A Global Meta-analysis of the Prevalence of HIV, Hepatitis C Virus, and Hepatitis B Virus Among People Who Inject Drugs-Do Gender-Based Differences Vary by Country-Level Indicators?

Sex and gender differences in hepatitis C virus risk, prevention, and cascade of care in people who inject drugs: systematic review and meta-analysis

Background

People who inject drugs (PWID) are a priority population in HCV elimination programming. Overcoming sex and gender disparities in HCV risk, prevention, and the cascade of care is likely to be important to achieving this goal, but these have not yet been comprehensively reviewed.

Methods

Systematic review and meta-analysis. We searched Pubmed, EMBASE and the Cochrane Database of Systematic Reviews 1 January 2012-22 January 2024 for studies of any design reporting sex or gender differences among PWID in at least one of: sharing of needles and/or syringes, incarceration history, injection while incarcerated, participation in opioid agonist treatment or needle and syringe programs, HCV testing, spontaneous HCV clearance, direct-acting antiviral (DAA) treatment initiation or completion, and sustained virological response (SVR). Assessment of study quality was based on selected aspects of study design. Additional data were requested from study authors. Data were extracted in duplicate and meta-analysed using random effects models. PROSPERO registration CRD42022342806.

Findings

9533 studies were identified and 92 studies were included. Compared to men, women were at greater risk for receptive needle and syringe sharing (past 6-12 months: risk ratio (RR) 1.12; 95% confidence interval (CI) 1.01-1.23; <6 months: RR 1.38; 95% CI 1.09-1.76), less likely to be incarcerated (lifetime RR 0.64; 95% CI 0.57-0.73) more likely to be tested for HCV infection (lifetime RR 1.07; 95% CI 1.01, 1.14), more likely to spontaneously clear infection (RR1.58; 95% CI 1.40-1.79), less likely to initiate DAA treatment (0.84; 95% CI 0.78-0.90), and more likely to attain SVR after completing DAA treatment (RR 1.02; 95% CI 1.01-1.04).

Interpretation

There are important differences in HCV risk and cascade of care indicators among people who inject drugs that may impact the effectiveness of prevention and treatment programming. Developing and assessing the effectiveness of gender-specific and gender-responsive HCV interventions should be a priority in elimination programming.

Funding

Réseau SIDA-MI du Québec.

All-cause mortality before and after DAA availability among people living with HIV and HCV: An international comparison between 2010 and 2019

BACKGROUND

Among people living with HIV and hepatitis C virus (HCV), people who inject drugs (PWID) have historically experienced higher mortality rates. Direct-acting antivirals (DAA), which have led to a 90 % HCV cure rate independently of HIV co-infection, have improved mortality rates. However, DAA era mortality trends among PWID with HIV/HCV remain unknown. Using data from the International Collaboration on Hepatitis C Elimination in HIV Cohorts (InCHEHC), we compared pre/post-DAA availability mortality changes in three groups: PWID, men who have sex with men (MSM), and all other participants.

METHODS

We included InCHEHC participants with HIV/HCV followed between 2010 and 2019 in Canada, France, the Netherlands, Spain, and Switzerland. All-cause mortality hazard was compared in the three groups, using Cox proportional hazards regression models adjusted for sex, age, advanced fibrosis/cirrhosis, and pre/post DAA availability.

RESULTS

Of the 11,029 participants, 76 % were men, 46 % were PWID, baseline median age was 46 years (interquartile range [IQR] = 40;51), and median CD4 T-cell count was 490 cells/mm3 (IQR = 327;689). Over the study period (median follow-up = 7.2 years (IQR = 3.7;10.0)), 6143 (56 %) participants received HCV treatment, 4880 (44 %) were cured, and 1322 participants died (mortality rate = 1.81/100 person-years (PY) [95 % confidence interval (CI)=1.72-1.91]). Overall, PWID had higher mortality rates than MSM (2.5/100 PY [95 % CI = 2.3-2.6] vs. 0.8/100 PY [95 % CI = 0.7-0.9], respectively). Unlike women with other transmission modes, those who injected drugs had a higher mortality hazard than men who did not inject drugs and men who were not MSM (adjusted Hazard-Ratio (aHR) [95 % CI] = 1.3[1.0-1.6]). Post-DAA availability, mortality decreased among MSM in the Netherlands, Spain, and Switzerland and increased among PWID in Canada (aHR [95 % CI] = 1.73 [1.15-2.61]).

CONCLUSION

Post-DAA availability, all-cause mortality did not decrease in PWID. Determinants of cause-specific deaths (drug-related, HIV-related, or HCV-related) need to be identified to explain persistently high mortality among PWID in the DAA era.

Effects of a social network intervention on HIV seroconversion among people who inject drugs in Ukraine: moderation by network gender composition

BACKGROUND

Women who inject drugs in Ukraine are disproportionately burdened by HIV. To help address the needs of this population, a greater understanding of how interventions may uniquely benefit women who inject drugs is needed.

METHODS

Data come from a randomized controlled trial of a social network intervention targeting people who inject drugs in Ukraine (N = 1195). Indexes, plus two of their injection network members, received HIV testing and counseling (control arm) or HIV testing and counseling plus a social network intervention (intervention arm), in which indexes were trained to influence network members' risk behaviors. We used Cox regressions with interaction terms to assess differences in time to HIV seroconversion between arms by network gender composition and gender of the index. For significant interaction terms, we calculated simple effects, generated survival functions using Kaplan-Meier methods, and compared survival curves using log-rank tests.

RESULTS

At 12 months, there were 45 seroconversions among women (40.0 [28.3, 51.7] per 100 person years) and 111 among men (28.4 [23.1, 33.6] per 100 person years) in the control arm; there were 27 seroconversions among women (17.1 [10.7, 23.6] per 100 person years) and 77 among men (18.7 [14.5, 22.9] per 100 person years) in the intervention arm. Network gender composition (but not gender of the index) moderated the intervention effect on HIV incidence (p < 0.05). Specifically, the intervention appeared to be even more protective against HIV acquisition as female gender composition increased. In the intervention arm, the HIV seroconversion hazard rate was 44% lower with 1 network female; 61% lower with 2 network females; and 72% lower with 3 network females.

CONCLUSIONS

A greater number of women in an injection network, coupled with the provision of risk-reduction strategies, is associated with HIV risk-mitigation, though the mechanisms through which this occurs remain unclear. Findings can support new research and practice directions that prioritize women who inject drugs and more thoughtfully support their health and wellbeing.

Social Networks, Stigma, and Hepatitis C Care Among Women Who Inject Drugs: Findings from A Community Recruited Sample

This study explores the role of perceived HCV stigma and social networks on HCV care among people who inject drugs (PWID) of both sexes, and solely among women who inject drugs (WWID). Data were from 269 HCV positive PWID, community-recruited through street-based outreach in Baltimore, MD. We defined HCV stigma based on participants' perceptions of treatment by others and their need to conceal their HCV status. Among WWID, HCV stigma was linked with decreased odds of undergoing liver disease staging (aOR = 0.33, 95% CI: 0.13,0.85) or to have attempted to get the HCV cure (aOR = 0.39, CI: 0.16,0.97), these associations were not evident in the overall sample with both sexes. Social network characteristics were significant correlates of HCV care in the overall sample, and these associations were stronger among WWID. WWID with more HCV positive social network members had higher odds of an HCV-related healthcare visit in the prior 12 months (aOR = 4.28, CI: 1.29,14.17) and to have undergone liver disease staging (aOR = 2.85, CI: 1.01,8.05). WWID with more social network members aware of the HCV cure were more likely to report an attempt at obtaining the HCV cure (aOR = 5.25, CI: 1.85,14.89). Our results suggest complexity in the role of social networks and stigma on HCV care.

Prevalence of injecting drug use and HIV, hepatitis B, and hepatitis C in people who inject drugs in the Eastern Mediterranean region: a systematic review and meta-analysis

BACKGROUND

Considerable disease burden is attributed to injecting drug use (IDU). This regional systematic review and meta-analysis aimed to assess the prevalence of IDU and the characteristics of people who inject drugs in the 22 countries of the WHO Eastern Mediterranean region.

METHODS

We conducted a systematic review and meta-analysis on the prevalence of IDU, estimation of the population size of people who inject drugs, the characteristics of people who inject drugs, commonly injected drugs, the prevalence of HIV, hepatitis C virus, and hepatitis B virus in people who inject drugs, and opioid agonist treatment and needle and syringe programme services. We searched PubMed, Web of Science, Scopus, Embase, and the Index Medicus for the Eastern Mediterranean Region for documents published between Jan 1, 2010, and April 17, 2022, with no language restrictions. We also searched government reports, civil society information, and UN websites and databases for grey literature published between Jan 1, 2010, and April 17, 2022. Documents were eligible if they reported or estimated an indicator of interest, or reported enough data to permit calculation of the indicator. We extracted data from the eligible documents and calculated national and regional estimates.

FINDINGS

We identified 38 283 documents and included 201 documents in the systematic review. A total of 115 documents were included for the four outcomes for which meta-analyses were performed. The number of people who inject drugs was estimated as 864 597 (95% CI 641 909-1 205 255), amounting to a prevalence of 20·0 per 10 000 adults (95% CI 14·9-27·9) in the region. Among people who inject drugs, the prevalence of HIV was estimated as 19·22% (95% CI 12·86-26·36), hepatitis C virus as 44·82% (29·32-61·16), and hepatitis B virus as 2·66% (0·84-7·26). Countries varied greatly regarding the variables of interest and the availability of relevant data. Nine countries provided needle and syringe programme services and seven countries provided opioid agonist treatment services, mostly with very low, low, or unclear coverage.

INTERPRETATION

The prevalence of IDU in the Eastern Mediterranean region is lower than the global mean, particularly among women. The HIV infection rate is higher than the global mean, and the hepatitis C virus infection rate is lower than the global mean. Harm-reduction services are underdeveloped. Data collection on IDU and provision of services need improvement in the region.

FUNDING

World Health Organization.

TRANSLATIONS

For the Arabic, Farsi and French translations of the abstract see Supplementary Materials section.

Gender Differences in the Pathogenesis and Risk Factors of Hepatocellular Carcinoma

Several chronic liver diseases are characterized by a clear gender disparity. Among them, hepatocellular carcinoma (HCC) shows significantly higher incidence rates in men than in women. The different epidemiological distribution of risk factors for liver disease and HCC only partially accounts for these gender differences. In fact, the liver is an organ with recognized sexual dysmorphism and is extremely sensitive to the action of androgens and estrogens. Sex hormones act by modulating the risk of developing HCC and influencing its aggressiveness, response to treatments, and prognosis. Furthermore, androgens and estrogens are able to modulate the action of other factors and cofactors of liver damage (e.g., chronic HBV infection, obesity), significantly influencing their carcinogenic power. The purpose of this review is to examine the factors related to the different gender distribution in the incidence of HCC as well as the pathophysiological mechanisms involved, with particular reference to the central role played by sex hormones.

Incidence of HIV and hepatitis C virus among people who inject drugs, and associations with age and sex or gender: a global systematic review and meta-analysis

BACKGROUND

Measuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender.

METHODS

In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle-Ottawa scale. This study is registered with PROSPERO, CRD42020220884.

FINDINGS

Our updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987-2021 for HIV and 1992-2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3-2·3; I2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0-14·6; I2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2-1·8; I2=66·9%) and HCV (1·5, 1·3-1·8; I2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1-1·6; I2=55·3%) and HCV (1·2, 1·1-1·3; I2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6-7), indicating moderate risk.

INTERPRETATION

Although sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs.

FUNDING

Canadian Institutes of Health Research, Fonds de recherche du Québec-Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO.

HCV, HIV AND HBV rapid test diagnosis in non-clinical outreach settings can be as accurate as conventional laboratory tests

Point of care rapid diagnostic tests (POC-RDT) for Hepatitis C virus (HCV), Human Immunodeficiency virus (HIV) and Hepatitis B virus (HBV), are ideal for screening in non-clinical outreach settings as they can provide immediate results and facilitate diagnosis, allowing high risk population screening. The aim of this study was to compare POC-RDT with laboratory conventional tests. A total of 301 vulnerable evaluable subjects (drug users, migrants and homeless population) were recruited at a mobile screening unit in outreach settings in Madrid. Fingerprick whole blood capillary samples were tested using the SD BIOLINE HCV POC-RDT, Determine HIV Early Detect and Determine HBsAg 2, and the results were assessed against the LIAISON XL HCV, HIV and Murex-HBsAg-Quant, reference assays, respectively. The feasibility and user satisfaction of the POC-RDT were evaluated through a questionnaire. The resolved sensitivity and resolved specificity and their 95% confidence intervals (95% CI) were as follows, respectively: SD-BIOLINE-HCV: 98.8% (95% CI 93.4, 100.0) and 100.0% (95% CI 98.3, 100.0); Determine HIV Early Detect: 100% (95% CI 85.2, 100.0) and 100% (95% CI 98.7, 100); and Determine HBsAg 2: 66.7% (95% CI 9.4, 99.2) and 100.0% (95% CI 98.7, 100.0). As expected, the number of subjects with a confirmed positive result for HBsAg was very low (n = 4). Therefore, the analytical sensitivity has been evaluated in addition: The Determine HBsAg 2 test demonstrated 100% sensitivity for standard concentrations ≥ 0.125 IU/mL. The subject questionnaire yielded positive feedback for most subjects. The POC-RDT fingerprick blood collection method was well received, and the tests demonstrated a comparable clinical performance with conventional tests in outreach settings and vulnerable high-risk populations.

Health inequalities in infectious diseases: a systematic overview of reviews

OBJECTIVES

The aim of this systematic overview of reviews was to synthesise available evidence on inequalities in infectious disease based on three dimensions of inequalities; inclusion health groups, protected characteristics and socioeconomic inequalities.

METHODS

We searched MEDLINE, Embase, Web of Science and OpenGrey databases in November 2021. We included reviews published from the year 2000 which examined inequalities in the incidence, prevalence or consequences of infectious diseases based on the dimensions of interest. Our search focused on tuberculosis, HIV, sexually transmitted infections, hepatitis C, vaccination and antimicrobial resistance. However, we also included eligible reviews of any other infectious diseases. We appraised the quality of reviews using the Assessment of Multiple Systematic Reviews V.2 (AMSTAR2) checklist. We conducted a narrative data synthesis.

RESULTS

We included 108 reviews in our synthesis covering all the dimensions of inequalities for most of the infectious disease topics of interest, however the quality and volume of review evidence and consistency of their findings varied. The existing literature reviews provide strong evidence that people in inclusion health groups and lower socioeconomic status are consistently at higher risk of infectious diseases, antimicrobial resistance and incomplete/delayed vaccination. In the protected characteristics dimension, ethnicity, and sexual orientation are important factors contributing to inequalities across the various infectious disease topics included in this overview of reviews.

CONCLUSION

We identified many reviews that provide evidence of various types of health inequalities in different infectious diseases, vaccination, and antimicrobial resistance. We also highlight areas where reviews may be lacking. The commonalities in the associations and their directions suggest it might be worth targeting interventions for some high risk-groups that may have benefits across multiple infectious disease outcomes rather than operating purely in infectious disease siloes.

HCV Genotype Distribution Among People Who Inject Drug in Turkey: Findings from Multicenter and Cross-Sectional Study

Background

Hepatitis C virus (HCV) infection is very common in people who inject drugs (PWID). Studies about the prevalence and genotype distribution of the HCV among PWID are very crucial for developing strategies to manage HCV infection. This study's objective is to map the distribution of HCV genotypes among PWID from various regions of Turkey.

Method

This prospective, multicenter, cross-sectional study involved 197 PWID who tested positive for anti-HCV antibodies from 4 different addiction treatment facilities in Turkey. Interviews were done with people who had anti-HCV antibodies, and blood samples were taken to check the HCV RNA viremia load and genotyping.

Results

This study was conducted on 197 individuals with a mean age of 30.3 ± 8.6 years. 9.1% (136/197 patients) had a detectable HCV-RNA viral load. Genotype 3 was the most commonly observed genotype by 44.1%, followed by genotype 1a by 41.9%, genotype 2 by 5.1%, genotype 4 by 4.4%, and genotype 1b by 4.4%. Whereas genotype 3 was dominant with 44.4% at the central Anatolia region of Turkey, the frequencies of genotypes 1a and 3, which were predominantly detected in the south and northwest regions of Turkey, were very close to each other.

Conclusion

Although genotype 3 is the predominant genotype in the PWID population in Turkey, the prevalence of HCV genotype varied across the country. To eliminate HCV infection in the PWID, treatment and screening strategies that differ by genotype are essentially required. Especially identification of genotypes will be useful in developing individualized treatments and determining national prevention strategies.

Temporal Trend and Clinical Outcomes in HIV and Non-HIV Patients following Liposuction: A Propensity-Matched Analysis

BACKGROUND

Because of the availability of highly active antiretroviral therapy, individuals infected with human immunodeficiency virus (HIV) are enjoying greater longevity with chronic conditions including abnormal adipose distribution. However, prior data on postoperative outcomes of liposuction in HIV-positive patients were limited by small sample size. Therefore, the authors aimed to compare differences in temporary trend, clinical characteristics, and outcomes between patients with and without HIV who underwent liposuction.

METHODS

The National Inpatient Sample database from 2010 to 2017 was queried to identify patients who underwent liposuction. Univariate, multivariate logistic regression and 1:4 propensity score-matched analyses were used to assess the primary outcomes (i.e., in-hospital mortality and postoperative outcomes) and secondary outcomes (i.e., discharge disposition, prolonged length of stay, and total cost).

RESULTS

Overall, 19,936 patients who underwent liposuction were identified, among whom 61 patients (0.31%) were infected with HIV. Patients with HIV were more likely to be male, insured by Medicare, and had more comorbidities and lower income. Unadjusted length of stay was longer among patients with HIV (OR, 1.81; 95% CI, 1.09 to 2.99; P = 0.020); nevertheless, multivariable models and propensity score-matched analysis demonstrated that patients with HIV were no more likely to have complications than the general population. This was also the case for length of stay and total costs.

CONCLUSIONS

The authors' findings indicated that patients with HIV who underwent liposuction did not experience an increased risk of major complication or mortality. Liposuction could be safely considered as a surgical treatment for HIV-positive patients with local fat deposition.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Dopamine, Immunity, and Disease

The neurotransmitter dopamine is a key factor in central nervous system (CNS) function, regulating many processes including reward, movement, and cognition. Dopamine also regulates critical functions in peripheral organs, such as blood pressure, renal activity, and intestinal motility. Beyond these functions, a growing body of evidence indicates that dopamine is an important immunoregulatory factor. Most types of immune cells express dopamine receptors and other dopaminergic proteins, and many immune cells take up, produce, store, and/or release dopamine, suggesting that dopaminergic immunomodulation is important for immune function. Targeting these pathways could be a promising avenue for the treatment of inflammation and disease, but despite increasing research in this area, data on the specific effects of dopamine on many immune cells and disease processes remain inconsistent and poorly understood. Therefore, this review integrates the current knowledge of the role of dopamine in immune cell function and inflammatory signaling across systems. We also discuss the current understanding of dopaminergic regulation of immune signaling in the CNS and peripheral tissues, highlighting the role of dopaminergic immunomodulation in diseases such as Parkinson's disease, several neuropsychiatric conditions, neurologic human immunodeficiency virus, inflammatory bowel disease, rheumatoid arthritis, and others. Careful consideration is given to the influence of experimental design on results, and we note a number of areas in need of further research. Overall, this review integrates our knowledge of dopaminergic immunology at the cellular, tissue, and disease level and prompts the development of therapeutics and strategies targeted toward ameliorating disease through dopaminergic regulation of immunity. SIGNIFICANCE STATEMENT: Canonically, dopamine is recognized as a neurotransmitter involved in the regulation of movement, cognition, and reward. However, dopamine also acts as an immune modulator in the central nervous system and periphery. This review comprehensively assesses the current knowledge of dopaminergic immunomodulation and the role of dopamine in disease pathogenesis at the cellular and tissue level. This will provide broad access to this information across fields, identify areas in need of further investigation, and drive the development of dopaminergic therapeutic strategies.

Applications of research evidence during processes to acquire approvals for syringe services program implementation in rural counties in Kentucky

INTRODUCTION

Despite decades of empirical research in the US and internationally documenting the benefits of implementing syringe services programs (SSPs), their implementation may be controversial in many jurisdictions. Better understanding how research evidence is applied during SSP implementation processes may enable the public health workforce to advocate for program scale up. This study explores applications of research evidence during processes to acquire approvals for SSP implementation in rural counties in Kentucky.

METHODS

In-depth interviews were conducted among eighteen stakeholders (e.g. health department directors, SSP operators) involved in SSP implementation in rural Kentucky counties. Stakeholders were asked to describe the contexts surrounding SSP implementation processes. Interviews were transcribed and analysed for applications of research evidence. Research evidence-related quotes were subsequently categorised based on the typologies for applications of research evidence developed by Weiss et al. (instrumental, conceptual, and symbolic) and a fourth category for instances when research evidence was not used.

RESULTS

Instrumental applications of research evidence occurred at the intrapersonal and interpersonal levels to dispel concerns about SSPs and formed the basis for implementation support. SSP proponents used research evidence in a conceptual manner to address underlying attitudes and beliefs that were not evidence-based. Participants reported symbolic research evidence applications to justify pre-existing attitudes and beliefs about meeting the public health needs of people who inject drugs. Lastly, in some instances, research evidence was met with scepticism and an unwillingness to consider its merits.

CONCLUSION

Applications of research evidence during SSP implementation approval processes in rural Kentucky counties were heterogeneous in nature. Better understanding the diversity of ways in which research evidence may be employed during SSP implementation processes may support efforts to improve the public health of people who inject drugs.Key messagesApplications of research evidence during SSP implementation approval processes in rural Kentucky counties were heterogeneous in nature.Instrumental applications of research evidence occurred at the intrapersonal and interpersonal levels to dispel concerns about SSPs and formed the basis for implementation support.SSP proponents used research evidence in a conceptual manner to address underlying attitudes and beliefs that were not evidence-based.

Characteristics associated with HIV and hepatitis C seroprevalence among sexual and injecting partners of HIV positive persons who inject drugs in Nairobi and coastal Kenya

Background

Persons who inject drugs (PWID) have higher HIV and hepatitis C virus (HCV) seroprevalence than the general population in many parts of sub-Saharan Africa (SSA). The seroprevalences of HIV and HCV are also higher in coastal Kenya than in Nairobi. Understanding drivers of regional HIV and HCV variation among PWID in Kenya may inform population-specific prevention interventions.

Methods

Using a cross-sectional study, we defined HIV and HCV seroprevalence among persons identified as sexual or injecting partners of HIV positive PWID in two regions of Kenya and used logistic regression to identify demographic and behavioral characteristics associated with higher seroprevalence.

Results

Among 2386 partners, 469 (19.7%) tested HIV positive and 297(12.4%) tested HCV antibody positive. Partners on the Coast were more likely to live with HIV (seroprevalences: Coast = 23.8%, Nairobi = 17.1%; p < 0.001) and be HCV antibody positive (seroprevalences: Coast = 17.0%, Nairobi = 8.6%; p < 0.001). After adjusting for sex, age, and years injecting and accounting for clustering by site, the higher prevalence of both diseases in the Coast remained significant for HIV (OR 1.68, 95% CI 1.13–2.51) but not for HCV (OR 1.72, 95% CI 0.84–3.74). Compared to those recruited in Nairobi, partners on the Coast were older (Coast = 35 years, Nairobi = 31 years; p < 0.001), more likely to be male (Coast = 77.6%, Nairobi = 61.7%; p < 0.001), to have paid (Coast = 59.2%, Nairobi = 32.8%; p < 0.001) or received (Coast = 44.2%, Nairobi 35.4%; p < 0.001) money for sex, or to have had sex with someone they knew to be HIV positive (Coast 22.0%, Nairobi 10.8%; p < 0.001). Partners who had injected for five or more years had 1.48 times greater odds (95% CI 1.20–1.82) of living with HIV compared to partners who injected less than 5 years and more than twice the odds of HCV (95% CI 1.84–4.11).

Conclusion

HIV and HCV seroprevalence among sexual and injecting partners of PWID was, respectively, 5 times and > 12 times greater than is reported among the general population in Kenya (4% and < 1%, respectively). Providing resources and education will be crucial to reduce exposure and to maintain the lower needle and equipment sharing that we observed compared to other studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07036-8.

Participants of a mail delivery syringe services program are underserved by other safe sources for sterile injection supplies

BACKGROUND

In the United States, accessing sterile injection supplies remains challenging for many people who inject drugs (PWID). Although women are less likely to inject drugs than men, women who do inject are disproportionately affected by IDU-related complications. Needle Exchange Technology (NEXT), the first formal online accessed mail delivery syringe services program (SSP) in the US, may overcome access barriers. We evaluated whether NEXT was reaching women participants and people without access to other safe sources of sterile injection supplies.

METHODS

This cross-sectional study examined NEXT participants who enrolled in the mail-delivery SSP from February 2018 through March 2021. All NEXT participants completed an online questionnaire during enrollment, which included sociodemographic and clinical characteristics and injection-related risk factors (including prior sources of sterile injection supplies). Multivariable logistic regression (MVR) was used to examine associations between gender and prior use of safe sources of injection supplies (i.e., SSPs or pharmacies).

RESULTS

1,032 participants received injection supplies. Median age was 34 and participants were mostly cis-gendered women (55%) and white (93%). 34% reported infection with HCV; women were more likely to report HCV infection than men (38% vs 28%; p < 0.01). 68% of participants acquired injection supplies from less safe sources. Few participants exclusively used safe sources for injection supplies (26%). In adjusted MVR analysis, women participants had significantly lower odds than men of having exclusively used safe sources for injection supplies (adjusted OR 0.71, 95% CI 0.52, 0.98).

CONCLUSION

Our findings suggest that NEXT services are utilized by women and people without prior access to sterile injection supplies. Women participants were less likely than men to have exclusively used safe sources for sterile injection supplies. Future research should explore women's preference for mail-delivery over in-person SSPs and determine whether online accessed mail delivery services can reach other underserved populations of PWID.

Co-receptor signaling in the pathogenesis of neuroHIV

The HIV co-receptors, CCR5 and CXCR4, are necessary for HIV entry into target cells, interacting with the HIV envelope protein, gp120, to initiate several signaling cascades thought to be important to the entry process. Co-receptor signaling may also promote the development of neuroHIV by contributing to both persistent neuroinflammation and indirect neurotoxicity. But despite the critical importance of CXCR4 and CCR5 signaling to HIV pathogenesis, there is only one therapeutic (the CCR5 inhibitor Maraviroc) that targets these receptors. Moreover, our understanding of co-receptor signaling in the specific context of neuroHIV is relatively poor. Research into co-receptor signaling has largely stalled in the past decade, possibly owing to the complexity of the signaling cascades and functions mediated by these receptors. Examining the many signaling pathways triggered by co-receptor activation has been challenging due to the lack of specific molecular tools targeting many of the proteins involved in these pathways and the wide array of model systems used across these experiments. Studies examining the impact of co-receptor signaling on HIV neuropathogenesis often show activation of multiple overlapping pathways by similar stimuli, leading to contradictory data on the effects of co-receptor activation. To address this, we will broadly review HIV infection and neuropathogenesis, examine different co-receptor mediated signaling pathways and functions, then discuss the HIV mediated signaling and the differences between activation induced by HIV and cognate ligands. We will assess the specific effects of co-receptor activation on neuropathogenesis, focusing on neuroinflammation. We will also explore how the use of substances of abuse, which are highly prevalent in people living with HIV, can exacerbate the neuropathogenic effects of co-receptor signaling. Finally, we will discuss the current state of therapeutics targeting co-receptors, highlighting challenges the field has faced and areas in which research into co-receptor signaling would yield the most therapeutic benefit in the context of HIV infection. This discussion will provide a comprehensive overview of what is known and what remains to be explored in regard to co-receptor signaling and HIV infection, and will emphasize the potential value of HIV co-receptors as a target for future therapeutic development.

Seroprevalence of hepatitis B virus infection, anti-HCV antibodies and HIV and knowledge among people who use drugs attending methadone therapy clinic in Tanzania; a cross-sectional study

Background

Methadone therapy clinics have been recently introduced in Tanzania, aiming at reducing risk behaviors and infection rates of viral hepatitis and HIV among people who use drugs. The objective of this study was to estimate the prevalence, associated factors and knowledge level of these conditions among people who use drugs attending a methadone clinic in Tanzania.

Methods

We enrolled 253 People who using drugs receiving Methadone therapy. Clinical data was retrospectively collected from the medical records and face-to face interviews were conducted to determine the behavioral risk factors and respondents’ knowledge on viral hepatitis and HIV.

Results

An overall seroprevalence of viral hepatitis (either hepatitis B surface antigen or anti-hepatitis C virus) was 6.3%, while that of hepatitis B virus mono infection was 3.5% and anti-hepatitis C antibodies was 3.5%. Seroprevalence of HIV was 12.6%. Viral hepatitis was strongly predicted by advanced age (> 35 years) (p = 0.02) and staying at Kirumba area (p = 0.004), and HIV infection was predicted by increased age (> 37 years) (p = 0.04) and female sex (p < 0.001). Regarding the knowledge of viral hepatitis, majority of the respondents were unaware of the transmission methods and availability of hepatitis B virus vaccines and only 17% were classified as well informed (provided ≥4 correct answers out of 7 questions). Good knowledge was highly predicted by higher education level of the individual (p = 0.001).

Conclusions

Despite the efforts to curb viral hepatitis and HIV infections through Methadone clinics, infection rates among people who use drugs are still high and the general knowledge on preventive measures is inadequate.

Association between opioid agonist therapy use and HIV testing uptake among people who have recently injected drugs: a systematic review and meta-analysis

BACKGROUND AND AIM

Globally, nearly one in five people who inject drugs (PWID) are living with HIV, and the rate of new HIV infections in PWID is increasing in some settings. Early diagnosis is crucial for effective HIV control. We reviewed the evidence on the association between opioid agonist therapy (OAT) and HIV testing uptake among PWID.

METHODS

We conducted a systematic review searching MEDLINE, Scopus, Web of Science, Cochrane Central Register of Controlled Trials and PsycINFO for studies published from January 2000 to March 2019. Reference lists and conference proceedings were hand-searched. Observational and intervention studies were eligible for inclusion. Risk of bias was assessed using the Risk of Bias in Non-Randomised Studies of Interventions (ROBINS-I) tool. Meta-analyses were conducted using random-effects models.

RESULTS

Of 13 373 records identified, 11 studies from Australia, Europe, Malaysia and the United States were included. All studies had at least a serious risk of bias, largely due to confounding and selection bias, making it difficult to draw causal conclusions from the evidence. Ten studies provided data on the association between current OAT use and recent HIV testing. Six showed a positive association, while four provided little evidence of an association: pooled odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.28-2.27. Looking at having ever been on OAT and having ever been HIV tested, seven studies showed a positive association and three showed either weak or no evidence of an association: pooled OR = 3.82, 95% CI = 2.96-4.95.

CONCLUSIONS

Opioid agonist therapy may increase uptake of HIV testing among people who inject drugs, providing further evidence that opioid agonist therapy improves the HIV treatment care cascade.

Dopamine Levels Induced by Substance Abuse Alter Efficacy of Maraviroc and Expression of CCR5 Conformations on Myeloid Cells: Implications for NeuroHIV

Despite widespread use of antiretroviral therapy (ART), HIV remains a major public health issue. Even with effective ART many infected individuals still suffer from the constellation of neurological symptoms now known as neuroHIV. These symptoms can be exacerbated by substance abuse, a common comorbidity among HIV-infected individuals. The mechanism(s) by which different types of drugs impact neuroHIV remains unclear, but all drugs of abuse increase central nervous system (CNS) dopamine and elevated dopamine increases HIV infection and inflammation in human myeloid cells including macrophages and microglia, the primary targets for HIV in the brain. Thus, drug-induced increases in CNS dopamine may be a common mechanism by which distinct addictive substances alter neuroHIV. Myeloid cells are generally infected by HIV strains that use the chemokine receptor CCR5 as a co-receptor, and our data indicate that in a subset of individuals, drug-induced levels of dopamine could interfere with the effectiveness of the CCR5 inhibitor Maraviroc. CCR5 can adopt distinct conformations that differentially regulate the efficiency of HIV entry and subsequent replication and using qPCR, flow cytometry, Western blotting and high content fluorescent imaging, we show that dopamine alters the expression of specific CCR5 conformations of CCR5 on the surface of human macrophages. These changes are not affected by association with lipid rafts, but do correlate with dopamine receptor gene expression levels, specifically higher levels of D1-like dopamine receptors. These data also demonstrate that dopamine increases HIV replication and alters CCR5 conformations in human microglia similarly to macrophages. These data support the importance of dopamine in the development of neuroHIV and indicate that dopamine signaling pathways should be examined as a target in antiretroviral therapies specifically tailored to HIV-infected drug abusers. Further, these studies show the potential immunomodulatory role of dopamine, suggesting changes in this neurotransmitter may also affect the progression of other diseases.

Gender Equity and Vertically Transmitted Infections: A Country-Level Analysis Across 153 Countries

Purpose: Gender inequality is a barrier to education toward women and accessibility to health facilities, which are important for preventing vertical transmission. This study was conducted to analyze the impact of gender equity on vertically transmitted infections (hepatitis viruses, human immunodeficiency virus [HIV], and syphilis) using country-level indicators.

Methods: The relationship between the Global Gender Gap Index (GGGI), which is indicator of gender equity, and vertical transmission was analyzed. GGGI scores were collected from 153 countries in 2020. Vertical transmission included 10 outcomes for hepatitis viruses, HIV, and syphilis. Generalized linear model (GLM) was used for analyzing the relationship. Other predictors included skilled birth attendant and country income.

Results: The median GGGI score was 0.706 (interquartile range, 0.664–0.736). GLM showed that the GGGI score was significantly associated with the incidence of both chronic hepatitis B and C in under 5 years (both p<0.001). For HIV, GGGI score was significantly associated with the pregnant women with unknown HIV status (p=0.001), no early infant diagnosis (p=0.027), and final transmission rate (p=0.005). There was no significant predictor for pregnant women who have not received antiretroviral therapy for prevention of mother-to-child transmission. All syphilis indicators have improved in high-income countries compared to low-income countries. GGGI score had a significant association only with no syphilis screening (p<0.001).

Conclusions: A lower GGGI score was associated with higher vertical transmission of hepatitis and HIV. The improvement of gender equity might prevent vertical transmission of these viruses. Further intervention studies are warranted to verify the results.

A prospective cohort study of risk behaviours, retention and loss to follow-up over 5 years among women and men in a needle exchange program in Stockholm, Sweden

BACKGROUND

Needle exchange programs (NEP) are important in reducing risk behaviours among people who inject drugs (PWID), also exposed to HIV and hepatitis C (HCV) through injecting drug use (IDU). Women (WWID) compared to men who inject drugs (MWID), are particularly vulnerable with complex needs, however less is known about their risk determinants and NEP outcomes.

METHODS

In an open prospective NEP cohort, 697 WWID and 2122 MWID were followed, 2013-2018. Self-reported socio/drug-related determinants for receptive injection (needle/syringe and paraphernalia) and sexual risk behaviours at enrolment, lost to follow-up (LTFU) and probability of retention, were assessed for both groups. Multivariable logistic regression (adjusted odds ratios, aOR) for enrolment and Poisson regression (adjusted incidence rate ratios, aIRR) for LTFU, were used. Cumulative NEP-retention probability was analysed using a six- and 12-month scenario.

RESULTS

At NEP enrolment, injection risk behaviours among WWID were associated with: younger age; homelessness; amphetamine-IDU; non-participation in opioid substitution therapy (OST); history of custody and among MWID: lower education level; cohabitation; homelessness, being a tenant; amphetamine-IDU; non-participation in OST; history of being sectioned, HIV-negative and HCV-positive. Condomless sex among WWID was associated with: younger age; lower education-level; cohabitation; having a partner; amphetamine-IDU; non-participation in OST; being HIV-negative and HCV-positive and among MWID: younger age; married; cohabitation; having a partner; amphetamine-IDU; non-participation in OST; history of custody, prison and being HIV-negative. WWID had higher NEP-retention levels compared to MWID over time. Being LTFU among WWID was associated with being HIV-negative and reporting injection risk behaviours and among MWID, younger age, non-participation in OST, being HIV-negative and having protected sex.

CONCLUSIONS

Despite better NEP compliance among WWID, high injection and sexual risk behaviours in both gender-subgroups, especially in intimate relationships, suggests ongoing HCV and HIV-infection risks. Subgroup-variation in the NEP continuum of care warrants more gender-disaggregated research and tailoring gender-sensitive services may improve prevention, health and retention outcomes.

HCV and HIV co-infection among people who inject drugs in Vietnam

INTRODUCTION

HIV/HCV co-infection in people who inject drugs (PWID) continues to be a major challenge for health care systems and the PWID themselves. PWID have driven the HIV epidemic in Vietnam but information on HIV/HCV co-infection is limited.

METHODS

A cross-sectional study was conducted with 509 PWID recruited in Hanoi from February 2016 to April 2017. Four mutually exclusive groups were defined based on the presence of detectable HCV RNA and positive HIV confirmation. Multiple logistic regression analyses were performed to explore life-time risk behaviors of HCV mono-infection and HIV/HCV co-infection.

RESULTS

The overall prevalence of HIV and HCV infection was 51.08% and 61.69%, respectively. The prevalence of HCV mono-infection and HIV/HCV co-infection was 22.59% and 39.1%, respectively. We found that engaging in methadone maintenance treatment (MMT) was positively associated with HCV mono-infection (aOR = 2.38, 95% Confidential Interval [CI] 1.07 to 5.28) and with at least either HIV or HCV infection (aOR = 2.22, 95% CI 1.08 to 4.56). Ever being incarcerated was significantly associated with HCV mono-infection (aOR = 2.56, 95% CI 1.33 to 4.90) and HIV/HCV co-infection (aOR = 1.90, 95% CI 1.04 to 3.46). Those who had ever shared with and reused syringes/needles were more likely to have HIV/HCV co-infection (aORs = 5.17 and 2.86, P < 0001, respectively) and have either HIV or HCV infection (aORs = 3.42 and 2.37, P < 0001, respectively).

CONCLUSION

Correlates for HCV mono-infection and HIV/HCV co-infection highlight the need to address risk behaviors, expand MMT programs, and establish HCV sentinel surveillance. The high prevalence of HCV and/or HIV co-infection shows a need for access to HCV treatment.

Hepatitis B virus infection among people who use drugs in Iran: a systematic review, meta-analysis, and trend analysis

Background

People who use drugs (PWUD) are considered as one of the main at-risk populations for Hepatitis B virus (HBV) infection. We conducted a systematic review on the prevalence of HBV infection among PWUD in Iran.

Methods

Consistent with PRISMA guideline, international (Medline, Web of Science, Scopus, and Embase) and national (Scientific Information Database) databases were searched using a comprehensive search strategy up to September 2019. The retrieved records were reviewed, and experts were contacted for unpublished studies. Studies on Iranian PWUD reporting HBV surface Antigen (HBsAg) prevalence among people who inject drugs (PWID) and non-injecting PWUD were included. HBsAg prevalence was pooled for PWID and non-injecting PWUD and for other subgroups using random-effects model meta-analysis. The trend of HBV prevalence over time was investigated using meta-regression analysis.

Results

Overall, 35 studies reported data on HBV infection among PWID (33 studies) and non-injecting PWUD (11 studies). The pooled prevalence of HBsAg among PWID was 4.8% (95% CI 3.7–6.2). The only risk factor significantly associated with the odds of positive HBsAg in PWID was the previous history of imprisonment (OR 1.72, 95% CI 1.29–2.30, p value = 0.000). The pooled estimate of HBsAg among non-injecting PWUD was 2.9% (95% CI 2.5–3.2). Time trend analyses showed significant decrease in HBV prevalence among PWID reaching from 8.2% (95% CI 3.9–16.5) in 2004–2006 to 3.1% (95% CI 2.3–4.1) in 2016 and later (b = -0.07; p value = 0.05). No significant trend was detected for non-injecting PWUD.

Conclusion

The prevalence of HBV infection among non-injecting PWUD and even PWID was not considerably higher than the Iranian general population. This might be the result of extensive harm reduction interventions in Iran. However, it seems that there are subgroups of PWID, who do not adequately benefit from existing harm reduction interventions. Future programs should more specifically target these high-risk groups.

A long-acting 3TC ProTide nanoformulation suppresses HBV replication in humanized mice

Nowadays, there is a strong request for the treatment of chronic HBV-infection with direct acting antivirals. Furthermore, prevalent human immunodeficiency virus (HIV-1) and hepatitis B (HBV) co-infections highlight an immediate need for dual long-acting and easily administered antivirals. To this end, we modified lamivudine (3TC), a nucleoside analog inhibitor of both viruses, into a lipophilic monophosphorylated prodrug (M23TC). Prior work demonstrated that nanoformulation of M23TC (NM23TC) enhanced drug stability, controlled dissolution and improved access to sites of viral replication. The present study evaluated the efficacy of a NM23TC in HBV-infected chimeric liver humanized mice. Levels of HBV DNA and HBsAg in plasma were monitored up to 8 weeks posttreatment. A single intramuscular dose of 75 mg/kg 3TC equivalents of nanoformulated NM23TC provided sustained drug levels and suppressed HBV replication in humanized mice for 4 weeks. The results support further development of this long-acting 3TC nanoformulation for HBV treatment and prevention.

Systematic Review and Meta-Analysis of Global Prevalence of HBsAg and HIV and HCV Antibodies among People Who Inject Drugs and Female Sex Workers

The main objective of this study was to evaluate the prevalence of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), hepatitis C virus (HCV) and hepatitis B virus (HBV) and their co-infections among people who inject drugs (PWID) and female sex workers (FSWs). Data sources were searched from January 2008 to October 2018 in different databases. Data were analyzed in Stata 16 software using the Metaprop command. The results showed that the prevalence of HIV, HCV and HBV among PWID was 15%, 60% and 6%, respectively. The prevalence of HIV, HCV and HBV among FSWs was 5%, 1% and 3%, respectively. The prevalence of HIV/HCV, HIV/HBV, HCV/HBV and HIV/HCV/HBV co-infections among PWID was 13%, 2%, 3% and 2%, respectively. The prevalence of HIV/HCV and HIV/HBV co-infections among FSWs was 3% and 1%, respectively. The results show that the prevalence of HCV and HIV infections in PWID and the prevalence of HIV in FSWs is higher than their prevalence in the general population. Interventions for the prevention of HIV and HCV in PWID appear to be poor, and may not be sufficient to effectively prevent HIV and HCV transmission.

HIV prevalence among people who inject drugs (PWID) and related factors in Iran: a systematic review, meta-analysis and trend analysis

AIMS

In Iran, injecting drug use has been the major route of human immunodeficiency virus (HIV) transmission. In order to control the HIV epidemic, a harm reduction program was initiated and has been expanded in recent years. The aim of this study was to provide an updated estimate of HIV prevalence among people who inject drugs (PWID) in Iran, investigate prevalence differences over time and assess prevalence correlates.

DESIGN

A comprehensive systematic review was undertaken in the international, regional and national bibliographic databases in November 2018 and extensive contacts with authors were made. For studies conducted before 2005, we used data from a previous published systematic review.

SETTING

All studies conducted in Iran were included. Recruitment settings included anywhere except studies conducted in infectious diseases wards or HIV counseling centers.

PARTICIPANTS

PWID with any definition utilized in the studies. Thirty-six studies were included, which were conducted in 24 of 31 provinces with a sample size of 22 160 PWID.

MEASUREMENTS

We included studies that had performed HIV testing and had a confirmed diagnosis of HIV through repeating the enzyme-linked immunosorbent assay (ELISA) or Western immunoblot assay (WB). Pooled prevalence of HIV was calculated for the total sample and for different subgroups, by available socio-demographic and behavioral factors. For assessing the trend of HIV prevalence over time, a linear meta-regression model was fitted separately for before 2007 and during 2007 and afterwards.

FINDINGS

The pooled prevalences of HIV before 2007 and in 2007 and afterwards were 14.3% [95% confidence interval (CI) = 9.8-18.9] and 9.7% (95% CI = 7.6-11.9), respectively. HIV prevalence increased until 2005-06 and then slowly declined until 2009-10, which was not significant. Prevalence of HIV was significantly higher in PWID above age 25 years, and in those with history of imprisonment and history of needle/syringe-sharing. HIV prevalence was higher in men than in women, but the difference was insignificant.

CONCLUSION

The prevalence of HIV among people who inject drugs in Iran decreased after 2006 which could, at least in part, be attributed to the development of extensive harm reduction programs in the country.

Associations between national development indicators and the age profile of people who inject drugs: results from a global systematic review and meta-analysis

BACKGROUND

Globally, an estimated 15·6 million people inject drugs. We aimed to investigate global variation in the age profile of people who inject drugs (PWID), identify country-level factors associated with age of PWID, and assess the association between injecting drug use (IDU) in young people and rates of injecting and sexual risk behaviours at the country level.

METHODS

We derived data from a previously published global systematic review done in April, 2016 (and updated in June, 2017) on the percentage of young PWID, duration of IDU, average age of PWID, average age at IDU initiation, and the percentage of PWID reporting sexual and injecting risk behaviours. We also derived national development indicators from World Bank data. We estimated the percentage of young PWID for each country, using a random-effects meta-analysis (DerSimonian-Laird methodology) and generated pooled regional and global estimates for all indicators of IDU in young people. We used univariable and multivariable generalised linear models to test for associations between the age indicators and country urban population growth, youth unemployment percentage, the percentage of PWID who are female, the percentage of the general population aged 15-24 years, Gini coefficient, opioid substitution therapy coverage (per PWID per year), gross domestic product (GDP) per capita (US$1000), and sexual and injecting risk behaviours.

FINDINGS

In the original systematic review, data on age of PWID was reported in 741 studies across 93 countries. Globally, 25·3% (95% uncertainty interval [UI] 19·6-31·8) of PWID were aged 25 years or younger. The highest percentage of young PWID resided in eastern Europe (43·4%, 95% UI 39·4-47·4), and the lowest percentage resided in the Middle East and north Africa (6·9%, 5·1-8·8). At the country level, in multivariable analysis higher GDP was associated with longer median injecting duration (0·11 years per $1000 GDP increase, 95% CI 0·04-0·18; p=0·002), and older median age of PWID (0·13 years per $1000 increase, 0·06-0·20; p<0·0001). Urban population growth was associated with higher age at IDU initiation (1·40 years per annual percentage change, 0·41-2·40). No associations were identified between indicators of IDU in young people and youth unemployment, Gini coefficient, or opioid substitution therapy coverage provision at the country level. No associations were identified between injecting and sexual risk behaviours and age of PWID.

INTERPRETATION

Variation in the age profile of PWID was associated with GDP and urbanisation. Regions with the highest prevalence of young PWID (aged ≤25 years) had low coverage of interventions to prevent the spread of blood-borne viruses. Data quality highlights the need for improvements in monitoring of PWID populations.

FUNDING

Australian National Drug and Alcohol Research Centre, Australian National Health and Medical Research Council, Open Society Foundation, WHO, the Global Fund, UNAIDS, National Institute for Health Research Health Protection Research Unit for Evaluation of Interventions, Wellcome Trust.