Ethical considerations in HIV/AIDS biobehavioral surveys that use respondent-driven sampling: illustrations from Lebanon

HIV incidence and impact of interventions among female sex workers and their clients in the Middle East and north Africa: a modelling study

BACKGROUND

The incidence of HIV infection among female sex workers and their clients in the Middle East and north Africa is not well known. We aimed to assess HIV incidence, the contribution of heterosexual sex work networks to these numbers, and the effect of interventions by use of mathematical modelling.

METHODS

In this modelling study, we developed a novel, individual-based model to simulate HIV epidemic dynamics in heterosexual sex work networks. We applied this model to 12 countries in the Middle East and north Africa that had sufficient data to estimate incidence in 2020 and the impact of interventions by 2030 (Algeria, Bahrain, Djibouti, Iran, Libya, Morocco, Pakistan, Somalia, South Sudan, Sudan, Tunisia, and Yemen). Model-input parameters were provided through a systematic review of HIV prevalence, sexual and injecting behaviours, and risk group size estimates of female sex workers and clients. Model output was number of incident HIV infections under different modelling scenarios for each country. Summary statistics were generated on these model output scenarios.

FINDINGS

Based on the output of our model, we estimated a total of 14 604 (95% uncertainty interval [UI] CI 7929-31 819) new HIV infections in the 12 countries in 2020 among female sex workers, clients, and spouses, which constituted 28·1% of 51 995 total new cases in all adults in these 12 countries combined. Model-estimated number of new infections in 2020 in the 12 countries combined was 3471 (95% UI 1295-10 308) in female sex workers, 6416 (3144-14 223) in clients, and 4717 (3490-7288) in client spouses. Contribution of incidence in heterosexual sex work networks to total incidence varied widely, ranging from 3·3% in Pakistan to 71·8% in South Sudan and 72·7% in Djibouti. Incidence in heterosexual sex work networks was distributed roughly equally among female sex workers, clients, and client spouses. Estimated incidence rates among female sex workers per 1000 person-years ranged from 0·4 (95% UI 0·0-7·1) in Yemen to 34·3 (17·2-59·6) in South Sudan. In countries where HIV acquisition through injecting drug use creates substantial exposure for female sex workers who inject drugs, estimated incidence rates per 1000 person-years ranged from 5·1 (95% UI 0·0-35·1) in Iran to 45·8 (0·0-428·6) in Pakistan. The model output predicted that any of the programmed interventions would substantially reduce incidence. Even when a subpopulation did not benefit directly from an intervention, it benefited indirectly through reduction in onward transmission, and indirect impact was often half as large as the direct impact.

INTERPRETATION

Substantial HIV incidence occurs in heterosexual sex work networks across the Middle East and north Africa with client spouses being heavily affected, in addition to female sex workers and clients. Rapid scaling-up of comprehensive treatment and prevention services for female sex workers is urgently needed.

FUNDING

Qatar National Research Fund (a member of Qatar Foundation), the Biostatistics, Epidemiology, and Biomathematics Research Core at the Weill Cornell Medicine-Qatar, Qatar University-Marubeni, the UK Medical Research Council, and the UK Department for International Development.

Identifying the Hidden Population: Former Intravenous Drug Users Who Are No Longer in Contact with Services. "Ask a Friend"

People who, after a period of drug use, have changed their lifestyle and left substance use behind them are a hidden population within our communities. Lack of contact with drug services may mean that they are not tested for hepatitis C (HCV) infection through service-led initiatives and, therefore, may be exposed to the chronic morbidity and risk of death inherent with a legacy of HCV infection. This study utilized respondent-driven sampling (RDS) in a novel fashion to find those at historical risk of HCV. The social networks of people with a history of drug use were mapped, and individuals not currently in contact with services were invited to come forward for testing by members of their social network. The study used a reference group to inform study methodology and communication methods to reach out to this hidden population. One hundred and nine individuals received dry blood spot tests for HCV, 17.4% were antibody positive. Fifty one individuals met the inclusion criteria for this study. One hundred and twenty three invite-to-test coupons were issued; however, only one wave of recruitment consisting of one participant resulted from this method. Using RDS in historical social networks was not effective in this study and did not reach this hidden population and increase testing for HCV. This study is registered with clinicaltrials.gov (Ref NCT03697135).

Epidemiology of Treponema pallidum, Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and herpes simplex virus type 2 among female sex workers in the Middle East and North Africa: systematic review and meta-analytics

BACKGROUND

The epidemiology of sexually transmitted infections (STIs) and the role of commercial heterosexual sex networks in driving STI transmission in the Middle East and North Africa (MENA) region remain largely unknown.

OBJECTIVE

To characterize the epidemiology of Treponema pallidum (syphilis), Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and herpes simplex virus type 2 (HSV-2) among female sex workers (FSWs) in MENA using an in-depth quantitative assessment.

METHODS

A systematic review on ten international, regional, and country-level databases was conducted, and reported following PRISMA guidelines. Pooled prevalences of current and/or ever infection for each STI were estimated using random-effects meta-analyses. Sources of between-study heterogeneity were investigated through random-effects meta-regressions.

RESULTS

One T. pallidum incidence study and 144 STI prevalence studies were identified for 45 812 FSWs in 13 MENA countries. The pooled prevalence of current infection was 12.7% (95% confidence interval (CI) = 8.5%-17.7%) for T. pallidum, 14.4% (95% CI = 8.2%-22.0%) for C. trachomatis, 5.7% (95% CI = 3.5%-8.4%) for N. gonorrhoeae, and 7.1% (95% CI = 4.3%-10.5%) for T. vaginalis. The pooled prevalence of ever infection (seropositivity using antibody testing) was 12.8% (95% CI = 9.4%-16.6%) for T. pallidum, 80.3% (95% CI = 53.2%-97.6%) for C. trachomatis, and 23.7% (95% CI = 10.2%-40.4%) for HSV-2. The multivariable meta-regression for T. pallidum infection demonstrated strong subregional differences, with the Horn of Africa and North Africa showing, respectively 6-fold (adjusted odds ratio (AOR): 6.4; 95% CI = 2.5-16.7) and 5-fold (AOR = 5.0; 95% CI = 2.5-10.6) higher odds of infection than Eastern MENA. There was also strong evidence for declining T. pallidum odds of infection at 7% per year (AOR = 0.93; 95% CI = 0.88-0.98). Study-specific factors including diagnostic method, sample size, sampling methodology, and response rate, were not associated with syphilis infection. The multivariable model explained 48.5% of the variation in T. pallidum prevalence.

CONCLUSIONS

STI infection levels among FSWs in MENA are considerable, supporting a key role for commercial heterosexual sex networks in transmission dynamics, and highlighting the health needs of this neglected and vulnerable population. Syphilis prevalence in FSWs appears to have been declining for at least three decades. Gaps in evidence persist for multiple countries.

HIV epidemiology among female sex workers and their clients in the Middle East and North Africa: systematic review, meta-analyses, and meta-regressions

BACKGROUND

HIV epidemiology among female sex workers (FSWs) and their clients in the Middle East and North Africa (MENA) region is poorly understood. We addressed this gap through a comprehensive epidemiological assessment.

METHODS

A systematic review of population size estimation and HIV prevalence studies was conducted and reported following PRISMA guidelines. Risk of bias (ROB) assessments were conducted for all included studies using various quality domains, as informed by Cochrane Collaboration guidelines. The pooled mean HIV prevalence was estimated using random-effects meta-analyses. Sources of heterogeneity and temporal trends were identified through meta-regressions.

RESULTS

We identified 270 size estimation studies in FSWs and 42 in clients, and 485 HIV prevalence studies in 287,719 FSWs and 69 in 29,531 clients/proxy populations. Most studies had low ROB in multiple quality domains. The median proportion of reproductive-age women reporting current/recent sex work was 0.6% (range = 0.2-2.4%) and of men reporting currently/recently buying sex was 5.7% (range = 0.3-13.8%). HIV prevalence ranged from 0 to 70% in FSWs (median = 0.1%) and 0-34.6% in clients (median = 0.4%). The regional pooled mean HIV prevalence was 1.4% (95% CI = 1.1-1.8%) in FSWs and 0.4% (95% CI = 0.1-0.7%) in clients. Country-specific pooled prevalence was < 1% in most countries, 1-5% in North Africa and Somalia, 17.3% in South Sudan, and 17.9% in Djibouti. Meta-regressions identified strong subregional variations in prevalence. Compared to Eastern MENA, the adjusted odds ratios (AORs) ranged from 0.2 (95% CI = 0.1-0.4) in the Fertile Crescent to 45.4 (95% CI = 24.7-83.7) in the Horn of Africa. There was strong evidence for increasing prevalence post-2003; the odds increased by 15% per year (AOR = 1.15, 95% CI = 1.09-1.21). There was also a large variability in sexual and injecting risk behaviors among FSWs within and across countries. Levels of HIV testing among FSWs were generally low. The median fraction of FSWs that tested for HIV in the past 12 months was 12.1% (range = 0.9-38.0%).

CONCLUSIONS

HIV epidemics among FSWs are emerging in MENA, and some have reached stable endemic levels, although still some countries have limited epidemic dynamics. The epidemic has been growing for over a decade, with strong regionalization and heterogeneity. HIV testing levels were far below the service coverage target of "UNAIDS 2016-2021 Strategy."

Participatory praxis as an imperative for health-related stigma research

BACKGROUND

Participatory praxis is increasingly valued for the reliability, validity, and relevance of research results that it fosters. Participatory methods become an imperative in health-related stigma research, where the constitutive elements of stigma, healthcare settings, and research each operate on hierarchies that push those with less social power to the margins.

DISCUSSION

Particularly for people who are stigmatized, participatory methods balance the scales of equity by restructuring power relationships. As such, participatory praxis facilitates a research process that is responsive to community-identified priorities and creates community ownership of the research, catalyzing policy change at multiple levels and foregrounds, and addresses risks to communities from participating in research. Additionally, through upholding the agency and leadership of communities facing stigma, it can help to mitigate stigma's harmful effects. Health-related stigma research can reduce the health inequities faced by stigmatized groups if funders and institutions require and reward community participation and if researchers commit to reflexive, participatory practices. A research agenda focused on participatory praxis in health-related stigma research could stimulate increased use of such methods.

CONCLUSION

For community-engaged practice to become more than an ethical aspiration, structural changes in the funding, training, publishing, and tenure processes will be necessary.

Overlooked Threats to Respondent Driven Sampling Estimators: Peer Recruitment Reality, Degree Measures, and Random Selection Assumption

Intensive sociometric network data were collected from a typical respondent driven sample (RDS) of 528 people who inject drugs residing in Hartford, Connecticut in 2012-2013. This rich dataset enabled us to analyze a large number of unobserved network nodes and ties for the purpose of assessing common assumptions underlying RDS estimators. Results show that several assumptions central to RDS estimators, such as random selection, enrollment probability proportional to degree, and recruitment occurring over recruiter's network ties, were violated. These problems stem from an overly simplistic conceptualization of peer recruitment processes and dynamics. We found nearly half of participants were recruited via coupon redistribution on the street. Non-uniform patterns occurred in multiple recruitment stages related to both recruiter behavior (choosing and reaching alters, passing coupons, etc.) and recruit behavior (accepting/rejecting coupons, failing to enter study, passing coupons to others). Some factors associated with these patterns were also associated with HIV risk.

Sexual Violence Against Men Who Have Sex with Men in Brazil: A Respondent-Driven Sampling Survey

We estimated the prevalence of sexual violence (SV) experience among men who have sex with men (MSM) in Brazil and identified its associated risk factors. We recruited 3859 MSM through respondent driven sampling. A multivariable hierarchical analysis was performed using an ecological model. The prevalence of having ever experienced SV was 15.9 % (95 % confidence interval [CI] 14.7-17.1). SV experience was independently associated with discrimination due to sexual orientation (odds ratio [OR] 3.05; 95 % CI 2.10-4.42), prior HIV testing (OR 1.81; 95 % CI 1.25-2.63), ≤14 years at first sex (OR 1.86; 95 % CI 1.28-2.71), first sex with a man (OR 1.89; 95 % CI 1.28-2.79), presenting STI symptoms (last year) (OR 1.66; 95 % CI 1.12-2.47), and having suicidal ideas (last 6 months) (OR 2.08; 95 % CI 1.30-3.35). The high levels of SV against MSM in Brazil place them at a markedly higher risk of SV than the general population. Homophobic prejudice is the strongest determinant of SV and urgently needs to be included at the forefront of the national response to SV.

A qualitative analysis of peer recruitment pressures in respondent driven sampling: Are risks above the ethical limit?

BACKGROUND

This paper examines peer recruitment dynamics through respondent driven sampling (RDS) with a sample of injection drug users in Hartford, CT to understand the strategies participants use to recruit peers into a study and the extent to which these strategies may introduce risks above the ethical limit despite safeguards in RDS.

METHODS

Out of 526 injection drug users who participated in a mixed-method RDS methodology evaluation study, a nested sample of 61 participants completed an in-depth semi-structured interview at a 2-month follow-up to explore their experiences with the recruitment process.

RESULTS

Findings revealed that participants used a variety of strategies to recruit peers, ranging from one-time interactions to more persistent strategies to encourage participation (e.g., selecting peers that can easily be found and contacted later, following up with peers to remind them of their appointment, accompanying peers to the study site, etc.). Some participants described the more persistent strategies as helpful, while some others experienced these strategies as minor peer pressure, creating a feeling of obligation to participate. Narratives revealed that overall, the probability of experiencing study-related risks remains relatively low for most participants; however, a disconcerting finding was that higher study-related risks (e.g., relationship conflict, loss of relationship, physical fights, violence) were seen for recruits who participated but switched coupons or for recruits who decided not to participate in the study and did not return the coupon to the recruiter.

CONCLUSIONS

Findings indicate that peer recruitment practices in RDS generally pose minimal risk, but that peer recruitment may occasionally exceed the ethical limit, and that enhanced safeguards for studies using peer recruitment methods are recommended. Suggestions for possible enhancements are described.

Respondent-driven sampling for an adolescent health study in vulnerable urban settings: a multi-country study

The global adolescent population is larger than ever before and is rapidly urbanizing. Global surveillance systems to monitor youth health typically use household- and school-based recruitment methods. These systems risk not reaching the most marginalized youth made vulnerable by conditions of migration, civil conflict, and other forms of individual and structural vulnerability. We describe the methodology of the Well-Being of Adolescents in Vulnerable Environments survey, which used respondent-driven sampling (RDS) to recruit male and female youth aged 15-19 years and living in economically distressed urban settings in Baltimore, MD; Johannesburg, South Africa; Ibadan, Nigeria; New Delhi, India; and Shanghai, China (migrant youth only) for a cross-sectional study. We describe a shared recruitment and survey administration protocol across the five sites, present recruitment parameters, and illustrate challenges and necessary adaptations for use of RDS with youth in disadvantaged urban settings. We describe the reach of RDS into populations of youth who may be missed by traditional household- and school-based sampling. Across all sites, an estimated 9.6% were unstably housed; among those enrolled in school, absenteeism was pervasive with 29% having missed over 6 days of school in the past month. Overall findings confirm the feasibility, efficiency, and utility of RDS in quickly reaching diverse samples of youth, including those both in and out of school and those unstably housed, and provide direction for optimizing RDS methods with this population. In our rapidly urbanizing global landscape with an unprecedented youth population, RDS may serve as a valuable tool in complementing existing household- and school-based methods for health-related surveillance that can guide policy.

Candidate change agent identification among men at risk for HIV infection

Despite limited HIV prevention potency, peer-based programs have become one of the most often used HIV prevention approaches internationally. These programs demonstrate a need for greater specificity in peer change agent (PCA) recruitment and social network evaluation. In the present three-phase study based in India (2009-2010), we first explored the nature of friendship among truck-drivers, a group of men at high risk for HIV infection, in order to develop a thorough understanding of the social forces that contribute to and maintain their personal networks. This was accomplished in the first two study phases through a combination of focus group discussions (n = 5 groups), in-depth qualitative interviews (n = 20), and personal network analyses (n = 25) of truck-drivers to define friendship and deepen our understanding of friendship across geographic spaces. Measures collected in phases I and II included friend typologies, discussion topics, social network influences, advice-giving, and risk reduction. Outcomes were assessed through an iterative process of qualitative textual analysis and social network analysis. The networks of truck-drivers were found to comprise three typologies: close friends, parking lot friends, and other friends. From these data, we developed an algorithmic approach to the identification of a candidate PCA within a high-risk man's personal network. In phase III we piloted field-use of this approach to identify and recruit PCAs, and further evaluated their potential for intervention through preliminary analysis of the PCA's own personal networks. An instrument was developed to translate what social network theory and analysis has taught us about egocentric network dynamics into a real-world methodology for identifying intervention-appropriate peers within an individual's personal network. Our approach can be tailored to the specifications of any high-risk population, and may serve to enhance current peer-based HIV interventions.

Hepatitis B virus and hepatitis C virus infections among female sex workers and men who have sex with men in Lebanon: prevalence, risk behaviour and immune status

BACKGROUND

The aim of our study was to study the prevalence of and the risk behaviours associated with the hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among two high-risk groups: female sex workers (FSW) and men who have sex with men (MSM). Furthermore, since vaccination is a key component of HBV prevention programs, the immune status of HBV infection in these two high-risk groups was evaluated.

METHODS

Participants included in this study were part of a bio-behavioural surveillance study done to assess HIV prevalence among four vulnerable groups in Lebanon. Participants were recruited using a respondent-driven sampling method. The total number of eligible participants were 101 MSM and 103 FSW. Blood samples were collected as dried blood spots and then eluted to be tested for HCV, HBV and HIV by enzyme-linked immunosorbent assay.

RESULTS

None of the 204 individuals tested has been exposed to HCV. In the 101 MSM, only one (0.99%) was an HBsAg carrier and one (0.99%) was confirmed as anti-HIV-positive. Among FSW, 30% showed they were immune to HBV compared with only ~10% among MSM. The distribution of socio-demographic characteristics and potential risk factors in both groups were shown.

CONCLUSION

Our results highlight the urgent need to raise awareness among FSW and MSM and their health care providers of the availability and benefits of HBV vaccination in Lebanon. In addition, and due to the absence of vaccines against HCV and HIV, education programs aiming at behavioural changes should be intensified.

Prevalence and correlates of HIV, syphilis, and hepatitis B and C infection and harm reduction program use among male injecting drug users in Kabul, Afghanistan: A cross-sectional assessment

Background

A nascent HIV epidemic and high prevalence of risky drug practices were detected among injecting drug users (IDUs) in Kabul, Afghanistan from 2005-2006. We assessed prevalence of HIV, hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), syphilis, and needle and syringe program (NSP) use among this population.

Methods

IDUs were recruited between June, 2007 and March, 2009 and completed questionnaires and rapid testing for HIV, HCV, HBsAg, and syphilis; positive samples received confirmatory testing. Logistic regression was used to identify correlates of HIV, HCV, and current NSP use.

Results

Of 483 participants, all were male and median age, age at first injection, and duration of injection were 28, 24, and 2.0 years, respectively. One-fifth (23.0%) had initiated injecting within the last year. Reported risky injecting practices included ever sharing needles/syringes (16.9%) or other injecting equipment (38.4%). Prevalence of HIV, HCV Ab, HBSAg, and syphilis was 2.1% (95% CI: 1.0-3.8), 36.1% (95% CI: 31.8-40.4), 4.6% (95% CI: 2.9-6.9), and 1.2% (95% CI: 0.5-2.7), respectively. HIV and HCV infection were both independently associated with sharing needles/syringes (AOR = 5.96, 95% CI: 1.58 - 22.38 and AOR = 2.33, 95% CI: 1.38 - 3.95, respectively). Approximately half (53.8%) of the participants were using NSP services at time of enrollment and 51.3% reported receiving syringes from NSPs in the last three months. Current NSP use was associated with initiating drug use with injecting (AOR = 2.58, 95% CI: 1.22 - 5.44), sharing injecting equipment in the last three months (AOR = 1.79, 95% CI: 1.16 - 2.77), prior incarceration (AOR = 1.57, 95% CI: 1.06 - 2.32), and greater daily frequency of injecting (AOR = 1.40 injections daily, 95% CI: 1.08 - 1.82).

Conclusions

HIV and HCV prevalence appear stable among Kabul IDUs, though the substantial number having recently initiated injecting raises concern that transmission risk may increase over time. Harm reduction programming appears to be reaching high-risk drug user populations; however, monitoring is warranted to determine efficacy of prevention programming in this dynamic environment.

HIV/AIDS among female sex workers, injecting drug users and men who have sex with men in Lebanon: results of the first biobehavioral surveys

OBJECTIVES

To measure HIV prevalence and associated risk factors among female sex workers, injecting drug users (IDUs) and men who have sex with men (MSM) in Lebanon and the prevalence of hepatitis B virus and hepatitis C virus among IDUs.

METHODS AND DESIGN

A cross-sectional survey of 135 female sex workers, 81 IDUs and 101 MSM was recruited using respondent-driven sampling. A structured interview was conducted by members of nongovernmental organizations working with these populations and blood was collected for serological testing.

RESULTS

HIV prevalence was 3.7% among MSM but no HIV cases were detected among female sex workers or IDUs. Among IDUs, prevalence of hepatitis C virus antibody was 51% and prevalence of hepatitis B virus surface antigen was 5%. Three-quarters of MSM had nonregular male sexual partners during the last year but only 39% reported using a condom every time. There was evidence of overlapping HIV risk: 36% of MSM and 12% of IDUs reported that they had sold sex. Previous testing for HIV was lowest among MSM (at 22%) despite their having the highest level both of knowledge about HIV and of perception of being at risk of HIV infection (67%).

CONCLUSION

Prevention efforts at greater scale are needed to reach these at-risk populations in Lebanon. These should target MSM in particular, including access to HIV testing, but will need to address and overcome stigma. For IDUs, surveillance and prevention efforts should integrate both hepatitis C virus and HIV.

Prevalence of HIV/HCV/HBV infections and drug-related risk behaviours amongst IDUs recruited through peer-driven sampling in Iran

BACKGROUND

The control of blood-borne infections including HIV and hepatitis C (HCV) amongst injecting drug users (IDUs) is a challenge for health authorities in Iran. Hence, more reliable estimates of the levels of blood-borne infections and their associated factors are critically needed.

METHODS

Active IDUs were recruited using peer-driven sampling in a bio-behavioural survey in 2008. Over 8 weeks, data were collected from adults living in a city in Isfahan Province who had injected drugs in the past month. Participants provided a whole blood sample and answered questions on sexual and drug-related risk characteristics. Participants were provided post-test counselling and a non-monetary incentive for their participation. Excluding two inactive cases, the initial recruits resulted in 2-8 waves of recruitment.

RESULTS

Overall, 118 IDUs including three females participated. The estimated population proportions of HIV, hepatitis B, and HCV infections were 0.7% (95% CI, 0.6-2.3), 0.7% (95% CI, 0.1-2.1), and 59.4% (95% CI, 47.4-68.7), respectively. Responses indicated that 31% (95% CI, 20-44.5) of the IDUs ever shared a needle/syringe for drug injection, and 77% (95% CI, 65-84) had ever injected an addictive solution marketed widely as Temgesic. Multivariate analyses revealed that the high prevalence of HCV infection amongst IDUs is associated with the lifetime duration of drug injection (AOR, 1.17; 95% CI, 1.01-1.34) and with having injected Temgesic (AOR, 4.73; 95% CI, 1.52-14.69).

CONCLUSION

Our experience in Iran indicates that IDUs can be recruited effectively in a bio-behavioural survey through peer-driven sampling and using only a single primary incentive. The high prevalence of HCV associated with injecting Temgesic is important evidence for harm-reduction policies in Iran.