HIV-1 treatment as prevention: the good, the bad, and the challenges

Promoting HIV care continuum outcomes among people who use drugs and alcohol: a systematic review of randomized trials evaluating behavioral HIV care interventions published from 2011 to 2023

BACKGROUND

Substance use remains a robust predictor of HIV infection and a serious impediment to HIV care continuum progression for people living with HIV. The primary research question of this systematic review is focused on understanding the extent to which behavioral HIV care interventions have been efficacious in helping people who live with HIV and who use substances along the HIV care continuum.

METHODS

Using PubMed and ProQuest databases, we performed a systematic review of randomized trials of behavioral HIV care continuum interventions among people who use substances published from 2011 to August 2023, since the beginning of the treatment-as-prevention era.

RESULTS

We identified 11 studies (total participants: N = 5635), ten intentionally targeting substance-using populations. Four studies involved samples using ≥ 1 substance (e.g., alcohol, opioids, stimulants, marijuana); four involved injection drug use; one involved methamphetamine use; and one involved alcohol use. One study targeted a population with incidental substance use (i.e., alcohol, injection drug use, non-injection drug use reported in most participants). Each study defined one or more HIV care outcomes of interest. Viral suppression was an outcome targeted in 9/11 studies, followed by uptake of antiretroviral therapy (ART; 7/11), ART adherence (6/11), retention in care (5/11), and linkage to care (3/11). While most (nine) of the studies found significant effects on at least one HIV care outcome, findings were mostly mixed. Mediated (2/11) and moderated (2/11) effects were minimally examined.

CONCLUSIONS

The results from this systematic review demonstrate mixed findings concerning the efficacy of previous HIV care interventions to improve HIV care continuum outcomes among people who use substances. However, heterogeneity of study components (e.g., diversity of substances used/assessed, self-report vs. objective measures, attrition) prevent broad deductions or conclusions about the amenability of specific substance-using populations to HIV care intervention. More coordinated, comprehensive, and targeted efforts are needed to promote and disentangle intervention effects on HIV care continuum outcomes among substance-using populations.

Substance Use Predicts Sustained Viral Suppression in a Community Cohort of Sexual and Gender Minority Youth Living with HIV

Retention in care and sustained viral suppression are integral outcomes in the care continuum for people living with HIV (PLWH) and HIV prevention; however, less is known about how substance use predicts sustained viral suppression over time. This study seeks to examine the predictive effects of substance use on sustained viral suppression in a sample of cisgender sexual minority men and gender minority PLWH (n = 163) drawn from a longitudinal sample in the Chicago area collected 2015-2019. Using data from 3 visits separated by 6 months, participants were coded persistently detectable, inconsistently virally suppressed, and consistently virally suppressed (< 40 copies/mL at all visits). Multinomial logistic regressions were utilized. About 40% of participants had sustained viral suppression. In multinomial logistic regressions, CUDIT-R predicted persistent detectable status and stimulant use was associated with inconsistent viral suppression. Substance use may create challenges in achieving sustained viral suppression, which has important implications for care and prevention.

Cryptococcus neoformans infection in Human Immunodeficiency Virus (HIV)-infected and HIV-uninfected patients at an inner-city tertiary care hospital in the Bronx

Cryptococcus neoformans causes life-threatening meningoencephalitis. Human immunodeficiency virus (HIV) infection is the most significant predisposing condition, but persons with other immunodeficiency states as well as phenotypically normal persons develop cryptococcosis. We retrospectively reviewed medical records of all patients with a diagnosis of cryptococcosis between 2005 and 2017 at our inner-city medical center in the Bronx, an epicenter of AIDS in New York City, and analyzed demographic data, clinical manifestations, laboratory findings, treatment, and mortality for these patients. In sum, 63% of the cases over this 12-year period occurred in HIV-infected patients. And 61% of the HIV-infected patients were non-adherent with antiretroviral therapy, 10% were newly diagnosed with AIDS, and 4% had unmasking cryptococcus-associated immune reconstitution inflammatory syndrome. The majority were Hispanic or black in ethnicity/race. HIV-uninfected patients (47/126) were older (P < .0001), and the majority had an immunocompromising condition. They were less likely to have a headache (P = .0004) or fever (P = .03), had prolonged time to diagnosis (P = .04), higher cerebrospinal fluid (CSF) glucose levels (P = .001), less CSF culture positivity (P = .03), and a higher 30-day mortality (P = .03). Cases in HIV-uninfected patients were often unsuspected during their initial evaluation, leading to a delay in infectious diseases consultation, which was associated with mortality (P = .03). Our study indicates that HIV infection remains the most important predisposing factor for cryptococcosis despite availability of antiretroviral therapy and highlights potential missed opportunities for earlier diagnosis and differences in clinical and prognostic factors between HIV-infected and HIV-uninfected patients.

Poor quality of life and incomplete self-reported adherence predict second-line ART virological failure in resource-limited settings

We evaluated health-related quality of life (QoL) and self-reported incomplete adherence as predictors of early second-line antiretroviral (ART) virological failure (VF). ACTG A5273 study participants completed the ACTG SF-21 measure which has 8 QoL domains. We used exact logistic regression to assess the association of QoL at baseline and week 4 with early VF adjusted for self-reported adherence. Of 500 individuals (51% women, median age 39 years) in this analysis, 79% and 75% self-reported complete adherence (no missing doses in the past month) at weeks 4 and 24, respectively. Early VF was experienced by 7% and more common among those who self-reported incomplete adherence. Participants with low week 4 QoL scores had higher rates of early VF than participants with high scores. After adjusting for self-reported adherence at week 4, VL and CD4 at baseline, cognitive functioning, pain and mental health domains were significantly associated with subsequent early VF. In this post-hoc analysis, poorer QoL adds to self-reported incomplete adherence after 4 weeks of second-line ART in predicting VF at week 24. Evaluation is needed to assess whether individuals with poorer QoL might be targeted for greater support to reduce risk of VF.Trial registration: ClinicalTrials.gov identifier: NCT01352715.

Willingness to use HIV prevention methods among vaccine efficacy trial participants in Soweto, South Africa: discretion is important

BACKGROUND

Despite multiple available HIV prevention methods, the HIV epidemic continues to affect South Africa the most. We sought to understand willingness to use actual and hypothetical HIV prevention methods among participants enrolled in a preventative HIV vaccine efficacy trial in Soweto, South Africa.

METHODS

We conducted a qualitative study with 38 self-reporting HIV-uninfected and consenting 18-35 year olds participating in the HVTN 702 vaccine efficacy trial in Soweto. Using a semi-structured interview guide, five focus group discussions (FGDs) were held, stratified by age, gender and sexual orientation. The FGDs were composed of: (i) 10 heterosexual women aged 18-24 years; (ii) 9 heterosexual and bisexual women aged 25-35 years; (iii & iv) heterosexual men aged 25-35 years with 7 in both groups; and (v) 5 men aged 18-35 years who have sex with men. FGDs were audio-recorded, transcribed verbatim, translated into English and analysed using thematic analysis.

RESULTS

We present five main themes: (i) long-lasting methods are preferable; (ii) condoms are well-known but not preferred for use; (iii) administration route of HIV prevention method is a consideration for the user; (iv) ideal HIV prevention methods should blend into the lifestyle of the user; and the perception that (v) visible prevention methods indicate sexual indiscretion.

CONCLUSIONS

The participants' candour about barriers to condom and daily oral pre-exposure prophylaxis (PrEP) use, and expressed preferences for long-lasting, discreet, lifestyle-friendly methods reveal a gap in the biomedical prevention market aiming to reduce sexually acquired HIV in South Africa. Product developers should consider long-acting injectable formulations, such as vaccines, passive antibodies and chemoprophylaxis, for HIV prevention technologies. Future innovations in HIV prevention products may need to address the desire for the method to blend easily into lifestyles, such as food-medication formulations.

Factors associated with perceived accuracy of the Undetectable = Untransmittable slogan among men who have sex with men: Implications for messaging scale-up and implementation

INTRODUCTION

Recent research has shown high efficacy of HIV treatment for reducing the risk of HIV transmission to sexual partners. As the efficacy of treatment as prevention (TasP) has proliferated, a new messaging campaign, Undetectable = Untransmittable, has been gaining popularity. The purpose of this paper was to assess factors associated with the perceived accuracy of this TasP messaging strategy among a large and diverse sample of gay, bisexual, and other men who have sex with men (GBMSM) in order to inform subsequent efforts at large-scale and implementation of the HIV prevention message.

METHODS

We conducted a nationwide survey of GBMSM in the U.S. recruited from an online social networking site and a mobile sexual networking app. We analysed data from 12,222 GBMSM separately by HIV status to examine sociodemographic and behavioural factors associated with ratings of the accuracy of the Undetectable = Untransmittable message, which included the option to indicate not understanding what "undetectable" meant.

RESULTS

Among HIV-negative and unknown men, multivariable linear regression indicated that being on pre-exposure prophylaxis (PrEP), identifying as gay or queer (versus bisexual or straight), recent serodiscordant condomless anal sex (CAS), testing every six months or more often, less concern about sexually transmitted infection (STI) infection, and lower perceived risk of HIV infection were the factors with the largest independent effect on rating the Undetectable = Untransmittable statement as more accurate. Fewer factors emerged as associated with accuracy ratings among HIV-positive participants-reporting an undetectable viral load, a lifetime acquired immune deficiency syndrome (AIDS) diagnosis, and lower concern about STI infection were the factors most strongly associated with rating the statement as more accurate.

CONCLUSIONS

The findings of the current study highlight variability in the perceived accuracy of the Undetectable = Untransmittable message, suggesting potential subgroups who might benefit from targeted educational campaigns, perhaps broadcast utilizing sexual networking apps. Numerous factors, particularly among HIV-negative and unknown GBMSM, were associated with rating the message as more accurate. In particular, being on PrEP and testing regularly were two of the variables most strongly associated with higher accuracy ratings among HIV-negative GBMSM, suggesting HIV prevention services as potential points of intervention for increasing HIV knowledge and decreasing HIV stigma.

Weighing the Evidence of Efficacy of Oral PrEP for HIV Prevention in Women in Southern Africa

As oral tenofovir-based regimens for preexposure prophylaxis (PrEP) are adopted as standard of care for HIV prevention, their utilization in clinical trials among women in southern Africa will require an accurate estimate of oral PrEP efficacy in this population. This information is critical for women in choosing this prevention strategy, and in public health policy making. Estimates of the efficacy of oral PrEP regimens containing tenofovir have varied widely across trials that enrolled women, with some studies reporting high efficacy and others reporting no efficacy. Although poor adherence is strongly associated with lack of efficacy, other factors, such as mode of transmission (sexual vs. parenteral), predominant HIV subtype (C vs. non-C), intensity of exposure, and percentage of stable serodiscordant couples, may also contribute to the variation in efficacy estimates. In this article, we evaluate the evidence for PrEP efficacy in women and propose potential explanations for the observed differences in efficacy among studies. Our review emphasizes the need to continue to refine estimates of efficacy and effectiveness of tenofovir-based oral PrEP so as to best develop the next generation of HIV prevention tools, and to inform public policies directed toward HIV prevention.

Prosecution of non-disclosure of HIV status: Potential impact on HIV testing and transmission among HIV-negative men who have sex with men

Background

Non-disclosure criminal prosecutions among gay, bisexual and other men who have sex with men (MSM) are increasing, even though transmission risk is low when effective antiretroviral treatment (ART) is used. Reduced HIV testing may reduce the impact of HIV “test and treat” strategies. We aimed to quantify the potential impact of non-disclosure prosecutions on HIV testing and transmission among MSM.

Methods

MSM attending an HIV and primary care clinic in Toronto completed an audio computer-assisted self-interview questionnaire. HIV-negative participants were asked concern over non-disclosure prosecution altered their likelihood of HIV testing. Responses were characterized using cross-tabulations and bivariate logistic regressions. Flow charts modelled how changes in HIV testing behaviour impacted HIV transmission rates controlling for ART use, condom use and HIV status disclosure.

Results

150 HIV-negative MSM were recruited September 2010 to June 2012. 7% (9/124) were less or much less likely to be tested for HIV due to concern over future prosecution. Bivariate regression showed no obvious socio/sexual demographic characteristics associated with decreased willingness of HIV testing to due concern about prosecution. Subsequent models estimated that this 7% reduction in testing could cause an 18.5% increase in community HIV transmission, 73% of which was driven by the failure of HIV-positive but undiagnosed MSM to access care and reduce HIV transmission risk by using ART.

Conclusions

Fear of prosecution over HIV non-disclosure was reported to reduce HIV testing willingness by a minority of HIV-negative MSM in Toronto; however, this reduction has the potential to significantly increase HIV transmission at the community level which has important public health implications.

Measures of human immunodeficiency virus (HIV) community viral load and HIV incidence among people who inject drugs

PURPOSE

To evaluate the measures of community human immunodeficiency virus (HIV) viral load (VL) and the association with HIV incidence among people who inject drugs (PWID).

METHODS

Data were from 1986 to 1999 Urban Health Study conducted among PWID in the San Francisco Bay Area. Extant measures of community VL use mean VL among HIV + study participants, not accounting for the proportion of HIV- individuals. We compared the strength of the associations between HIV incidence and the traditionally measured mean community VL and a new prevalence-adjusted community VL, calculated by dividing the sum of VL among HIV + participants by the total participants irrespective of HIV status.

RESULTS

Mean community VL was not correlated with HIV incidence in this sample of PWID (rs = 0.32, P = .28). However, prevalence-adjusted community VL was strongly correlated with HIV incidence (rs = 0.69, P = .009). Nested complimentary log-log linear models indicated that increases in community VL and prevalence-adjusted community VL were both associated with HIV incidence, but prevalence-adjusted community VL was a more sensitive measure (hazard ratio = 1.28, P = .038 and hazard ratio = 3.29, P < .001, respectively).

CONCLUSIONS

The effect of community VL on HIV incidence may be stronger than previously reported. Future studies of community VL surveillance should consider accounting for the prevalence of HIV using a prevalence-adjusted community VL measure.

Psychosocial Functioning and Decisional Balance to Use Condoms in a Racially/Ethnically Diverse Sample of Young Gay/Bisexual Men Who Have Sex with Men

Young gay/bisexual and other men who have sex with men (YGBMSM; ages 18-24) are experiencing an increase in HIV infection rates, particularly if they are Black or Latino. Psychosocial functioning is consistently implicated in HIV risk behaviors; however, less is known about the role of these factors in YGBMSM's decision-making process to use condoms (i.e., decisional balance to use condoms; DBC). We examined whether YGBMSM's psychological functioning was associated differentially with their DBC across racial/ethnic groups. Using data from a cross-sectional web-survey of single YGBMSM (N = 1380; 9.9% Black; 18.6% Latino; 71.5% White), we performed racial/ethnic-specific multivariable regression models to explore the association between DBC and psychological factors (e.g., depression, anxiety), demographics (e.g., age, education, HIV status, prior STI diagnosis), and perceived difficulty implementing safer sex strategies. Black YGBMSM reported lower DBC if they reported higher depression symptoms (β = -.31, p < .05), were HIV-negative (β = -.20, p < .05), and had greater difficulty implementing safer sex strategies (β = -.32, p < .001). Latino participants reported greater DBC to use condoms if they reported greater anxiety symptoms (β = .21, p < .05). White participants reported greater DBC if they were younger (β = -.09, p < .01), did not report a prior STI (β = .10, p < .001), and had fewer difficulties implementing safer sex strategies (β = -.27, p < .001); DBC had no association to psychological well-being among White participants. Psychological factors may be differentially associated with DBC across racial/ethnic group categories. Health promotion initiatives targeting condom use may benefit from culturally tailored interventions that address psychosocial functioning and its role in YGBMSM's condom use decision-making.

Adherence to antiretroviral therapy among HIV/ AIDS patients in the context of early treatment initiation in Vietnam

PURPOSE

This study aimed to assess the antiretroviral therapy (ART) compliance among patients with HIV/AIDS and its associated factors in the context of universal ART initiation in Vietnam.

PATIENTS AND METHODS

A cross-sectional survey was conducted in five ART clinics located in three provinces, such as Hanoi, Thanh Hoa, and Lao Cai, from July to September 2017. Overall, adherence to ART in the last month was measured using a 100-point Visual Analog Scale (VAS). Besides, information about forgetting doses in the last 4 days and delaying taking pills in the last 7 days was also reported.

RESULTS

Among 482 patients, the suboptimal adherence rate was 54.5%. Noncurrent smoking (coefficient =4.19, 95% CI 0.42-7.97), higher baseline CD4 count (coefficient =4.35, 95% CI 0.58-8.13), and no traveling difficulties (coefficient =6.17, 95% CI 2.27-10.06) were predictors of higher VAS adherence score. Suboptimal adherence was associated with mountainous residence (OR =5.34, 95% CI 2.81-10.16). Female respondents were less likely to delay taking pills in the last 7 days (OR =0.19, 95% CI 0.07-0.52).

CONCLUSION

Our study embraced early ART initiation in Vietnam; however, this approach should be parallel with appropriate resource allocation and service delivery.

Hypo-osmolar Formulation of Tenofovir (TFV) Enema Promotes Uptake and Metabolism of TFV in Tissues, Leading to Prevention of SHIV/SIV Infection

Oral preexposure prophylaxis (PrEP) has been approved for prophylaxis of HIV-1 transmission but is associated with high costs and issues of adherence. Protection from anal transmission of HIV using topical microbicides and methods congruent with sexual behavior offers the promise of improved adherence. We compared the pharmacokinetics (PK) and ex vivo efficacy of iso-osmolar (IOsm) and hypo-osmolar (HOsm) rectal enema formulations of tenofovir (TFV) in rhesus macaques. Single-dose PK of IOsm or HOsm high-dose (5.28 mg/ml) and low-dose (1.76 mg/ml) formulations of TFV enemas were evaluated for systemic uptake in blood, colorectal biopsy specimens, and rectal CD4⁺ T cells. Markedly higher TFV concentrations were observed in plasma and tissues after administration of the HOsm high-dose formulation than with all other formulations tested. TFV and TFV diphosphate (TFV-DP) concentrations in tissue correlated for the HOsm high-dose formulation, demonstrating rapid uptake and transformation of TFV to TFV-DP in tissues. TFV-DP amounts in tissues collected at 1 and 24 h were 7 times and 5 times higher, respectively (P < 0.01), than the ones collected in tissues with the IOsm formulation. The HOsm high-dose formulation prevented infection in ex vivo challenges of rectal tissues collected at 1, 24, and 72 h after the intrarectal dosing, whereas the same TFV dose formulated as an IOsm enema was less effective.

HIV care and treatment experiences among female sex workers living with HIV in sub-Saharan Africa: A systematic review

Female sex workers (FSW) living with HIV in sub-Saharan Africa have poor engagement to HIV care and treatment. Understanding the HIV care and treatment engagement experiences of FSW has important implications for interventions to enhance care and treatment outcomes. We conducted a systematic review to examine the HIV care experiences and determinants of linkage and retention in care, antiretroviral therapy (ART) initiation, and ART adherence and viral suppression among FSW living with HIV in sub-Saharan Africa. The databases PubMed, Embase, Web of Science, SCOPUS, CINAHL, Global Health, Psycinfo, Sociological Abstracts, and Popline were searched for variations of search terms related to sex work and HIV care and treatment among sub-Saharan African populations. Ten peer-reviewed articles published between January 2000 and August 2015 met inclusion criteria and were included in this review. Despite expanded ART access, FSW in sub-Saharan Africa have sub-optimal HIV care and treatment engagement outcomes. Stigma, discrimination, poor nutrition, food insecurity, and substance use were commonly reported and associated with poor linkage to care, retention in care, and ART initiation. Included studies suggest that interventions with FSW should focus on multilevel barriers to engagement in HIV care and treatment and explore the involvement of social support from intimate male partners. Our results emphasise several critical points of intervention for FSW living with HIV, which are urgently needed to enhance linkage to HIV care, retention in care, and treatment initiation, particularly where the HIV prevalence among FSW is greatest.

Epidemiological impact of achieving UNAIDS 90-90-90 targets for HIV care in India: a modelling study

OBJECTIVE

Recent UNAIDS '90-90-90' targets propose that to end the HIV epidemic by 2030, 90% of persons living with HIV (PLWH) worldwide should know their diagnosis, 90% of diagnosed PLWH should be on antiretroviral therapy (ART) and 90% of PLWH on ART should be virally suppressed by 2020. We sought to quantify the epidemiological impact of achieving these targets in India.

METHODS

We constructed a dynamic-transmission model of the Indian HIV epidemic to project HIV infections and AIDS-related deaths that would occur in India over 15 years. We considered several scenarios: continuation of current care engagement (with early ART initiation), achieving 90-90-90 targets on time and delaying achievement by 5 or 10 years.

RESULTS

In the base case, assuming continuation of current care engagement, we project 794 000 (95% uncertainty range (UR) 571 000-1 104 000) HIV infections and 689 000 (95% UR 468 000-976 000) AIDS-related deaths in India over 15 years. In this scenario, nearly half of PLWH diagnosed would fail to achieve viral suppression by 2030. With achievement of 90-90-90 targets, India could avert 392 000 (95% UR 248 000-559 000) transmissions (48% reduction) and 414 000 (95% UR 260 000-598 000) AIDS-related deaths (59% reduction) compared to the base-case scenario. Furthermore, fewer than 20 000 (95% UR 12 000-30 000) HIV infections would occur in 2030. Delaying achievement of targets resulted in a similar reduction in HIV incidence by 2030 but at the cost of excess overall infections and mortality.

CONCLUSIONS

India can halve the epidemiological burden of HIV over 15 years with achievement of the UNAIDS 90-90-90 targets. Reaching the targets on time will require comprehensive healthcare strengthening, especially in early diagnosis and treatment, expanded access to second-line and third-line ART and long-term retention in care.

HIV testing and engagement in care among highly vulnerable female sex workers: implications for treatment as prevention models

BACKGROUND

Although emerging Treatment as Prevention models can be effective in reducing HIV incidence among high-risk populations, many HIV infected individuals remain undiagnosed or fail to engage in HIV care.

METHODS

This study examined the factors associated with HIV testing and care among a population of substance using female sex workers.

RESULTS

Recent HIV testing was associated with higher education level, having a regular health care provider or clinic, recent crack use, and higher sexual risk behaviors; HIV treatment utilization was associated with higher levels of social support, having a regular health care provider or clinic, housing stability and insurance coverage. Qualitative data revealed HIV-related stigma, denial, social isolation, and substance use as barriers to HIV testing and treatment; social support and accessibility of services were key enablers.

CONCLUSIONS

Improving HIV testing and linkage to treatment among female sex workers will require structural initiatives to reduce stigma and increase service seeking support.

A practical online tool to estimate antiretroviral coverage for HIV infected and susceptible populations needed to reduce local HIV epidemics

It remains unclear what proportions of HIV-infected and uninfected people should receive effective antiretroviral therapy (ART) to control local HIV epidemics. We developed a flexible model to evaluate the impact of treatment as prevention (TasP) and pre-exposure prophylaxis (PrEP) on HIV incidence in local communities. We evaluated this tool for determining what TasP and PrEP targets are needed to substantially reduce the HIV epidemic in San Diego, which is predominately comprised of men who have sex with men. By increasing the proportion of HIV-infected individuals on ART from 30% to 50%, 686 new infections would be prevented over five years in San Diego. By providing PrEP to 30% of MSM to the age group that account for 90% of local HIV incident cases (21-52 years), we could prevent 433 infections over five years. When combining these initiatives, a PrEP coverage rate of 40% and TasP coverage rate of 34% would be expected to decrease the number of new infections by over half in one year. This online tool is designed to help local public health planners and policy makers to estimate program outcomes and costs that may lead to better control of their local HIV epidemics.

Willingness to Act upon Beliefs about 'Treatment as Prevention' among Australian Gay and Bisexual Men

HIV ‘treatment as prevention’ (TasP) is highly effective in reducing HIV transmission in serodiscordant couples. There has been little examination of gay and bisexual men’s attitudes towards TasP, particularly regarding men’s willingness to act on beliefs about TasP. We conducted an online cross-sectional survey of Australian men in late 2012 to investigate knowledge and beliefs about new developments in HIV prevention. Amongst 839 men (mean age 39.5 years), men tended to disagree that TasP was sufficiently effective to justify reduced condom use, although HIV-positive men had more favourable attitudes. Only a minority of men were aware of any evidence for TasP; and one-quarter incorrectly believed that evidence for the effectiveness of TasP already existed for the homosexual population. One-fifth (20.5%) of men reported that they would be willing to have condomless anal intercourse with an opposite-status sexual partner when the HIV-positive partner was taking HIV treatments. Factors independently associated with such willingness were: HIV-positive serostatus, reporting any serodiscordant or serononconcordant condomless anal intercourse with a regular male partner in the previous six months, reporting any condomless anal intercourse with a casual male partner in the previous six months, and having greater beliefs in the effectiveness of TasP. This indicated that the men most willing to rely on TasP to prevent transmission were already engaging in higher risk practices. Biomedical HIV prevention represents a rapidly changing environment with new research as well as community and policy responses emerging at a fast pace. For men with serodiscordant sexual partners to successfully apply TasP to reducing transmission risk, more support and education is needed to enable better utilisation of TasP in specific relational and sexual contexts.

The indirect impact of antiretroviral therapy: Mortality risk, mental health, and HIV-negative labor supply

To reduce the burden of the HIV/AIDS epidemic, international donors recently began providing free antiretroviral therapy (ART) in parts of Sub-Saharan Africa. ART dramatically prolongs life and reduces infectiousness for people with HIV. This paper shows that ART availability increases work time for HIV-negative people without caretaker obligations, who do not directly benefit from the medicine. A difference-in-difference design compares people living near and far from ART, before and after treatment becomes available. Next we explore the possible reasons for this pattern. Although we cannot pinpoint the mechanism, we find that ART availability substantially reduces subjective mortality risk and improves mental health. These results show an undocumented economic consequence of the HIV/AIDS epidemic and an important externality of medical innovation. They also provide the first evidence of a link between the disease environment and mental health.

Evaluating the Impact of Test-and-Treat on the HIV Epidemic among MSM in China Using a Mathematical Model

Background

Various studies have modeled the impact of test-and-treat policies on the HIV epidemics worldwide. However, few modeling studies have taken into account China’s context. To understand the potential effect of test-and-treat on the HIV epidemic among men who have sex with men (MSM) in China, we developed a mathematical model to evaluate the impact of the strategy.

Method

Based on the natural history of the CD4 count of people living with HIV and AIDS (PLWHA), we constructed a dynamic compartmental model of HIV transmission among Chinese MSM to project the number of HIV new infections and prevalence over 10 years. We predicted the annual number of HIV new infections and the total number of MSM living with HIV and AIDS (based on Beijing data) between 2010 and 2022 under the following conditions: (1) current practice (testing rate of 50% and ART coverage of 39%); (2) both testing rate and ART coverage increasing to 70% in 2013; (3) both testing rate and ART coverage increasing to 90% in 2013; and (4) both testing rate and ART coverage increasing gradually every year until 90% since 2013.

Results

Based on our model, if the HIV test-and-treat policy was implemented among Chinese MSM, the total number of HIV new infections over 10 years (2013-2022) would be reduced by 50.6-70.9% compared with the current policy. When ART coverage for PLWHA increased to 58% since 2013, the ‘turning point’ would occur on the curve of HIV new infections by 2015. A 25% reduction in annual number of HIV new infections by 2015 might be achieved if the testing rate increased from 50% to 70% and treatment coverage for PLWHA increased to 55% since 2013.

Conclusion

Implementation of the test-and-treat strategy may significantly reduce HIV new infections among MSM in China. Great efforts need to be made to scale up HIV testing rate and ART coverage among Chinese MSM.

Effects of syndemics on HIV viral load and medication adherence in the multicentre AIDS cohort study

OBJECTIVES

The objective of this study is to determine associations between intertwining epidemics (syndemics) and HIV medication adherence and viral load levels among HIV-positive MSM and to test whether adherence mediates the relationship between syndemics and viral load.

DESIGN

We analysed participant data collected between 2003 and 2009 from the Multicenter AIDS Cohort Study, a prospective HIV/AIDS cohort study in four U.S. cities.

METHODS

We conducted longitudinal analyses (repeated measures mixed models) to assess whether differences in viral load levels, undetectable viral load and self-reported HIV medication adherence were associated with count of syndemic conditions (substance use, depression symptoms and sexual risk behaviour, range 0-3), adjusting for race/ethnicity, age and income. Mediation analyses were conducted using structural equation modelling and the SAS %mediate macro.

RESULTS

Syndemics count was associated with higher viral loads (P < 0.0001) and lower adherence (P < 0.0001). Increased counts of concomitant syndemics were associated with viral load (P < 0.01), detectable viral load (P < 0.05) and adherence (P < 0.001). Black MSM experienced worse outcomes across domains than white MSM (P < 0.0001) and experienced higher overall rates of syndemics (P < 0.01). Adherence significantly mediated the relationship between syndemics and viral load, accounting for an estimated 32.3% of the effect (P < 0.05).

CONCLUSION

Effectively lowering viral load levels among MSM has implications for both HIV/AIDS prevention and care. Our findings suggest that integrating substance use interventions, mental healthcare and sexual risk prevention into standard HIV care may be necessary to optimize treatment and Treatment as Prevention (TasP) models.

HIV-Risk Reduction with Juvenile Offenders on Probation

Youth involved in the juvenile justice system are at elevated risk for HIV as a result of high rates of sexual risk taking, substance use, mental health problems and sexually transmitted infections. Yet few HIV prevention programs exist for young offenders. This pilot study examined change in juvenile offenders' sexual activity, drug/alcohol use, HIV testing and counseling, and theoretical mediators of risk taking following participation in PHAT Life, an HIV-prevention program for teens on probation. Participants (N=54) were 13-17 year-old arrested males and females remanded to a detention alternative setting. Youth participated in a uniquely tailored HIV prevention intervention and completed a baseline and 3-month follow up assessment of their HIV and substance use knowledge, attitudes, beliefs, and behaviors. At 3-month follow up, teens reported less alcohol use, more positive attitudes toward peers with HIV, greater ability to resist temptation to use substances, and for males, improved HIV prevention self-efficacy and peer norms supporting prevention. Teens were also more likely to seek HIV counseling and males were more likely to get tested for HIV. Effect sizes revealed moderate change in sexual behavior. Findings support PHAT Life as a promising intervention to reduce HIV-risk among youth in juvenile justice.

Global HIV epidemiology: A guide for strategies in prevention and care

Global trends in HIV incidence are estimated typically by serial prevalence surveys in selected sentinel populations or less often in representative population samples. Incidence estimates are often modeled because cohorts are costly to maintain and are rarely representative of larger populations. From global trends, we can see reason for cautious optimism. Downward trends in generalized epidemics in Africa, concentrated epidemics in persons who inject drugs (PWID), some female sex worker cohorts, and among older men who have sex with men (MSM) have been noted. However, younger MSM and those from minority populations, as with black MSM in the United States, show continued transmission at high rates. Among the many HIV prevention strategies, current efforts to expand testing, linkage to effective care, and adherence to antiretroviral therapy are known as "treatment as prevention" (TasP). A concept first forged for the prevention of mother to child transmission, TasP generates high hopes that persons treated early will derive considerable clinical benefits and that lower infectiousness will reduce transmission in communities. With the global successes of risk reduction for PWID, we have learned that reducing marginalization of the at-risk population, implementation of nonjudgmental and pragmatic sterile needle and syringe exchange programs, and offering of opiate substitution therapy to help persons eschew needle use altogether can work to reduce the HIV epidemic. Never has the urgency of stigma reduction and guarantees of human rights been more urgent; a public health approach to at-risk populations requires that to avail themselves of prevention services and they must feel welcomed.

The Opposites Attract Study of viral load, HIV treatment and HIV transmission in serodiscordant homosexual male couples: design and methods

BACKGROUND

Studies in heterosexual HIV serodiscordant couples have provided critical evidence on the role of HIV treatments and undetectable viral load in reducing the risk of HIV transmission. There is very limited data on the risk of transmission from anal sex in homosexual male serodiscordant couples.

METHODS/DESIGN

The Opposites Attract Study is an observational prospective longitudinal cohort study of male homosexual serodiscordant partnerships running from 2012 to 2015 and conducted in clinics throughout Australia, Brazil and Thailand. Couples attend two or more clinic visits per year. The HIV-positive partner's viral load is tested and the HIV-negative partner is tested for HIV antibodies at every clinic visit. Results from any tests for sexually transmitted infections are also collected. Detailed behavioural questionnaires are completed by both partners at the time of each visit. The primary research question is whether HIV incidence is lower in those couples where the HIV-positive partner is receiving HIV treatment compared to couples where he is not receiving treatment. A voluntary semen sub-study will examine semen plasma viral load in a subsample of HIV-positive partners in Sydney, Rio de Janeiro and Bangkok. In cases of seroconversion of the initially HIV-negative partner, phylogenetic analysis will be conducted at the end of the study on virus from stored blood samples from both partners to determine if the infection came from the HIV-positive study partner. Men in new serodiscordant relationships will specifically be targeted for recruitment.

DISCUSSION

This study will provide critical data on the reduction in HIV transmission risk associated with being on HIV treatment in homosexual male serodiscordant couples in different regions of the world. Data from men in new relationships will be particularly valuable given that the highest transmission risk is in the first year of serodiscordant relationships. Furthermore, the detailed behavioural and attitudinal data from the participant questionnaires will allow exploration of many contextual factors associated with HIV risk, condom use and the negotiation of sexual practice within couples.

Alcohol and drug use outcomes among vulnerable women living with HIV: results from the Western Cape Women's Health CoOp

Alcohol and other drug use can negatively affect adherence to and retention in antiretroviral therapy (ART) among people living with HIV/AIDS. Yet, there are few brief interventions that reduce these behaviors among this population. This article presents the findings from a randomized field experiment that assessed the effects of a woman-focused intervention (the Women's Health CoOp [WHC]) on reducing alcohol and other drug use among vulnerable women in Cape Town, South Africa. The analyses were limited to 84 women living with HIV who reported drinking alcohol at baseline. Because of the small sample size, analyses were performed using an exact logistic regression procedure. At 12-month follow-up, women in the WHC arm were more likely to be abstinent from alcohol (odds ratio [OR] = 3.61; 95% confidence intervals [CI] = 1.23, 11.70; p = 0.016) and somewhat more likely to test negative for other drugs (OR = 3.07; 95% CI = 0.83, 12.31; p = 0.105), compared with women in the comparison arms. This study provides preliminary evidence of the efficacy of a brief, woman-focused intervention in reducing alcohol and other drug use among vulnerable women living with HIV and it has implications for HIV treatment.

Treatment as prevention: are Argentinean HIV care providers willing to adopt earlier antiretroviral therapy?

HIV guidelines increasingly recommend antiretroviral therapy (ART) initiation at a higher CD4 levels. The extent to which these evolving standards are translated into routine clinical care has not been evaluated in Argentina. During October 2012, we conducted an online survey among Argentinean HIV clinicians to assess their attitudes and practices toward ART initiation and its potential use for HIV prevention. Of the 280 physicians included, 61% would prescribe ART at CD4 ≤ 500 cells/µL for asymptomatic patients. Although, only 11% would recommend ART irrespective of CD4 cell count, 72% would do it for serodiscordant couples, and 75% for sex workers. Most participants agreed that they would consider earlier initiation of ART if transmission risk exists, and that expansion of ART could help decrease HIV incidence. These results suggest that a large proportion of Argentinean HIV care providers are willing to adopt the recently updated Argentinean guidelines recommending earlier ART, especially when high HIV transmission risk exists.

Disparities in HIV transmission risk among HIV-infected black and white men who have sex with men, United States, 2009

OBJECTIVE

To better understand why HIV incidence is substantially higher among black than white men who have sex with men (MSM), we present the first nationally representative estimates of factors that contribute to transmission - sexual behavior, antiretroviral therapy (ART) use, and viral suppression - among HIV-infected black and white MSM in the United States.

DESIGN

The Medical Monitoring Project (MMP) is a complex sample survey of HIV-infected adults receiving medical care in the United States.

METHODS

We used weighted interview and medical record data collected during June 2009 to May 2010 to estimate the prevalence of sexual behaviors, ART use, and viral suppression among sexually active HIV-infected black and white MSM. We used χ tests to assess significant differences between races and logistic regression models to identify factors that mediated the racial differences.

RESULTS

Sexual risk behaviors among black and white MSM were similar. Black MSM were significantly less likely than white MSM to take ART (80 vs. 91%) and be durably virally suppressed (48 vs. 69%). Accounting for mediators (e.g. age, insurance, poverty, education, time since diagnosis, and disease stage) reduced, but did not eliminate, disparities in ART use and rendered differences in viral suppression among those on ART insignificant.

CONCLUSION

Lower levels of ART use and viral suppression among HIV-infected black MSM may increase the likelihood of HIV transmission. Addressing the patient-level factors and structural inequalities that contribute to lower levels of ART use and viral suppression among this group will improve clinical outcomes and might reduce racial disparities in HIV incidence.

Incorporating couples-based approaches into HIV prevention for gay and bisexual men: opportunities and challenges

Thirty years after the beginning of the HIV epidemic, gay, bisexual, and other men who have sex with men (collectively called MSM) bear a disproportionate burden of HIV in the United States and continue to acquire a distressingly high number and proportion of new infections. Historically, HIV prevention for MSM has been focused on individual-level behavior change, rarely intervening with MSM as part of a couple. Yet, an estimated 33–67% of HIV infections among MSM are acquired from primary sexual partners, suggesting that work with MSM as couples could be an important contributor to prevention. Given the emergence of high impact combination HIV prevention, it is timely to consider how work with the broad variety of male couples can improve both personal and community health. Couples HIV testing and counseling for MSM is an important advance for identifying men who are unaware that they are HIV-positive, identifying HIV-discordant couples, and supporting men who want to learn their HIV status with their partner. Once men know their HIV status, new advances in biomedical prevention, which can dramatically reduce risk of HIV transmission or acquisition, allow men to make prevention decisions that can protect themselves and their partners. This paper highlights the present-day challenges and benefits of using a couples-based approach with MSM in the era of combination prevention to increase knowledge of HIV status, increase identification of HIV discordant couples to improve targeting prevention services,and support mutual disclosure of HIV status.

Antiretroviral treatment of HIV-1 prevents transmission of HIV-1: where do we go from here?

Antiretroviral drugs that inhibit viral replication were expected to reduce transmission of HIV by lowering the concentration of HIV in the genital tract. In 11 of 13 observational studies, antiretroviral therapy (ART) provided to an HIV-infected index case led to greatly reduced transmission of HIV to a sexual partner. In the HPTN 052 randomised controlled trial, ART used in combination with condoms and counselling reduced HIV transmission by 96·4%. Evidence is growing that wider, earlier initiation of ART could reduce population-level incidence of HIV. However, the full benefits of this strategy will probably need universal access to very early ART and excellent adherence to treatment. Challenges to this approach are substantial. First, not all HIV-infected individuals can be located, especially people with acute and early infection who are most contagious. Second, the ability of ART to prevent HIV transmission in men who have sex with men (MSM) and people who use intravenous drugs has not been shown. Indeed, the stable or increased incidence of HIV in MSM in some communities where widespread use of ART has been established emphasises the concern that not enough is known about treatment as prevention for this crucial population. Third, although US guidelines call for immediate use of ART, such guidelines have not been embraced worldwide. Some experts do not believe that immediate or early ART is justified by present evidence, or that health-care infrastructure for this approach is sufficient. These concerns are very difficult to resolve. Ongoing community-based prospective trials of early ART are likely to help to establish the population-level benefit of ART, and-if successful-to galvanise treatment as prevention.

Can combination prevention strategies reduce HIV transmission in generalized epidemic settings in Africa? The HPTN 071 (PopART) study plan in South Africa and Zambia

The HIV Prevention Trials Network (HPTN) is conducting the HPTN 071 (PopART) study in 21 communities in Zambia and South Africa with support from a consortium of funders. HPTN 071 (PopART) is a community-randomized trial of a combination prevention strategy to reduce HIV incidence in the context of the generalized epidemic of southern Africa. The full PopART intervention strategy is anchored in home-based HIV testing and facilitated linkage of HIV-infected persons to care through community health workers and universal antiretroviral therapy for seropositive persons regardless of CD4+ cell count or HIV viral load. To further reduce the risk of HIV acquisition among uninfected individuals, the study aims to expand voluntary medical male circumcision, diagnosis and treatment of sexually transmitted infections, behavioral counseling, and condom distribution. The full PopART intervention strategy also incorporates promotion of other interventions designed to reduce HIV and tuberculosis transmission, including optimization of the prevention of mother-to-child HIV transmission and enhanced individual and public health tuberculosis services. Success for the PopART strategy depends on the ability to increase coverage for the study interventions whose uptake is a necessary antecedent to a prevention effect. Processes will be measured to assess the degree of penetration of the interventions into the communities. A randomly sampled population cohort from each community will be used to measure the impact of the PopART strategy on HIV incidence over 3 years. We describe the strategy being tested and progress to date in the HPTN 071 (PopART) study.

Translation of biomedical prevention strategies for HIV: prospects and pitfalls

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

Future of phylogeny in HIV prevention

The success of the HIV Prevention Trials Network 052 trial has led to revisions in HIV-1 treatment guidelines. Antiretroviral therapy may reduce the risk of HIV-1 transmissions at the population level. The design of successful treatment as prevention interventions will be predicated on a comprehensive understanding of the spatial, temporal, and biological dynamics of heterosexual men who have sex with men and intravenous drug user epidemics. Viral phylogenetics can capture the underlying structure of transmission networks based on the genetic interrelatedness of viral sequences and cluster networks that could not be otherwise identified. This article describes the phylogenetic expansion of the Montreal men who have sex with men epidemic over the last decade. High rates of coclustering of primary infections are associated with 1 infection leading to 13 onward transmissions. Phylogeny substantiates the role of primary and recent stage infection in transmission dynamics, underlying the importance of timely diagnosis and immediate antiretroviral therapy initiation to avert transmission cascades.

Combination prevention: new hope for stopping the epidemic

HIV research has identified approaches that can be combined to be more effective in transmission reduction than any 1 modality alone: delayed adolescent sexual debut, mutual monogamy or sexual partner reduction, correct and consistent condom use, pre-exposure prophylaxis with oral antiretroviral drugs or vaginal microbicides, voluntary medical male circumcision, antiretroviral therapy (ART) for prevention (including prevention of mother to child HIV transmission [PMTCT]), treatment of sexually transmitted infections, use of clean needles for all injections, blood screening prior to donation, a future HIV prime/boost vaccine, and the female condom. The extent to which evidence-based modalities can be combined to prevent substantial HIV transmission is largely unknown, but combination approaches that are truly implementable in field conditions are likely to be far more effective than single interventions alone. Analogous to PMTCT, "treatment as prevention" for adult-to-adult transmission reduction includes expanded HIV testing, linkage to care, antiretroviral coverage, retention in care, adherence to therapy, and management of key co-morbidities such as depression and substance use. With successful viral suppression, persons with HIV are far less infectious to others, as we see in the fields of sexually transmitted infection control and mycobacterial disease control (tuberculosis and leprosy). Combination approaches are complex, may involve high program costs, and require substantial global commitments. We present a rationale for such investments and cite an ongoing research agenda that seeks to determine how feasible and cost-effective a combination prevention approach would be in a variety of epidemic contexts, notably that in a sub-Saharan Africa.

Clinical uncertainties, health service challenges, and ethical complexities of HIV "test-and-treat": a systematic review

Despite the HIV "test-and-treat" strategy's promise, questions about its clinical rationale, operational feasibility, and ethical appropriateness have led to vigorous debate in the global HIV community. We performed a systematic review of the literature published between January 2009 and May 2012 using PubMed, SCOPUS, Global Health, Web of Science, BIOSIS, Cochrane CENTRAL, EBSCO Africa-Wide Information, and EBSCO CINAHL Plus databases to summarize clinical uncertainties, health service challenges, and ethical complexities that may affect the test-and-treat strategy's success. A thoughtful approach to research and implementation to address clinical and health service questions and meaningful community engagement regarding ethical complexities may bring us closer to safe, feasible, and effective test-and-treat implementation.

Examining the evidence on the causal effect of HAART on transmission of HIV using the Bradford Hill criteria

In recent years, evidence has accumulated regarding the ability of HAART to prevent HIV transmission. Early supportive evidence was derived from observational, ecological and population-based studies. More recently, a randomized clinical trial showed that immediate use of HAART led to a 96% decrease in HIV transmission events within HIV serodiscordant heterosexual couples. However, the generalizability of the effect of HAART, and the population-level impact on HIV transmission continues to generate substantial debate. We, therefore, conducted a review of the evidence regarding the preventive effect of HAART on HIV transmission within the context of the Bradford Hill criteria for causality. Taken together, we find the accumulated evidence supporting HIV treatment as prevention meets each of the Bradford Hill criteria for causality. We conclude that the opportunity cost of inaction while waiting for additional evidence on the generalizability of effect in other risk groups is too high. Efforts should be redoubled to mobilize the financial capital and political will to optimize implementation of HIV Treatment as Prevention strategies on a wide scale.

High coverage of ART associated with decline in risk of HIV acquisition in rural KwaZulu-Natal, South Africa

The landmark HIV Prevention Trials Network (HPTN) 052 trial in HIV-discordant couples demonstrated unequivocally that treatment with antiretroviral therapy (ART) substantially lowers the probability of HIV transmission to the HIV-uninfected partner. However, it has been vigorously debated whether substantial population-level reductions in the rate of new HIV infections could be achieved in "real-world" sub-Saharan African settings where stable, cohabiting couples are often not the norm and where considerable operational challenges exist to the successful and sustainable delivery of treatment and care to large numbers of patients. We used data from one of Africa's largest population-based prospective cohort studies (in rural KwaZulu-Natal, South Africa) to follow up a total of 16,667 individuals who were HIV-uninfected at baseline, observing individual HIV seroconversions over the period 2004 to 2011. Holding other key HIV risk factors constant, individual HIV acquisition risk declined significantly with increasing ART coverage in the surrounding local community. For example, an HIV-uninfected individual living in a community with high ART coverage (30 to 40% of all HIV-infected individuals on ART) was 38% less likely to acquire HIV than someone living in a community where ART coverage was low (<10% of all HIV-infected individuals on ART).

Systems mapping of HIV-1 infection

Mathematical models of viral dynamics in vivo provide incredible insights into the mechanisms for the nonlinear interaction between virus and host cell populations, the dynamics of viral drug resistance, and the way to eliminate virus infection from individual patients by drug treatment. The integration of these mathematical models with high-throughput genetic and genomic data within a statistical framework will raise a hope for effective treatment of infections with HIV virus through developing potent antiviral drugs based on individual patients’ genetic makeup. In this opinion article, we will show a conceptual model for mapping and dictating a comprehensive picture of genetic control mechanisms for viral dynamics through incorporating a group of differential equations that quantify the emergent properties of a system.

HIV treatment as prevention and HPTN 052

PURPOSE OF REVIEW

This review summarizes the development and implementation of a large clinical trial, HIV Prevention Trials Network (HPTN) 052, whose initial results were recently presented and published.

RECENT FINDINGS

A randomized, clinical trial demonstrated that antiretroviral therapy reduces the sexual transmission of HIV in HIV-serodiscordant couples by more than 96%. The logistical challenges in preparing for and conducting such a trial were considerable.

SUMMARY

HPTN 052 required many years of preparation, considerable collaboration between National Institute of Health and six pharmaceutical companies, and careful ongoing consideration of a large number of ethical issues. HPTN 052 revealed the magnitude of benefit when using antiretroviral therapy to prevent the transmission of HIV, and served as proof of a concept. The results have proven central to the development of new global HIV-prevention efforts.

HIV treatment as prevention: debate and commentary--will early infection compromise treatment-as-prevention strategies?

Universal HIV testing and immediate antiretroviral therapy for infected individuals has been proposed as a way of reducing the transmission of HIV and thereby bringing the HIV epidemic under control. It is unclear whether transmission during early HIV infection--before individuals are likely to have been diagnosed with HIV and started on antiretroviral therapy--will compromise the effectiveness of treatment as prevention. This article presents two opposing viewpoints by Powers, Miller, and Cohen, and Williams and Dye, followed by a commentary by Fraser.

Perceived acceptability of home-based couples voluntary HIV counseling and testing in Northern Tanzania

It is estimated that 5.6% of the Tanzanian population ages 15-49 are infected with HIV, but only 30% of adults have ever had an HIV test. Couples' testing has proven to increase testing coverage and introduce HIV prevention, but barriers include access to testing services and unequal gender dynamics in relationships. Innovative approaches are needed to address barriers to couple's testing and increase uptake of HIV testing. Using qualitative data collection methods, a formative study was conducted to assess the acceptability of a home-based couples counseling and testing (HBCCT) approach. Eligible study participants included married men and women, HIV-infected individuals, health care and home-based care providers, voluntary counseling and testing counselors, and community leaders. A total of 91 individuals participated in focus group discussions (FGDs) and in-depth interviews conducted between September 2009 and January 2010 in rural settings in Northern Tanzania. An HBCCT intervention appears to be broadly acceptable among participants. Benefits of HBCCT were identified in terms of access, confidentiality, and strengthening the relationship. Fears of negative consequences from knowing one's HIV status, including stigma, blame, physical abuse, or divorce, remain a concern and a potential barrier to the successful provision of the intervention. Lessons for implementation highlighted the importance of appointments for home visits, building relationships of confidence and trust between counselors and clients, and assessing and responding to a couple's readiness to undergo HIV testing. HBCCT should addresses HIV stigma, emphasize confidentiality, and improve communication skills for disclosure and decision-making among couples.

Prevention of HIV-1 infection with early antiretroviral therapy

BACKGROUND

Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples.

METHODS

In nine countries, we enrolled 1763 couples in which one partner was HIV-1-positive and the other was HIV-1-negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1-infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1-related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1-negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death.

RESULTS

As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P=0.01).

CONCLUSIONS

The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 052 ClinicalTrials.gov number, NCT00074581.).

HIV prevention transformed: the new prevention research agenda

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