Beyond surveillance: a role for respondent-driven sampling in implementation science

Effect of peer-distributed HIV self-test kits on demand for biomedical HIV prevention in rural KwaZulu-Natal, South Africa: a three-armed cluster-randomised trial comparing social networks versus direct delivery

STUDY OBJECTIVE

We investigated two peer distribution models of HIV self-testing (HIVST) in HIV prevention demand creation compared with trained young community members (peer navigators).

METHODS

We used restricted randomisation to allocate 24 peer navigator pairs (clusters) in KwaZulu-Natal 1:1:1: (1) standard of care (SOC): peer navigators distributed clinic referrals, pre-exposure prophylaxis (PrEP) and antiretroviral therapy (ART) information to 18-30 year olds. (2) peer navigator direct distribution (PND): Peer navigators distributed HIVST packs (SOC plus two OraQuick HIVST kits) (3) incentivised peer networks (IPN): peer navigators recruited young community members (seeds) to distribute up to five HIVST packs to 18-30 year olds within their social networks. Seeds received 20 Rand (US$1.5) for each recipient who distributed further packs. The primary outcome was PrEP/ART linkage, defined as screening for PrEP/ART eligibility within 90 days of pack distribution per peer navigator month (pnm) of outreach, in women aged 18-24 (a priority for HIV prevention). Investigators and statisticians were blinded to allocation. Analysis was intention to treat. Total and unit costs were collected prospectively.

RESULTS

Between March and December 2019, 4163 packs (1098 SOC, 1480 PND, 1585 IPN) were distributed across 24 clusters. During 144 pnm, 272 18-30 year olds linked to PrEP/ART (1.9/pnm). Linkage rates for 18-24-year-old women were lower for IPN (n=26, 0.54/pnm) than PND (n=45, 0.80/pnm; SOC n=49, 0.85/pnm). Rate ratios were 0.68 (95% CI 0.28 to 1.66) for IPN versus PND, 0.64 (95% CI 0.26 to 1.62) for IPN versus SOC and 0.95 (95% CI 0.38 to 2.36) for PND versus SOC. In 18-30 year olds, PND had significantly more linkages than IPN (2.11 vs 0.88/pnm, RR 0.42, 95% CI 0.18 to 0.98). Cost per pack distributed was cheapest for IPN (US$36) c.f. SOC (US$64). Cost per person linked to PrEP/ART was cheaper in both peer navigator arms compared with IPN.

DISCUSSION

HIVST did not increase demand for PrEP/ART. Incentivised social network distribution reached large numbers with HIVST but resulted in fewer linkages compared with PrEP/ART promotion by peer navigators.

TRIAL REGISTRATION NUMBER

NCT03751826.

Prevalence and Phylogenetic Characterization of Hepatitis C Virus Among Indian Men Who Have Sex With Men: Limited Evidence for Sexual Transmission

BACKGROUND

Data from high-income countries suggest increasing hepatitis C virus (HCV) prevalence/incidence among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM), but limited data derive from low-and-middle-income countries.

METHODS

We recruited 4994 MSM from 5 states across India using respondent-driven sampling. Logistic regression incorporating respondent-driven sampling weights and machine learning feature selection were used to identify correlates of prevalent HCV, and Bayesian phylogenetic analysis was used to examine genetic clustering.

RESULTS

The median age was 25 years, the HIV prevalence was 7.2%, and 49.3% of participants reported recent unprotected anal intercourse. The HCV prevalence was 1.3% (95% confidence interval, 1.0%-1.6%; site range, 0.2%-3.4%) and was 3.1% in HIV-positive versus 1.1% among HIV-negative men. HCV infection was significantly associated with injection drug use (odds ratio, 177.1; 95% confidence interval, 72.7-431.5) and HIV infection (4.34; 1.88-10.05). Machine learning did not uncover any additional epidemiologic signal. Phylogenetic analysis revealed 3 clusters suggestive of linked transmission; each contained ≥1 individual reporting injection drug use.

CONCLUSIONS

We observed a low HCV prevalence in this large sample of MSM despite a high prevalence of known risk factors, reflecting either the need for a threshold of HCV for sexual transmission and/or variability in sexual practices across settings.

Young people who inject drugs in India have high HIV incidence and behavioural risk: a cross-sectional study

INTRODUCTION

There are limited data on young people who inject drugs (PWID) from low- and middle-income countries where injection drug use remains a key driver of new HIV infections. India has a diverse injection drug use epidemic and estimates suggest that at least half of PWID are ≤30 years of age. We compared injection and sexual risk behaviours and HIV incidence between younger and older PWID and characterized uptake of HIV testing and harm reduction services to inform targeted HIV prevention efforts.

METHODS

We analysed cross-sectional data from 14,381 PWID recruited from cities in the Northeast and North/Central regions of India in 2013 using respondent driven sampling (RDS). We compared "emerging-adult" (18 to 24 years, 26% of sample) and "young-adult" PWID (25 to 30 years, 30% of sample) to older PWID (>30 years, 44% of sample) using logistic regression to evaluate factors associated with three recent risk behaviours: needle-sharing, multiple sexual partners and unprotected sex. We estimated age-stratified cross-sectional HIV incidence using a validated multi-assay algorithm.

RESULTS

Compared to older adults, emerging-adults in the Northeastern states were significantly more likely to share needles (males adjusted odds ratio [aOR] 1.82; females aOR 2.29, p < 0.01), have multiple sexual partners (males aOR 1.56; females aOR 3.75, p < 0.01), and engage in unprotected sex (males aOR 2.29, p < 0.01). In the North/Central states, young-adult males were significantly more likely to needle-share (aOR 1.23, p < 0.05) while emerging-adult males were significantly more likely to have multiple sexual partners (aOR 1.74, p < 0.05). In both regions, emerging-adults had the lowest HIV testing. Participation in harm reduction services was low across all age groups. Annual HIV incidence was higher in emerging- and young-adult PWID in the North/Central region: emerging-adults: 4.3% (95% confidence interval [CI] 3.0, 5.6); young-adults: 4.9% (95% CI 3.7, 6.2); older adults: 2.1% (95% CI 1.4, 2.8).

CONCLUSIONS

Higher HIV incidence and engagement in risky behaviours among younger PWID compared to older PWID, coupled with low utilization of harm reduction services highlight the importance of targeting this population in HIV programming. Age-specific interventions focused on addressing the needs of young PWID are urgently needed to curb the HIV epidemic in this vulnerable population.

Syndemics: A theory in search of data or data in search of a theory?

The concept of a syndemic was proposed more than two decades ago to explain how large-scale social forces might give rise to co-occurring epidemics that synergistically interact to undermine health in vulnerable populations. This conceptual instrument has the potential to help policymakers and program implementers in their endeavors to improve population health. Accordingly, it has become an increasingly popular heuristic for advocacy, most notably in the field of HIV treatment and prevention. However, most empirical studies purporting to validate the theory of syndemics actually do no such thing. Tomori et al. (2018) provide a novel case study from India illustrating how the dominant empirical approach fails to promote deeper understanding about how hazardous alcohol use, illicit drug use, depression, childhood sexual abuse, and intimate partner violence interact to worsen HIV risk among men who have sex with men. In this commentary, I relate the theory of syndemics to other established social science and public health theories of disease distribution, identify possible sources of conceptual and empirical confusion, and provide concrete suggestions for how to validate the theory using a mixed-methods approach. The hope is that more evidence can be mobilized -- whether informed by the theory of syndemics or not -- to improve health and psychosocial wellbeing among vulnerable populations worldwide.

Is there synergy in syndemics? Psychosocial conditions and sexual risk among men who have sex with men in India

Syndemic theory describes the clustering and synergistic interaction of disease driven by contextual and social factors, which worsen health outcomes for a population, and has been applied to men who have sex with men (MSM) and their risk for HIV and other sexually transmitted infections. Recent reviews, however, have critiqued prevailing approaches in syndemic studies that assess only additive associations without evaluation of synergy. Following these suggestions, we compared the traditional additive approach with a test for synergistic association of 5 syndemic conditions (alcohol dependence, illicit drug use, depression, intimate partner violence (IPV), and childhood sexual abuse (CSA)) with unprotected anal intercourse (UAI) and active syphilis infection among 11,771 MSM recruited through respondent driven sampling from 12 cities in India. UAI was assessed via self-report and active syphilis infection was diagnosed by RPR and THPA tests. An additive association was explored using a condition count (range 0-5), and synergy was tested using relative excess risk due to interactions (RERIs) calculated from all 2-way and common 3-way interactions between conditions in adjusted regression models. There was a significant dose response associated with the syndemic count and UAI, and a similar pattern for syphilis, though not statistically significant. RERIs showed synergy for only one pair of conditions for UAI and syphilis, respectively: IPV + depression and alcohol dependence + illicit drug use. In this study, we found an additive association between syndemic conditions and UAI with evidence of synergistic interaction between a pair of psychosocial conditions, and no significant additive association, but a synergistic interaction between another pair of psychosocial conditions for syphilis. Our results lend further support to a critical reassessment of syndemic analyses. Closer attention to the cumulative development, underlying causal pathways, and possible synergistic interaction of co-occurring epidemics through combined qualitative and quantitative methodologies may yield more effective interventions for vulnerable, marginalized populations.

HIV viral load monitoring among key populations in low- and middle-income countries: challenges and opportunities

Introduction

Key populations bear a disproportionate HIV burden and have substantial unmet treatment needs. Routine viral load monitoring represents the gold standard for assessing treatment response at the individual and programme levels; at the population‐level, community viral load is a metric of HIV programme effectiveness and can identify “hotspots” of HIV transmission. Nevertheless, there are specific implementation and ethical challenges to effectively operationalize and meaningfully interpret viral load data at the community level among these often marginalized populations.

Discussion

Viral load monitoring enhances HIV treatment, and programme evaluation, and offers a better understanding of HIV surveillance and epidemic trends. Programmatically, viral load monitoring can provide data related to HIV service delivery coverage and quality, as well as inequities in treatment access and uptake. From a population perspective, community viral load data provides information on HIV transmission risk. Furthermore, viral load data can be used as an advocacy tool to demonstrate differences in service delivery and to promote allocation of resources to disproportionately affected key populations and communities with suboptimal health outcomes. However, in order to perform viral load monitoring for individual and programme benefit, health surveillance and advocacy purposes, careful consideration must be given to how such key population programmes are designed and implemented. For example, HIV risk factors, such as particular sex practices, sex work and drug use, are stigmatized or even criminalized in many contexts. Consequently, efforts must be taken so that routine viral load monitoring among marginalized populations does not cause inadvertent harm. Furthermore, given the challenges of reaching representative samples of key populations, significant attention to meaningful recruitment, decentralization of care and interpretation of results is needed. Finally, improving the interoperability of health systems through judicious use of biometrics or identifiers when confidentiality can be maintained is important to generate more valuable data to inform monitoring programmes.

Conclusions

Opportunities for expanded viral load monitoring could and should benefit all those affected by HIV, including key populations. The promise of the increasing routinization of viral load monitoring as a tool to advance HIV treatment equity is great and should be prioritized and appropriately implemented within key population programmatic and research agendas.

Perspectives on Sexual Identity Formation, Identity Practices, and Identity Transitions Among Men Who Have Sex With Men in India

Men who have sex with men (MSM) remain at high risk for HIV infection. Culturally specific sexual identities, encompassing sexual roles, behavior, and appearance, may shape MSM's experiences of stigmatization and discrimination, and affect their vulnerability to HIV. This multi-site qualitative study (n = 363) encompassing 31 focus group discussions (FGDs) and 121 in-depth interviews (IDIs) across 15 sites in India investigated sexual identity formation, identity practices, and transitions and their implications for HIV prevention. IDIs and FGDs were transcribed, translated, and underwent thematic analysis. Our findings document heterogeneous sexual identity formation, with MSM who have more gender nonconforming behaviors or appearance reporting greater family- and community-level disapproval, harassment, violence, and exclusion. Concealing feminine aspects of sexual identities was important in daily life, especially for married MSM. Some participants negotiated their identity practices in accordance with socioeconomic and cultural pressures, including taking on identity characteristics to suit consumer demand in sex work and on extended periods of joining communities of hijras (sometimes called TG or transgender women). Participants also reported that some MSM transition toward more feminine and hijra or transgender women identities, motivated by intersecting desires for feminine gender expression and by social exclusion and economic marginalization. Future studies should collect information on gender nonconformity stigma, and any changes in sexual identity practices or plans for transitions to other identities over time, in relation to HIV risk behaviors and outcomes.

Epidemiology of HIV and hepatitis C infection among women who inject drugs in Northeast India: a respondent-driven sampling study

BACKGROUND AND AIMS

Despite extensive research on HIV and hepatitis C (HCV) among people who inject drugs (PWID), there remains a gap in knowledge on the burden among women who inject drugs and their unique contexts and risk factors. This analysis compares HIV and HCV prevalence in female and male PWID and estimates injection and sexual risk correlates of prevalent HIV and HCV infection among women in Northeast India.

DESIGN

Cross-sectional sample accrued using respondent-driven sampling.

SETTING

Seven cities in Northeast India, 2013.

PARTICIPANTS

A total of 6457 adult PWID.

MEASUREMENTS

Participants completed an interviewer-administered survey. HIV infection was diagnosed on-site and HCV antibody testing was performed on stored specimens. HIV and HCV prevalence estimates were stratified by gender. Among women, the association of risk correlates with HIV and HCV were estimated using multi-level logistic regression models.

FINDINGS

A total of 796 (15.9%) of the PWID were women, of whom 52.9% [95% confidence interval (CI) = 49.3-56.5%] were HIV-infected and 22.3% (CI = 19.9-24.7%) were HCV-infected. HIV and HCV prevalence among men was 17.4% (CI = 16.9-24.7%) and 30.4% (CI = 31.2-32.0%), respectively. Among women, correlates of HIV were widowhood [adjusted odds ratio (aOR) versus currently married = 4.03, CI = 2.13-7.60] and a higher number of life-time sexual partners (aOR ≥8 versus none = 3.08, CI = 1.07-8.86). Correlates of HCV were longer injection duration (aOR per 10 years = 1.70, CI = 1.25-2.27), injecting only heroin and a combination of drugs (aOR versus pharmaceuticals only = 5.63, CI = 1.68-18.9 and aOR = 2.58, CI = 1.60-4.16, respectively), sharing needles/syringes (aOR = 2.46, CI = 1.29-4.56) and a larger PWID network (aOR ≥ 51 versus 1-5 = 4.17, CI = 2.43-7.17).

CONCLUSIONS

Women who inject drugs in Northeast India have a high HIV prevalence, which was more than double their hepatitis C (HCV) prevalence, an opposite pattern than is observed typically among male PWID. HIV infection is associated with sexual risk factors while injection-related behaviors appear to drive HCV infection.

From Patients to Policy: Population Intervention Effects in Epidemiology

Interest in implementation science and recent calls for consequentialist epidemiology urge epidemiologists to produce work more immediately applicable to public health practice. A clear vocabulary for such approaches is lacking. Here, we present a potential taxonomy of causal effects, distinguishing between "exposure effects" more relevant to patients and individuals; and "population intervention effects" more relevant to public health policy. We discuss this range of effects using figures and a simple numerical example.

The Parasol Protocol: An Implementation Science Study of HIV Continuum of Care Interventions for Gay Men and Transgender Women in Burma/Myanmar

BACKGROUND

Efforts to improve HIV diagnosis and antiretroviral therapy (ART) initiation among people living with HIV and reduce onward transmission of HIV rely on innovative interventions along multiple steps of the HIV care continuum. These innovative methods are particularly important for key populations, including men who have sex with men (MSM) and transgender women (TW). The HIV epidemic in Myanmar is concentrated among key populations, and national efforts now focus on reducing stigma and improving engagement of MSM and TW in HIV prevention and care.

OBJECTIVE

This study aims to test the use of several innovations to address losses in the HIV care continuum: (1) use of respondent-driven sampling (RDS) to reach and engage MSM and TW in HIV testing, (2) HIV self-testing (HIVST) to increase HIV testing uptake and aid early diagnosis of infection, (3) community-based CD4 point-of-care (POC) technology to rapidly stage HIV disease for those who are HIV infected, and (4) peer navigation support to increase successful health system navigation for HIV-infected MSM and TW in need of ART or HIV engagement in care.

METHODS

To assess the effect of HIVST, we will implement a randomized trial in which MSM and TW adults in the greater Yangon metropolitan area who are HIV uninfected will be recruited via RDS (N=366). Participants will complete a baseline socio-behavioral survey and will be randomized to standard, voluntary counseling and testing (VCT) or to HIVST. Biologic specimens will be collected during this baseline visit for confirmatory testing using dried blood spots. Participants will be asked to return to the study office to complete a second study visit in which they will report their HIV test result and answer questions on the acceptability of the assigned testing method. Aim 1 participants with confirmed HIV infection and who are not engaged in care (N=49) will be offered direct enrollment into Aims 2 and 3, which include immediate CD4 POC and the option for peer navigation, respectively. Aims 2 and 3 participants will be prospectively followed for 12 months with data collection including interviewer-administered sociobehavioral survey, CD4 POC, and viral load testing occurring biannually. Participants who accept peer navigation will be compared to those who decline peer navigation. Analyses will estimate the impact of CD4 POC on engagement in care and the impact of peer navigation on ART adherence and viral load.

RESULTS

Formative qualitative research was conducted in June and September 2015 and led to further refinement of recruitment methods, HIVST instructions and counseling, and peer navigation methods. Aim 1 recruitment began in November 2015 with subsequent enrollment into Aims 2 and 3 and is currently ongoing.

CONCLUSIONS

These innovative interventions may resolve gaps in the HIV care continuum among MSM and TW and future implementation may aid in curbing the HIV epidemic among MSM and TW in Myanmar.

HIV decline associated with changes in risk behaviours among young key populations in Nepal: analysis of population-based HIV prevalence surveys between 2001 and 2012

We assessed changes in HIV prevalence and risk behaviours among young key populations in Nepal. A total of 7505 participants (aged 16-24 years) from key populations who were at increased risk of HIV infection (2767 people who inject drugs (PWID); 852 men who have sex with men/transgender (MSM/TG); 2851 female sex workers (FSW) and 1035 male labour migrants) were recruited randomly over a 12-year period, 2001-2012. Local epidemic zones of Nepal (Kathmandu valley, Pokhara valley, Terai Highway and West to Far West hills) were analysed separately. We found a very strong and consistent decline in HIV prevalence over the past decade in different epidemic zones among PWID and MSM/TG in Kathmandu, the capital city, most likely due to a parallel increase in safe needle and syringe use and increased condom use. A decrease in HIV prevalence in 22 Terai highway districts, sharing an open border with India, was also consistent with increased condom use among FSW. Among male labour migrants, HIV prevalence was low throughout the period in the West to Far West hilly regions. Condom use by migrant workers involved with FSW abroad increased while their condom use with Nepalese FSW declined. Other risk determinants such as mean age at starting first injection, injection frequency, place of commercial sex solicitation, their mean age when leaving to work abroad did not change consistently across epidemic zones among the young key populations under study. In Nepal, the decline in HIV prevalence over the past decade was remarkably significant and consistent with an increase in condom use and safer use of clean needles and syringes. However, diverging trends in risk behaviours across local epidemic zones of Nepal suggest a varying degree of implementation of national HIV prevention policies. This calls for continued preventive efforts as well as surveillance to sustain the observed downward trend.

The prevalence and impact of childhood sexual abuse on HIV-risk behaviors among men who have sex with men (MSM) in India

Background

Childhood sexual abuse (CSA) is a significant global public health problem, which is associated with negative psychosocial outcomes and high-risk sexual behaviors in adults. Men who have sex with men (MSM) often report higher prevalence of CSA history than the general population, and CSA may play a key role in MSM’s greater vulnerability to HIV.

Methods

This study examined the prevalence of CSA history and its impact on the number of recent HIV-related risk behaviors (unprotected anal intercourse, high number of male and female sexual partners, alcohol use, drug use, and sex work in prior 6 months) and lifetime risk behaviors and experiences (high number of lifetime male and female sexual partners, early sexual debut, injection drug use, sex work, and intimate partner violence) among 11,788 adult MSM recruited via respondent driven sampling across 12 sites in India, with additional insights from thematic analysis of qualitative research with 363 MSM from 15 sites.

Results

Nearly a quarter (22.4 %) of participants experienced CSA, with substantially higher prevalence of CSA in the South and among kothis (feminine sexual identity). Qualitative findings revealed that older, trusted men may target young and, especially, gender nonconforming boys, and perpetrators’ social position facilitates nondisclosure. CSA may also initiate further same-sex encounters, including sex work. In multivariable analysis, MSM who experienced CSA had 21 % higher rate of recent (adjusted rate ratio [aRR = 1.21], 95 % confidence interval [CI]: 1.14–1.28), and 2.0 times higher lifetime (aRR = 2.04, 95 % CI: 1.75–2.38) HIV-related behaviors/experiences compared with those who did not.

Conclusion

This large, mixed-methods study found high overall prevalence of CSA among MSM (22.4 %), with substantially higher prevalence among MSM residing in the South and among more feminine sexual identities. Qualitative findings highlighted boys’ vulnerabilities to CSA, especially gender nonconformity, and CSA’s role in further sexual encounters, including sex work. Additionally, CSA was associated with an elevated rate of recent, and an even higher rate of lifetime HIV-related risk factors. Our results suggest an acute need for the development of CSA prevention interventions and the integration of mental health services for MSM with histories of CSA as part of HIV-prevention efforts.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3446-6) contains supplementary material, which is available to authorized users.

Getting to 90: linkage to HIV care among men who have sex with men and people who inject drugs in India

UNAIDS set an ambitious target of "90-90-90" by 2020. The first 90 being 90% of those HIV-infected will be diagnosed; the second 90 being 90% of those diagnosed will be linked to medical care and on antiretroviral therapy (ART). While there has been dramatic improvement in HIV testing and ART use, substantial losses continue to occur at linkage-to-care following HIV diagnosis. Data on linkage among men who have sex with men (MSM) and people who inject drugs (PWID) are sparse, despite a greater burden of HIV in these populations. This cross-sectional study was conducted in 27 sites across India. Participants were recruited using respondent-driven sampling and had to be ≥18 years and self-identify as male and report sex with a man in the prior year (MSM) or injection drug use in the prior 2 years (PWID). Analyses were restricted to HIV-infected persons aware of their status. Linkage was defined as ever visiting a doctor for management of HIV after diagnosis. We explored factors that discriminated between those linked and not linked to care using multi-level logistic regression and area under the receiver operating curves (AUC), focusing on modifiable factors. Of 1726 HIV-infected persons aware of their status, 80% were linked to care. Modifiable factors around the time of diagnosis that best discriminated linkage included receiving assistance with HIV medical care (odds ratio [OR]: 10.0, 95% confidence interval [CI]): 5.6-18.2), disclosure of HIV-positive status (OR: 2.8; 95% CI: 2.4-6.1) and receiving information and counseling on management of HIV (OR: 2.3; 95% CI: 1.1-4.6). The AUC for these three factors together was 0.85, higher than other combinations of factors. We identified three simple modifiable factors around the time of diagnosis that could facilitate linkage to care among MSM and PWID in low- and middle-income countries to achieve UNAIDS targets.

Friends, Sisters, and Wives: Social Support and Social Risks in Peer Relationships Among Men Who Have Sex With Men (MSM) in India

Globally, men who have sex with men (MSM) are at high risk for HIV. Many HIV-prevention efforts rely on community outreach and mobilization to engage MSM. This study examines peer relationships and their potential role in HIV prevention through 31 focus group discussions (FGDS) and 121 in-depth interviews (IDIs) with 363 MSM across 15 sites in India. Results indicate that MSM receive social support in friendships, sex-worker collaborations, constructed kin relationships, and romantic partnerships. Access to these relationships, however, is uneven across MSM, and can carry risks of disclosure of same-sex behavior and exclusion based on HIV- positive status. Positive peer relationships can serve as the basis of community empowerment, education, and couple-based interventions for MSM, and peer counselors can also provide a buffer against the social risks of peer relationships and facilitate linkage to care and continued engagement in treatment. These insights can improve HIV interventions for MSM in India and elsewhere.

Community viral load, antiretroviral therapy coverage, and HIV incidence in India: a cross-sectional, comparative study

BACKGROUND

HIV incidence is the best measure of treatment-programme effectiveness, but its measurement is difficult and expensive. The concept of community viral load as a modifiable driver of new HIV infections has attracted substantial attention. We set out to compare several measures of community viral load and antiretroviral therapy (ART) coverage as correlates of HIV incidence in high-risk populations.

METHODS

We analysed data from a sample of people who inject drugs and men who have sex with men, who were participants of the baseline assessment of a cluster-randomised trial in progress across 22 cities in India (ClinicalTrials.gov number NCT01686750). We recruited the study population by use of respondent-driven sampling and did the baseline assessment at 27 community-based sites (12 for men who have sex with men and 15 for people who inject drugs). We estimated HIV incidence with a multiassay algorithm and calculated five community-based measures of HIV control: mean log10 HIV RNA in participants with HIV in a community either engaged in care (in-care viral load), aware of their status but not necessarily in care (aware viral load), or all HIV-positive individuals whether they were aware, in care, or not (population viral load); participants with HIV in a community with HIV RNA more than 150 copies per mL (prevalence of viraemia); and the proportion of participants with HIV who self-reported ART use in the previous 30 days (population ART coverage). All participants were tested for HIV, with additional testing in HIV-positive individuals. We assessed correlations between the measures and HIV incidence with Spearman correlation coefficients and linear regression analysis.

FINDINGS

Between Oct 1, 2012, and Dec 19, 2013, we recruited 26,503 participants, 12,022 men who have sex with men and 14,481 people who inject drugs. Median incidence of HIV was 0·87% (IQR 0·40-1·17) in men who have sex with men and 1·43% (0·60-4·00) in people who inject drugs. Prevalence of viraemia was more strongly correlated with HIV incidence (correlation 0·81, 95% CI 0·62-0·91; p<0·0001) than all other measures, although correlation was significant with aware viral load (0·59, 0·27-0·79; p=0·001), population viral load (0·51, 0·16-0·74; p=0·007), and population ART coverage (-0·54, -0·76 to -0·20; p=0·004). In-care viral load was not correlated with HIV incidence (0·29, -0·10 to 0·60; p=0·14). With regression analysis, we estimated that to reduce HIV incidence by 1 percentage point in a community, prevalence of viraemia would need to be reduced by 4·34%, and ART use in HIV-positive individuals would need to increase by 19·5%.

INTERPRETATION

Prevalence of viraemia had the strongest correlation with HIV incidence in this sample and might be a useful measure of the effectiveness of a treatment programme.

FUNDING

US National Institutes of Health, Elton John AIDS Foundation.

Diverse Rates of Depression Among Men Who Have Sex with Men (MSM) Across India: Insights from a Multi-site Mixed Method Study

Poor psychosocial health contributes to HIV risk behavior and reduced engagement in treatment and care. This study investigates depression and its correlates among 11,992 MSM recruited via respondent driven sampling in 12 cities across India using the Patient Health Questionnaire-9 and supplemented by analysis of qualitative research from 15 sites with 363 MSM. Overall prevalence of depression was 11 %, with substantial variation across sites and subgroups of MSM, and high prevalence of suicidal thoughts among depressed MSM. In multivariable analyses identification as a kothi (feminine sexual identity) [adjusted odds ratio (aOR) = 1.91], disclosure of being MSM to non-family (aOR = 1.7) and family (aOR = 2.4), disclosure of HIV-status (aOR = 5.6), and substance use were associated with significantly higher odds of depression. Qualitative results emphasized dire social consequences of disclosing MSM- and HIV-status, especially to family, including suicidality. Combination prevention interventions should include mental health services that address disclosure, suicidality, and substance use.

Statistical design and analysis plan for an impact evaluation of an HIV treatment and prevention intervention for female sex workers in Zimbabwe: a study protocol for a cluster randomised controlled trial

Background

Pragmatic cluster-randomised trials should seek to make unbiased estimates of effect and be reported according to CONSORT principles, and the study population should be representative of the target population. This is challenging when conducting trials amongst ‘hidden’ populations without a sample frame. We describe a pair-matched cluster-randomised trial of a combination HIV-prevention intervention to reduce the proportion of female sex workers (FSW) with a detectable HIV viral load in Zimbabwe, recruiting via respondent driven sampling (RDS).

Methods

We will cross-sectionally survey approximately 200 FSW at baseline and at endline to characterise each of 14 sites. RDS is a variant of chain referral sampling and has been adapted to approximate random sampling. Primary analysis will use the ‘RDS-2’ method to estimate cluster summaries and will adapt Hayes and Moulton’s ‘2-step’ method to adjust effect estimates for individual-level confounders and further adjust for cluster baseline prevalence. We will adapt CONSORT to accommodate RDS. In the absence of observable refusal rates, we will compare the recruitment process between matched pairs. We will need to investigate whether cluster-specific recruitment or the intervention itself affects the accuracy of the RDS estimation process, potentially causing differential biases. To do this, we will calculate RDS-diagnostic statistics for each cluster at each time point and compare these statistics within matched pairs and time points. Sensitivity analyses will assess the impact of potential biases arising from assumptions made by the RDS-2 estimation.

Discussion

We are not aware of any other completed pragmatic cluster RCTs that are recruiting participants using RDS. Our statistical design and analysis approach seeks to transparently document participant recruitment and allow an assessment of the representativeness of the study to the target population, a key aspect of pragmatic trials. The challenges we have faced in the design of this trial are likely to be shared in other contexts aiming to serve the needs of legally and/or socially marginalised populations for which no sampling frame exists and especially when the social networks of participants are both the target of intervention and the means of recruitment.

The trial was registered at Pan African Clinical Trials Registry (PACTR201312000722390) on 9 December 2013.

HIV care continuum among men who have sex with men and persons who inject drugs in India: barriers to successful engagement

BACKGROUND

We characterize the human immunodeficiency virus (HIV) care continuum for men who have sex with men (MSM) and persons who inject drugs (PWID) across India.

METHODS

We recruited 12 022 MSM and 14 481 PWID across 26 Indian cities, using respondent-driven sampling (September 2012 to December 2013). Participants were aged ≥18 years and either self-identified as male and reported sex with a man in the prior year (MSM) or reported injection drug use in the prior 2 years (PWID). Correlates of awareness of HIV-positive status were characterized using multilevel logistic regression.

RESULTS

A total of 1146 MSM were HIV infected, of whom a median of 30% were aware of their HIV-positive status, 23% were linked to care, 22% were retained before antiretroviral therapy (ART), 16% had started ART, 16% were currently receiving ART, and 10% had suppressed viral loads. There was site variability (awareness range, 0%-90%; suppressed viral load range, 0%-58%). A total of 2906 PWID were HIV infected, of whom a median of 41% were aware, 36% were linked to care, 31% were retained before ART, 20% had started ART, 18% were currently receiving ART, and 15% had suppressed viral loads. Similar site variability was observed (awareness range: 2%-93%; suppressed viral load range: 0%-47%). Factors significantly associated with awareness were region, older age, being married (MSM) or female (PWID), use of other services (PWID), more lifetime sexual partners (MSM), and needle sharing (PWID). Ongoing injection drug use (PWID) and alcohol use (MSM) were associated with lower awareness.

CONCLUSIONS

In this large sample, the major barrier to HIV care engagement was awareness of HIV-positive status. Efforts should focus on linking HIV testing to other essential services.

CLINICAL TRIALS REGISTRATION

NCT01686750.

The utility of population-based surveys to describe the continuum of HIV services for key and general populations

Monitoring the cascade or continuum of HIV services - ranging from outreach services to anti-retroviral treatment - has become increasingly important as the focus in prevention moves toward biomedical interventions, in particular, 'Treatment as Prevention.' The HIV continuum typically utilises clinic-based care and treatment monitoring data and helps identify gaps and inform programme improvements. This paper discusses the merits of a population-based survey-informed continuum of services. Surveys provide individual-level, population-based data by sampling persons both in and outside the continuum, which facilitate the estimation of population fractions, such as the proportion of people living with HIV in care, as well as the examination of determinants for being in or outside the continuum. Survey-informed cascades of services may especially benefit key populations at increased risk for HIV infection for who social marginalisation, criminalisation, and stigma result in barriers to access and retention in services, a low social visibility, mobility, and outreach-based services can compromise clinic-based monitoring. Adding CD4+ T-cell count and viral load measurements to such surveys may provide population-level information on viral load suppression, stage of disease, treatment needs, and population-level transmission potential. While routine clinic-based reporting will remain the mainstay of monitoring, a survey-informed service cascade can address some of its limitations and offer additional insights.

High HIV prevalence and incidence among MSM across 12 cities in India

OBJECTIVE

To characterize prevalence, incidence, and associated correlates of HIV infection among MSM in 12 cities across India.

DESIGN

Cross-sectional sample using respondent-driven sampling from September 2012 to June 2013.

METHODS

A total 12022 MSM (~1000/city) were recruited. Participants had to be at least 18 years, self-identify as male, and report oral/anal intercourse with a man in the prior year. HIV infection was diagnosed using three rapid tests. Cross-sectional HIV incidence was estimated using a multiassay algorithm. All estimates incorporate respondent-driven sampling-II weights.

RESULTS

Median age was 25 years, 45% self-identified as 'panthi' (predominantly penetrative anal intercourse) and 30.6% reported being married to a woman. Weighted HIV prevalence was 7.0% (range: 1.7-13.1%). In multivariate analysis, significantly higher odds of HIV infection was observed among those who were older, had lower educational attainment, were practicing purely receptive anal sex or both receptive and penetrative sex, and those who were herpes simplex virus-2 positive. Of 1147 MSM who tested HIV positive, 53 were identified as recent HIV infections (annualized incidence = 0.87%; range = 0-2.2%). In multivariate analysis, injecting drugs in the prior 6 months, syphilis, and higher number of male partners and fewer female partners were significantly associated with recent HIV infection.

CONCLUSION

We observed a high burden of HIV among MSM in India with tremendous diversity in prevalence, incidence, and risk behaviors. In particular, we observed high incidence in areas with relatively low prevalence suggesting emerging epidemics in areas not previously recognized to have high HIV burden.

High HIV burden among people who inject drugs in 15 Indian cities

BACKGROUND

Injecting drug use has historically been the principal driver of the HIV epidemic in the northeast states of India. However, recent data indicate growing numbers of people who inject drugs (PWIDs) in north and central Indian cities.

METHODS

We conducted face-to-face surveys among PWIDs in seven northeast and eight north/central Indian cities using respondent-driven sampling. We used a rapid HIV-testing protocol to identify seropositive individuals and multiassay algorithm to identify those with recent infection. We used multilevel regression models that incorporated sampling weights and had random intercepts for site to assess risk factors for prevalent and incident (recent) HIV infection.

RESULTS

We surveyed 14 481 PWIDs from 15 Indian cities between January and December 2013. Participants reported high rates of needle/syringe sharing. The median (site range) estimated HIV prevalence and incidence were 18.1% (5.9, 44.9) and 2.9 per 100 person-years (0, 12.4), respectively. HIV prevalence was higher in northeast sites, whereas HIV incidence was higher in north/central sites. The odds of prevalent HIV were over three-fold higher in women than in men. Other factors associated with HIV prevalence or incidence included duration since first injection, injection of pharmaceutical drugs, and needle/syringe sharing.

CONCLUSIONS

The burden of HIV infection is high among PWIDs in India, and may be increasing in cities where injecting drug use is emerging. Women who inject drugs were at substantially higher risk for HIV than men - a situation that may be mediated by dual injection-related and sexual risks.

Burden of hepatitis C virus disease and access to hepatitis C virus services in people who inject drugs in India: a cross-sectional study

BACKGROUND

90% of individuals infected with hepatitis C virus (HCV) worldwide reside in resource-limited settings. We aimed to characterise the prevalence of HCV, HIV/HCV co-infection, and the HCV care continuum in people who inject drugs in India.

METHODS

14 481 people (including 31 seeds--individuals selected as the starting point for sampling because they were well connected in the drug using community) who inject drugs were sampled from 15 cities throughout India using respondent-driven sampling from Jan 2, 2013 to Dec 19, 2013. Data from seeds were excluded from all analyses. HCV prevalence was estimated by the presence of anti-HCV antibodies incorporating respondent-driven sampling weights. HCV care continuum outcomes were self-reported except for viral clearance in treatment-experienced participants.

FINDINGS

The median age of participants was 30 years (IQR 24-36) and 13 608 (92·4%) of 14 449 were men (data were missing for some variables). Weighted HCV prevalence was 5777 (37·2%) of 14 447; HIV/HCV co-infection prevalence was 2085 (13·2%) of 14 435. Correlates of HCV infection included high lifetime injection frequency, HIV positivity, and a high prevalence of people with HIV RNA (more than 1000 copies per mL) in the community. Of the 5777 people who inject drugs that were HCV antibody positive, 440 (5·5%) were aware of their status, 225 (3·0%) had seen a doctor for their HCV, 79 (1·4%) had taken HCV treatment, and 18 (0·4%) had undetectable HCV RNA. Of 12 128 participants who had not previously been tested for HCV, 6138 (50·5%) did not get tested because they had not heard of HCV. In the 5777 people who were HCV antibody positive, 2086 (34·4%) reported harmful or hazardous alcohol use, of whom 1082 (50·4%) were dependent, and 3821 (65·3%) reported needle sharing. Awareness of HCV positive status was significantly associated with higher education, HIV testing history, awareness of HIV positive status, and higher community antiretroviral therapy coverage.

INTERPRETATION

The high burden of HCV and HIV/HCV co-infection coupled with low-access to HCV services emphasises an urgent need to include resource-limited settings in the global HCV agenda. Although new treatments will become available worldwide in the near future, programmes to improve awareness and reduce disease progression and transmission need to be scaled up without further delay. Failure to do so could result in patterns of rising mortality, undermining advances in survival attributed to widespread HIV treatment.

FUNDING

US National Institutes of Health.

Errors in reported degrees and respondent driven sampling: implications for bias

BACKGROUND

Respondent Driven Sampling (RDS) is a network or chain sampling method designed to access individuals from hard-to-reach populations such as people who inject drugs (PWID). RDS surveys are used to monitor behaviour and infection occurence over time; these estimations require adjusting to account for over-sampling of individuals with many contacts. Adjustment is done based on individuals' reported total number of contacts, assuming these are correct.

METHODS

Data on the number of contacts (degrees) of individuals sampled in two RDS surveys in Bristol, UK, show larger numbers of individuals reporting numbers of contacts in multiples of 5 and 10 than would be expected at random. To mimic these patterns we generate contact networks and explore different methods of mis-reporting degrees. We simulate RDS surveys and explore the sensitivity of adjusted estimates to these different methods.

RESULTS

We find that inaccurate reporting of degrees can cause large and variable bias in estimates of prevalence or incidence. Our simulations imply that paired RDS surveys could over- or under-estimate any change in prevalence by as much as 25%. These are particularly sensitive to inaccuracies in the degree estimates of individuals with who have low degree.

CONCLUSIONS

There is a substantial risk of bias in estimates from RDS if degrees are not correctly reported. This is particularly important when analysing consecutive RDS samples to assess trends in population prevalence and behaviour. RDS questionnaires should be refined to obtain high resolution degree information, particularly from low-degree individuals. Additionally, larger sample sizes can reduce uncertainty in estimates.