and TW in acute phase would reduce HIV incidence in 2038 by 60% and prevent 36% of new infections between 2018 and 2038.

Conclusions

Early detection of HIV infections and rapid initiation of ART among MSM is desirable as it would increase the effectiveness of the HIV prevention program in Peru. Targeting high-risk MSM and TW will be highly efficient.

Link between the numbers of particles and variants founding new HIV-1 infections depends on the timing of transmission

Understanding which HIV-1 variants are most likely to be transmitted is important for vaccine design and predicting virus evolution. Since most infections are founded by single variants, it has been suggested that selection at transmission has a key role in governing which variants are transmitted. We show that the composition of the viral population within the donor at the time of transmission is also important. To support this argument, we developed a probabilistic model describing HIV-1 transmission in an untreated population, and parameterised the model using both within-host next generation sequencing data and population-level epidemiological data on heterosexual transmission. The most basic HIV-1 transmission models cannot explain simultaneously the low probability of transmission and the non-negligible proportion of infections founded by multiple variants. In our model, transmission can only occur when environmental conditions are appropriate (e.g. abrasions are present in the genital tract of the potential recipient), allowing these observations to be reconciled. As well as reproducing features of transmission in real populations, our model demonstrates that, contrary to expectation, there is not a simple link between the number of viral variants and the number of viral particles founding each new infection. These quantities depend on the timing of transmission, and infections can be founded with small numbers of variants yet large numbers of particles. Including selection, or a bias towards early transmission (e.g. due to treatment), acts to enhance this conclusion. In addition, we find that infections initiated by multiple variants are most likely to have derived from donors with intermediate set-point viral loads, and not from individuals with high set-point viral loads as might be expected. We therefore emphasise the importance of considering viral diversity in donors, and the timings of transmissions, when trying to discern the complex factors governing single or multiple variant transmission.

The early bird gets the worm: benefits and future directions with early antiretroviral therapy initiation in primary HIV infection

Primary HIV infection is defined as the first few weeks after infection where plasma viremia is rapidly increasing. Early diagnosis of primary HIV infection enhances the tendency of behavioral changes in newly infected individuals to prevent secondary HIV transmission. Early antiretroviral therapy (ART) benefits individuals by reducing plasma viral load, gut damage, microbial translocation and subsequent systemic immune activation. Early ART leads to the establishment of low HIV reservoir size that may contribute to HIV eradication research. However, substantial diagnostic and logistical barriers remain as a burden to rapid diagnosis and early treatment initiation. In this review, we critically evaluate the effects of early ART and summarize hurdles that must be addressed to implement rapid treatment initiation for newly infected individuals.

Sustained Reduction in Sexual Behavior that May Pose a Risk of HIV Transmission Following Diagnosis During Early HIV Infection Among Gay Men in Vancouver, British Columbia

Increased viral load during early HIV infection (EHI) disproportionately contributes to HIV transmission among gay men. We examined changes in sexual behavior that may pose a risk of HIV transmission (condomless anal sex (AS) with a serodiscordant or unknown status partner, CAS-SDU) in a cohort of 25 gay men newly diagnosed during EHI who provided information on 241 sexual partners at six time points following diagnosis. Twenty-two (88%) participants reported ≥1 AS partner (median time to first AS 80 days) and 12 (55%) reported ≥1 partnership involving CAS-SDU (median 116 days). In hierarchical generalized linear mixed effects models, AS was significantly less likely in all time periods following diagnosis and more likely with serodiscordant partners. The likelihood of CAS-SDU decreased three months after diagnosis and was higher in recently versus acutely infected participants. Most men in our study abstained from sex immediately after diagnosis with sustained longer-term reduction in CAS-SDU, confirming the importance of timely diagnosis during EHI.

Acute HIV infection detection and immediate treatment estimated to reduce transmission by 89% among men who have sex with men in Bangkok

Introduction: Antiretroviral treatment (ART) reduces HIV transmission. Despite increased ART coverage, incidence remains high among men who have sex with men (MSM) in many places. Acute HIV infection (AHI) is characterized by high viral replication and increased infectiousness. We estimated the feasible reduction in transmission by targeting MSM with AHI for early ART.

Methods: We recruited a cohort of 88 MSM with AHI in Bangkok, Thailand, who initiated ART immediately. A risk calculator based on viral load and reported behaviour, calibrated to Thai epidemiological data, was applied to estimate the number of onwards transmissions. This was compared with the expected number without early interventions.

Results: Forty of the MSM were in 4th-generation AHI stages 1 and 2 (4thG stage 1, HIV nucleic acid testing (NAT)+/4thG immunoassay (IA)-/3rdG IA–; 4thG stage 2, NAT+/4thG IA+/3rdG IA–) while 48 tested positive on third-generation IA but had negative or indeterminate western blot (4thG stage 3). Mean plasma HIV RNA was 5.62 log¹⁰ copies/ml. Any condomless sex in the four months preceding the study was reported by 83.7%, but decreased to 21.2% by 24 weeks on ART. After ART, 48/88 (54.6%) attained HIV RNA <50 copies/ml by week 8, increasing to 78/87 (89.7%), and 64/66 (97%) at weeks 24 and 48, respectively. The estimated number of onwards transmissions in the first year of infection would have been 27.3 (95% credible interval: 21.7–35.3) with no intervention, 8.3 (6.4–11.2) with post-diagnosis behaviour change only, 5.9 (4.4–7.9) with viral load reduction only and 3.1 (2.4–4.3) with both. The latter was associated with an 88.7% (83.8–91.1%) reduction in transmission.

Conclusions: Disproportionate HIV transmission occurs during AHI. Diagnosis of AHI with early ART initiation can substantially reduce onwards transmission.

Clinical and public health implications of acute and early HIV detection and treatment: a scoping review

INTRODUCTION

The unchanged global HIV incidence may be related to ignoring acute HIV infection (AHI). This scoping review examines diagnostic, clinical, and public health implications of identifying and treating persons with AHI.

METHODS

We searched PubMed, in addition to hand-review of key journals identifying research pertaining to AHI detection and treatment. We focused on the relative contribution of AHI to transmission and the diagnostic, clinical, and public health implications. We prioritized research from low- and middle-income countries (LMICs) published in the last fifteen years.

RESULTS AND DISCUSSION

Extensive AHI research and limited routine AHI detection and treatment have begun in LMIC. Diagnostic challenges include ease-of-use, suitability for application and distribution in LMIC, and throughput for high-volume testing. Risk score algorithms have been used in LMIC to screen for AHI among individuals with behavioural and clinical characteristics more often associated with AHI. However, algorithms have not been implemented outside research settings. From a clinical perspective, there are substantial immunological and virological benefits to identifying and treating persons with AHI - evading the irreversible damage to host immune systems and seeding of viral reservoirs that occurs during untreated acute infection. The therapeutic benefits require rapid initiation of antiretrovirals, a logistical challenge in the absence of point-of-care testing. From a public health perspective, AHI diagnosis and treatment is critical to: decrease transmission via viral load reduction and behavioural interventions; improve pre-exposure prophylaxis outcomes by avoiding treatment initiation for HIV-seronegative persons with AHI; and, enhance partner services via notification for persons recently exposed or likely transmitting.

CONCLUSIONS

There are undeniable clinical and public health benefits to AHI detection and treatment, but also substantial diagnostic and logistical barriers to implementation and scale-up. Effective early ART initiation may be critical for HIV eradication efforts, but widespread use in LMIC requires simple and accurate diagnostic tools. Implementation research is critical to facilitate sustainable integration of AHI detection and treatment into existing health systems and will be essential for prospective evaluation of testing algorithms, point-of-care diagnostics, and efficacious and effective first-line regimens.

The Effect of Same-Day Observed Initiation of Antiretroviral Therapy on HIV Viral Load and Treatment Outcomes in a US Public Health Setting

BACKGROUND

Antiretroviral therapy (ART) is typically begun weeks after HIV diagnosis. We assessed the acceptability, feasibility, safety, and efficacy of initiating ART on the same day as diagnosis.

METHODS

We studied a clinic-based cohort consisting of consecutive patients who were referred with new HIV diagnosis between June 2013 and December 2014. A subset of patients with acute or recent infection (<6 months) or CD4 <200 were managed according to a "RAPID" care initiation protocol. An intensive, same-day appointment included social needs assessment; medical provider evaluation; and a first ART dose offered after laboratories were drawn. Patient acceptance of ART, drug toxicities, drug resistance, and time to viral suppression outcomes were compared between RAPID participants and contemporaneous patients (who were not offered the program), and with an historical cohort.

RESULTS

Among 86 patients, 39 were eligible and managed on the RAPID protocol. Thirty-seven (94.9%) of 39 in RAPID began ART within 24 hours. Minor toxicity with the initial regimen occurred in 2 (5.1%) of intervention patients versus none in the nonintervention group. Loss to follow-up was similar in intervention (10.3%) and nonintervention patients (14.9%) during the study. Time to virologic suppression (<200 copies HIV RNA/mL) was significantly faster (median 1.8 months) among intervention-managed patients when compared with patients treated in the same clinic under prior recommendations for universal ART (4.3 months; P = 0.0001).

CONCLUSIONS

Treatment for HIV infection can be started on the day of diagnosis without impacting the safety or acceptability of ART. Same-day ART may shorten the time to virologic suppression.

Performance of the Bio-Rad Geenius HIV1/2 Supplemental Assay in Detecting "Recent" HIV Infection and Calculating Population Incidence

Objective:

HIV seroconversion biomarkers are being used in cross-sectional studies for HIV incidence estimation. Bio-Rad Geenius HIV-1/2 Supplemental Assay is an immunochromatographic single-use assay that measures antibodies (Ab) against multiple HIV-1/2 antigens. The objective of this study was to determine whether the Geenius assay could additionally be used for recency estimation.

Design:

This assay was developed for HIV-1/2 confirmation; however, quantitative data acquired give information on increasing concentration and diversity of antibody responses over time during seroconversion. A quantitative threshold of recent HIV infection was proposed to determine “recent” or “nonrecent” HIV infection; performance using this cutoff was evaluated.

Methods:

We tested 2500 highly characterized specimens from research subjects in the United States, Brazil, and Africa with well-defined durations of HIV infection. Regression and frequency estimation were used to estimate assay properties relevant to HIV incidence measurement: mean duration of recent infection (MDRI), false-recent rate, and assay reproducibility and robustness.

Results:

Using the manufacturer's proposed cutoff index of 1.5 to identify “recent” infection, the assay has an estimated false-recent rate of 4.1% (95% CI: 2.2 to 7.0) and MDRI of 179 days (155 to 201) in specimens from treatment-naive subjects, presenting performance challenges similar to other incidence assays. Lower index cutoffs associated with lower MDRI gave a lower rate of false-recent results.

Conclusions:

These data suggest that with additional interpretive analysis of the band intensities using an algorithm and cutoff, the Geenius HIV-1/2 Supplemental Assay can be used to identify recent HIV infection in addition to confirming the presence of HIV-1 and HIV-2 antibodies.

The HIV Care Cascade and sub-analysis of those linked to but not retained in care: the experience from a tertiary HIV referral service in Dublin Ireland

BACKGROUND

The HIV Care Cascade model can be used to measure how clinical services align with United Nations' (UN) HIV treatment targets. Previous models have highlighted sequential losses at each step of the Cascade with a significant proportion being not retained in care (NRIC).

OBJECTIVE

We aimed to assess the feasibility of meeting the UN targets and assess factors associated with, and calculate the true proportion of those, NRIC.

METHODS

All people living with HIV who were linked to our service, one of three specialist HIV care providers in Dublin Ireland, from its establishment in 1993 to 1 December 2014, were included in the cohort and were categorized as linked to care, retained in care (RIC), on antiretroviral therapy (on ART), virally suppressed (HIV RNA <40copies/ml), and NRIC. An analysis of those NRIC was performed to categorize their current status through direct/indirect contact.

RESULTS

Of 1000 patients linked to care, 78.7% (n = 787) were RIC, of whom 91.5% (n = 720) were on ART, with 89.9% (n = 644) virally suppressed. Those RIC were more likely older (p = 0.006) and non-IVDU (p < 0.001). Of 213 (21.3%) NRIC, 56 (26.3%) emigrated, 27 (12.7%) transferred care, 15 (7.0%) stopped attending but were contactable, 38 (17.8%) died, and 77 (36.1%) were lost to follow-up. After revision, 10.5% of the cohort was confirmed as NRIC, with 6 of 15 defined as "stopped attending" re-linked to care following direct contact.

CONCLUSIONS

Our HIV Care Cascade model demonstrates that the true numbers of patients NRIC may be significantly lower than previously estimated and once RIC, treatment goals approaching the United Nations Programme on HIV and AIDS targets are possible with 91.5% on treatment and almost 90% of those on treatment virally suppressed. That 40% reengaged following direct contact suggests benefit through regular monitoring and direct contact based on the HIV Care Cascade model.

Prospective Study of Acute HIV-1 Infection in Adults in East Africa and Thailand

BACKGROUND

Acute human immunodeficiency virus type 1 (HIV-1) infection is a major contributor to transmission of HIV-1. An understanding of acute HIV-1 infection may be important in the development of treatment strategies to eradicate HIV-1 or achieve a functional cure.

METHODS

We performed twice-weekly qualitative plasma HIV-1 RNA nucleic acid testing in 2276 volunteers who were at high risk for HIV-1 infection. For participants in whom acute HIV-1 infection was detected, clinical observations, quantitative measurements of plasma HIV-1 RNA levels (to assess viremia) and HIV antibodies, and results of immunophenotyping of lymphocytes were obtained twice weekly.

RESULTS

Fifty of 112 volunteers with acute HIV-1 infection had two or more blood samples collected before HIV-1 antibodies were detected. The median peak viremia (6.7 log10 copies per milliliter) occurred 13 days after the first sample showed reactivity on nucleic acid testing. Reactivity on an enzyme immunoassay occurred at a median of 14 days. The nadir of viremia (4.3 log10 copies per milliliter) occurred at a median of 31 days and was nearly equivalent to the viral-load set point, the steady-state viremia that persists durably after resolution of acute viremia (median plasma HIV-1 RNA level, 4.4 log10 copies per milliliter). The peak viremia and downslope were correlated with the viral-load set point. Clinical manifestations of acute HIV-1 infection were most common just before and at the time of peak viremia. A median of one symptom of acute HIV-1 infection was recorded at a median of two study visits, and a median of one sign of acute HIV-1 infection was recorded at a median of three visits.

CONCLUSIONS

The viral-load set point occurred at a median of 31 days after the first detection of plasma viremia and correlated with peak viremia. Few symptoms and signs were observed during acute HIV-1 infection, and they were most common before peak viremia. (Funded by the Department of Defense and the National Institute of Allergy and Infectious Diseases.).

Role of HLA Adaptation in HIV Evolution

Killing of HIV-infected cells by CD8⁺ T-cells imposes strong selection pressure on the virus toward escape. The HLA class I molecules that are successful in mediating some degree of control over the virus are those that tend to present epitopes in conserved regions of the proteome, such as in p24 Gag, in which escape also comes at a significant cost to viral replicative capacity (VRC). In some instances, compensatory mutations can fully correct for the fitness cost of such an escape variant; in others, correction is only partial. The consequences of these events within the HIV-infected host, and at the population level following transmission of escape variants, are discussed. The accumulation of escape mutants in populations over the course of the epidemic already shows instances of protective HLA molecules losing their impact, and in certain cases, a modest decline in HIV virulence in association with population-level increase in mutants that reduce VRC.

Performance of Determine Combo and other point-of-care HIV tests among Seattle MSM

BACKGROUND AND OBJECTIVE

The rapid test study was a real-time comparison of point-of-care (POC) HIV tests to determine their abilities to detect early HIV infection.

STUDY DESIGN

Men and transgender persons reporting sex with men in the prior year were recruited at the Public Health-Seattle & King County STD Clinic, Gay City Health Project, and University of Washington Primary Infection Clinic. Study tests included the OraQuick ADVANCE Rapid HIV-1/2 Antibody Test performed on oral fluids and tests performed on fingerstick whole blood specimens including OraQuick, Uni-Gold Recombigen HIV test, Determine HIV-1/2 Ag/Ab Combo, and INSTI HIV-1 Rapid Antibody Test. Specimens from subjects with negative results were sent for EIA and nucleic acid amplification testing. McNemar's exact tests compared the numbers of HIV-infected subjects detected.

RESULTS

Between February 2010 and August 2014, there were 3438 study visits. Twenty-four subjects had discordant POC results with at least one reactive and one non-reactive test, including one subject with a reactive Determine p24 antigen. OraQuick performed on oral fluids identified fewer persons compared to all fingerstick tests. OraQuick performed on fingerstick whole blood detected fewer persons compared to the Determine Combo antibody component (p=.008) and Combo overall (p=.004), and there was a trend when compared to INSTI (p=.06). The Determine Combo specificity was 98.99%.

CONCLUSIONS

As reported by others, Determine Combo underperforms compared to laboratory-based testing, but it did detect one acute infection. If these results are validated, the specificity of Determine Combo may limit its usefulness in populations with lower HIV incidence.

The HIV treatment cascade in acutely infected people: informing global guidelines

PURPOSE OF REVIEW

Acute and early HIV (AHI) is a pivotal time during HIV infection, yet there remain major shortfalls in diagnosis, linkage to care, and antiretroviral therapy (ART) initiation during AHI. We introduce an AHI-specific cascade, review recent evidence pertaining to the unique challenges of AHI, and discuss strategies for improving individual and public health outcomes.

RECENT FINDINGS

Presentation during AHI is common. Expanding use of fourth-generation testing and pooled nucleic acid amplification testing has led to improved AHI detection in resource-wealthy settings. Technologies capable of AHI diagnosis are rare in resource-limited settings; further development of point-of-care devices and utilization of targeted screening is needed. Rapid ART initiation during AHI limits reservoir seeding, preserves immunity, and prevents transmission. Reporting of AHI cascade outcomes is limited, but new evidence suggests that impressive rates of diagnosis, linkage to care, rapid ART initiation, and viral suppression can be achieved.

SUMMARY

With advancements in AHI diagnostics and strong evidence for the therapeutic and prevention benefits of ART initiated during AHI, improving AHI cascade outcomes is both crucial and feasible. HIV guidelines should recommend diagnostic algorithms capable of detecting AHI and prescribe rapid, universal ART initiation during AHI.

HIV infection

More than 75 million people worldwide have been infected with human immunodeficiency virus (HIV), and there are now approximately 37 million individuals living with the infection. Untreated HIV replication causes progressive CD4(+) T cell loss and a wide range of immunological abnormalities, leading to an increased risk of infectious and oncological complications. HIV infection also contributes to cardiovascular disease, bone disease, renal and hepatic dysfunction and several other common morbidities. Antiretroviral drugs are highly effective at inhibiting HIV replication, and for individuals who can access and adhere to these drugs, combination antiretroviral therapy leads to durable (and probably lifelong) suppression of viral replication. Viral suppression enables immune recovery and the near elimination of the risk for developing acquired immune deficiency syndrome (AIDS). Despite effective treatment, HIV-infected individuals have a higher than expected risk of heart, bone, liver, kidney and neurological disease. When used optimally by an infected (or by an uninfected) person, antiretroviral drugs can virtually eliminate the risk of HIV transmission. Despite major advances in prevention sciences, HIV transmission remains common in many vulnerable populations, including men who have sex with men, injection drug users and sex workers. Owing to a lack of widespread HIV testing and the costs and toxicities associated with antiretroviral drugs, the majority of the infected population is not on effective antiretroviral therapy. To reverse the pandemic, improved prevention, treatment and implementation approaches are necessary.