Respondent-driven Sampling Study Research Articles

HIV testing cascade among men who have sex with men at higher HIV risk in Serbia

Abstract Background Successful HIV prevention requires motivation, access, and effective use by priority populations. Accessible and non-stigmatizing HIV voluntary counseling and testing (VCT) is the first step towards timely diagnosis. In Serbia, there is a concentrated HIV epidemic among men who have sex with men (MSM), with 49.2% of new diagnoses being detected late in 2021, based on initial CD4 cell count. We examined key aspects related to HIV testing among a high-risk sample of Serbian MSM to improve national HIV prevention guidelines. Methods A bio-behavioral cross-sectional respondent-driven sampling study among MSM in 4 cities in Serbia was conducted in 2021 (N = 1,300). We analyzed HIV testing among MSM who had unprotected anal sexual intercourse (UAI) in the last 12 months. The motivation pillar was operationalized as adequate knowledge of where VCT services can be obtained, the access pillar was operationalized as having ever had HIV testing, and the effective use of the VCT service pillar was operationalized as HIV testing in the last 6 months. Results Of all MSM reached, 63.8% had practiced UAI in the last 12 months, of whom 66.47% knew where to access VCT services. Of these, 88.9% had even been tested for HIV, yet only a quarter (25.5%) had been tested in the last 6 months. Therefore, only 15.1% of MSM who practiced UAI in the last 12 months had been recently tested for HIV. Conclusions HIV testing rate is high among Serbian MSM if they have adequate knowledge of where VCT services can be obtained. However, even though community-based VCT among MSM is subsidized by the Ministry of Health of the Republic of Serbia, the effective use of the VCT services is very low among high-risk MSM. This suggests that VCT service promotion must be transformed to be both visible and culturally sensitive to the Serbian MSM community. VCT protocols should also encourage regular testing (at least every 6 months) for those most at risk for HIV acquisition.

Assessment of Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis prevalence using a molecular Point of Care: Findings from a respondent driven sampling study among MSM.

Due to the limited data available within the Moroccan context, the aim of the study was therefore to estimate the prevalence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) infection and co-infection among men who have sex with men (MSM) as well as to update the behavioral indicators for this population. During the period of November 2020 to January 2021, 275 and 303 MSM in Agadir and Fes respectively, were recruited by using respondent-driven sampling protocol (RDS). Eligibility criteria for participants included men identified as having anal sex with another man in the last 6 months, aged 18 years or older and residing in either Agadir or Fes, regardless of their nationality, for the past 6 months.Anal swabs were collected from 445 respondents for molecular investigation of CT, NG, and TV. GeneXpert (Cepheid, USA) was used to test all samples. A survey on the socio-demographic, and risk behavior was then administered to participants. Most MSM subjects were identified as being young, and homosexual. CT prevalence was 11.3% (95%CI, 7.2 to 15.4) and 12.5% (95%CI, 7.5 to 17.5) in Agadir and Fes respectively; NG was 13.3% (95%CI, 8.5 to 18.1) in Agadir and 5.5% (95%CI, 1.9 to 9.2) in Fes. Meanwhile, TV prevalence was 0.4% (95%CI, 0 to 1.1) in Agadir and 0.2% (95%CI, -0.2 to 0.6) in Fes. A CT/NG co-infection was found in 4.5% (95%CI, 3.5 to 5.9) of cases in Agadir and 2.7% (95%CI, 1.9 to 3.9), in Fes. It follows that a regular risk assessment and Sexually Transmitted Infectious (STIs) screening should be administered in these two cities as part of a global strategy to enhance the sexual health of the key populations in question.

Gynecological Care Among Brazilian Women Who Have Sex with Women: A Respondent-Driven Sampling Study.

Purpose: This study aimed to describe the gynecological care provided to Brazilian women who have sex with women (WSW). Methods: Respondent-driven sampling was used to recruit Brazilian WSW. The survey questions, concerning gynecological care, were designed in Portuguese by medical professionals, medical students, and LGBTQIA+ community members, including the authors. The statistical analyses were weighted to account for the likelihood of recruitment. Results: From January to August of 2018, 299 participants were recruited in 14 recruitment waves. The mean age of the WSW was 25.3 years. Most (54.9%) identified as lesbian and had been involved in past-year sexual intercourse mainly with cisgender women (86.1%). The WSW also reported having sex with cisgender men (22.2%), transgender men (5.3%), nonbinary people (2.3%), and transgender women (5.3%) in the last year. More than a quarter of the WSW did not have regular appointments with a gynecologist: 8.0% (95% confidence interval [CI] = 4.2-11.6) and 19% (95% CI = 12.8-25.2) stated that they had never gone to the gynecologist or they had only gone for emergencies, respectively. Almost one-third had never had cervical cancer screening (cervical cytology, Pap test or Pap smear). Most women justified avoiding the test because they felt healthy, thought it would hurt, or feared a health professional might mistreat them. Conclusion: Gynecologists should avoid heteronormative assumptions, inquire about sexual practices, orientation, and identity separately, and provide Pap tests as advised to WSW.

Respondent- Driven Sampling to Assess Cumulative Lifetime Incidence of Abortion in Soweto, South Africa: A Methodological Assessment.

Respondent-driven sampling (RDS) is a potential strategy for addressing challenges in accurate abortion incidence estimation, but relies on often untested assumptions. We conducted an RDS study to estimate the cumulative lifetime abortion incidence in Soweto, South Africa, evaluate whether RDS assumptions were met, and compare RDS estimates of incidence to estimates adjusted for employment and age based on census data. A total of 849 participants were recruited from 11 seeds between April and December 2018. The assumptions that individuals can identify target population members and approximation of sampling with replacement was met. There were minor violations of the assumptions of seed independence from the final sample, and reciprocity of ties. Assumptions of accurate degree reporting and random recruitment were not met. Failure to meet assumptions yielded a sample with different employment characteristics than the target population, which was not resolved by standard RDS methods. The RDS estimate of cumulative lifetime abortion incidence was 12.1% (95% CI: 9.8%, 14.3%), and the employment-adjusted estimate was 16.9% (95% CI: 12.8%, 22.1%). We caution researchers in using RDS for representative estimates of abortion incidence. Post-survey weights to adjust for differences in characteristics between the sample and target population may yield more representative results.

Improving web-based respondent-driven sampling performance among men who have sex with men in the Netherlands.

Respondent-driven sampling (RDS) uses the social network of participants to sample people of populations that can be challenging to engage. While in this context RDS offers improvements on standard sampling methods, it does not always generate a sufficiently large sample. In this study we aimed to identify preferences of men who have sex with men (MSM) in the Netherlands regarding surveys and recruitment to studies with the subsequent goal of improving the performance of web-based RDS in MSM. A questionnaire about preferences with respect to various aspects of an web-based RDS study was circulated among participants of the Amsterdam Cohort Studies, a study among MSM. The duration of a survey and the type and amount of participation reward were explored. Participants were also asked about their preferences regarding invitation and recruitment methods. We used multi-level and rank-ordered logistic regression to analyze the data and identify the preferences. The majority of the 98 participants were older than 45 years (59.2%), were born in the Netherlands (84.7%), and had a university degree (77.6%). Participants did not have a preference regarding the type of participation reward, but they preferred to spend less time on a survey and to get a higher monetary reward. Sending a personal email was the preferred option to getting invited or inviting someone to a study, while using Facebook messenger was the least preferred option. There are differences between age groups: monetary rewards were less important to older participants (45+) and younger participants (18-34) more often preferred SMS/WhatsApp to recruit others. When designing a web-based RDS study for MSM, it is important to balance the duration of the survey and the monetary reward. If the study takes more of a participants time, it might be beneficial to provide a higher incentive. To optimize expected participation, the recruitment method should be selected based on the targeted population group.

HIV, sexual violence, and termination of pregnancy among adolescent and adult female sex workers in Malawi: A respondent-driven sampling study.

Female Sex Workers (FSWs) are a hard-to-reach and understudied population, especially those who begin selling sex at a young age. In one of the most economically disadvantaged regions in Malawi, a large population of women is engaged in sex work surrounding predominantly male work sites and transport routes. A cross-sectional study in February and April 2019 in Nsanje district used respondent driven sampling (RDS) to recruit women ≥13 years who had sexual intercourse (with someone other than their main partner) in exchange for money or goods in the last 30 days. A standardized questionnaire was filled in; HIV, syphilis, gonorrhea, and chlamydia tests were performed. CD4 count and viral load (VL) testing occurred for persons living with HIV (PLHIV). Among 363 study participants, one-quarter were adolescents 13-19 years (25.9%; n = 85). HIV prevalence was 52.6% [47.3-57.6] and increased with age: from 14.7% (13-19 years) to 87.9% (≥35 years). HIV status awareness was 95.2% [91.3-97.4], ART coverage was 98.8% [95.3-99.7], and VL suppression 83.2% [77.1-88.0], though adolescent FSWs were less likely to be virally suppressed than adults (62.8% vs. 84.4%). Overall syphilis prevalence was 29.7% [25.3-43.5], gonorrhea 9.5% [6.9-12.9], and chlamydia 12.5% [9.3-16.6]. 72.4% had at least one unwanted pregnancy, 17.9% had at least one abortion (40.1% of which were unsafe). Half of participants reported experiencing sexual violence (SV) (47.6% [42.5-52.7]) and more than one-tenth (14.2%) of all respondents experienced SV perpetrated by a police officer. Our findings show high levels of PLHIV-FSWs engaged in all stages of the HIV cascade of care. The prevalence of HIV, other STIs, unwanted pregnancy, unsafe abortion, and sexual violence remains extremely high. Peer-led approaches contributed to levels of ART coverage and HIV status awareness similar to those found in the general district population, despite the challenges and risks faced by FSWs.

Incidence of and Experiences with Abortion Attempts in Soweto, South Africa: Respondent-Driven Sampling Study.

Estimation of abortion incidence, particularly in settings where most abortions occur outside of health facility settings, is critical for understanding information gaps and service delivery needs in different settings. However, the existing methods for measuring out-of-facility abortion incidence are plagued with methodological challenges. Respondent-driven sampling (RDS) may offer a methodological improvement in the estimation of abortion incidence. In this study, we tested the feasibility of using RDS to recruit participants into a study about abortion and estimated the proportion of people who ever attempted abortion as well as 1-year and 5-year incidence of abortion (both in-facility and out-of-facility settings) among women of reproductive age in Soweto, South Africa. Participants were eligible if they identified as a woman; were aged between 15 and 49 years; spoke English, Tswana, isiZulu, Sotho, or Xhosa; and lived in Soweto. Working with community partners, we identified 11 seeds who were provided with coupons to refer eligible peers to the study. Upon arrival at the study site, the recruits completed an interviewer-administered questionnaire that solicited information about demographic characteristics, social network composition, health behaviors, sexual history, pregnancy history, and experience with abortion; recruits also received 3 recruitment coupons. Recruitment was tracked using coupon numbering. We used the RDS-II estimator to estimate the population proportions of demographic characteristics and our primary outcome, the proportion of people who ever attempted abortion. Between April 4, 2018, and December 17, 2018, 849 eligible participants were recruited into the study. The estimated proportion of people who ever attempted abortion was 12.1% (95% CI 9.7%-14.4%). A total of 7.1% (95% CI 5.4%-8.9%) reported a facility-based abortion, and 4.4% (95% CI 3.0%-5.8%) reported an out-of-facility abortion. The estimated proportion of people who ever attempted abortion of 12% (102/849) in our study likely represents a substantial underestimation of the actual proportion of abortion attempts among this study population-representing a failure of the RDS method to generate more reliable estimates of abortion incidence in our study. We caution against the use of RDS to measure the incidence of abortion because of persistent concerns with underreporting but consider potential alternative applications of RDS with respect to the study of abortion.

Sexual and reproductive health needs and practices of female sex workers in Papua New Guinea: findings from a biobehavioral survey Kauntim mi tu (‘Count me too’)

BackgroundLittle research has explored the sexual and reproductive health (SRH) experience of female sex workers (FSW), including girls aged < 18 years who are commercially sexually exploited (CSE), in Papua New Guinea (PNG). This paper describes the SRH history of FSW and CSE girls and factors associated with their use of moderately or highly effective contraceptive methods in three settings in PNG.MethodsFrom 2016 to 2017, respondent-driven sampling (RDS) surveys were conducted among FSW and CSE girls in Port Moresby, Lae, and Mt. Hagen. FSW and CSE girls who were born female, aged ≥12 years, sold or exchanged vaginal sex in the past 6 months, spoke English or Tok Pisin, and had a valid RDS study coupon were eligible to participate. Interviews were conducted face-to-face and participants were offered rapid routine HIV and syphilis testing. Survey logistic regression procedures were used to identify factors associated with the use of moderately or highly effective contraceptive methods. Weighted data analysis was conducted.ResultsA total of 2901 FSW and CSE girls (Port Moresby, 673; Lae, 709; and Mt. Hagen, 709) were enrolled. The proportion using moderately or highly effective contraceptive methods was 37.7% in Port Moresby, 30.9% in Lae, and 26.5% in Mt. Hagen. After adjusting for covariates, factors significantly associated with the use of moderately or highly effective contraceptive methods in Port Moresby were being age 20–24, being married, being divorced or separated, having one or more dependent children, being away from home for more than 1 month in the last 6 months, and having tested HIV negative. No factors were significantly associated in Lae or Mt. Hagen. ANC attendance amongst FSW and CSE girls who gave birth in last 3 years was highest in Port Moresby at 91.2%. HIV testing was inconsistently and inadequately offered at ANC across the three cities.ConclusionsKauntim mi tu provides much-needed insight into the SRH experiences of FSW and CSE girls in PNG, where their use of moderately or highly effective contraceptive methods is low. We hope to shed light on the complicated reality they face due to illegality of sex work and multitude of complex healthcare experiences.

Brief Report: Self-Reported Knowledge of HIV Status Among Cisgender Male Sex Partners of Transgender Women in Lima, Peru.

Knowledge of HIV status is a critical first step in the HIV care cascade. Cisgender male sex partners of transgender women (MSTW) are at a disproportionately high risk of HIV, but little is known about their access to HIV testing or knowledge of HIV status. We used cross-sectional data from a respondent-driven sampling study to analyze self-reported HIV status and predictors of knowledge of HIV status among MSTW in Lima, Peru. Mixed-effects models were used to generate crude and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) for the association between knowledge of HIV status and predictors of interest, including sociodemographics and recent sexual behavior. From February to July 2018, 196 eligible MSTW enrolled, of which 90 (46%) reported not knowing their HIV status. Recent casual or 1-time partners were reported by 84% of MSTW and 54% reported purchasing sex. In adjusted analyses, MSTW participants were less likely to know their HIV status if they reported buying sex (aPR 0.43, 95% CI: 0.32 to 0.59) or reported ≥16 recent sex partners compared with ≤5 partners [aPR 0.32, (0.20 to 0.50)]. Those who reported male sex partners were 80% more likely to know their status [aPR 1.80, (1.33 to 2.44)]. Reported knowledge of HIV status was low among MSTW in Lima, and unknown HIV status was associated with behaviors linked to HIV acquisition. MSTW who reported male partners were more likely to know their status, potentially indicating that HIV testing is more accessible to men who have sex with men.

Precarious work among personal support workers in the Greater Toronto Area: a respondent-driven sampling study.

Background:The COVID-19 pandemic has highlighted the role of personal support workers (PSWs) in health care, as well as their work conditions. Our study aimed to understand the characteristics of the PSW workforce, their work conditions and their job security, as well as to explore the health of PSWs and the impact of precarious employment on their health.Methods:Our community-based participatory action research focused on PSWs in the Greater Toronto Area. We administered an online, cross-sectional survey between June and December 2020 using respondent-driven sampling. Data on sociodemographics, employment precarity, worker empowerment and health status were collected. We assessed the association between precarious employment and health using multivariable logistic regression models.Results:We contacted 739 PSWs, and 664 consented to participate. Overall, 658 (99.1%) completed at least part of the survey. Using data adjusted for our sampling approach, the participants were predominantly Black (76.5%, 95% confidence interval [CI] 68.2%–84.9%), women (90.1%, 95% CI 85.1%–95.1%) and born outside of Canada (97.4%, 95% CI 94.9%–99.9%). Most worked in home care (43.9%, 95% CI 35.2%–52.5%) or long-term care (34.5%, 95% CI 27.4%–42.0%). Although most participants had at least some postsecondary education (unadjusted proportion = 83.4%, n = 529), more than half were considered low income (55.1%, 95% CI 46.3%–63.9%). Most participants were precariously employed (86.5%, 95% CI 80.7%–92.4%) and lacked paid sick days (89.5%, 95% CI 85.8%–93.3%) or extended health benefits (74.1%, 95% CI 66.8%–81.4%). Nearly half of the participants described their health as less than very good (46.7%, 95% CI 37.9%–55.5%). Employment precarity was significantly associated with higher risk of depression (odds ratio 1.02, 95% CI 1.01–1.03).Interpretation:Despite being key members of health care teams, most PSWs were precariously employed with low wages that keep them in poverty; the poor work conditions they faced could be detrimental to their physical and mental health. Equitable strategies are needed to provide decent work conditions for PSWs and to improve their health.

HIV care continuum among cisgender and transgender women sex workers in Greater Kuala Lumpur, Malaysia

ABSTRACT An estimated 37,000 cisgender and transgender women work as sex workers in Malaysia, a population that has been disproportionately affected by the HIV epidemic. Although Malaysia provides no-cost antiretroviral therapy (ART) to people with HIV, little is known about sex workers’ engagement in the HIV care continuum. We analyzed data from 57 HIV-infected cisgender women (n = 33) and transgender women (n = 24) sex workers from a respondent-driven sampling study on HIV prevalence among sex workers in Kuala Lumpur, Malaysia. We examined the proportion of women who were newly diagnosed with HIV, had a baseline CD-4 count test, were initiated and retained on antiretroviral treatment (ART). Overall, only 26.3% had ever been HIV tested and almost 60% were newly diagnosed. Only a small proportion of cisgender (15.2%) and transgender (12.5%) women were currently taking ART. Interventions to enhance sex workers’ engagement in the HIV care continuum are urgently needed. Deployment of evidence-based strategies to improve linkage and retention in HIV care should be adapted to address the unique needs of this important key population.

A Bayesian framework for modelling the preferential selection process in respondent-driven sampling

In sampling designs that utilize peer recruitment, the sampling process is partially unknown and must be modelled to make inference about the population and estimate standard outcomes like prevalence. We develop a Bayesian model for the recruitment process for respondent-driven sampling (RDS), a network sampling methodology used worldwide to sample hidden populations that are not reachable by conventional sampling techniques, including those at high risk for HIV/AIDS. Current models for the RDS sampling process typically assume that recruitment occurs randomly given the population social network, but this is likely untrue in practice. To model preferential selection on covariates, we develop a sequential two-sided rational choice framework, which allows generative probabilistic network models to be created for the RDS sampling process. In the rational choice framework, members of the population make recruitment and participation choices based on observable nodal and dyadic covariates to maximize their utility given constraints. Inference is made about recruitment preferences given the observed recruitment chain in a Bayesian framework by incorporating the latent utilities and sampling from the joint posterior distribution via Markov chain Monte Carlo. We present simulation results and apply the model to an RDS study of Francophone migrants in Rabat, Morocco.

General regression methods for respondent-driven sampling data.

Respondent-driven sampling is a variant of link-tracing sampling techniques that aim to recruit hard-to-reach populations by leveraging individuals’ social relationships. As such, a respondent-driven sample has a graphical component which represents a partially observed network of unknown structure. Moreover, it is common to observe homophily, or the tendency to form connections with individuals who share similar traits. Currently, there is a lack of principled guidance on multivariate modelling strategies for respondent-driven sampling to address peer effects driven by homophily and the dependence between observations within the network. In this work, we propose a methodology for general regression techniques using respondent-driven sampling data. This is used to study the socio-demographic predictors of HIV treatment optimism (about the value of antiretroviral therapy) among gay, bisexual and other men who have sex with men, recruited into a respondent-driven sampling study in Montreal, Canada.

Determinants and consequences of heavy episodic drinking among female sex workers in Ethiopia: A respondent-driven sampling study.

Female sex workers (FSW), due to their working conditions, have an increased likelihood of heavy episodic drinking (HED), which is associated with risky sexual behavior. Nevertheless the specific contribution of HED to risky sexual behavior among FSWs in Ethiopia is not well documented for prevention activities. The purpose of this study was to explore the determinants and consequences of HED among FSWs in Ethiopia. A cross-sectional study using respondent-driven sampling was conducted among 4886 FSWs in 11 major towns in Ethiopia in 2014. A structured interview was performed, and data were examined using descriptive statistics and multiple logistic regression analyses. Most (66%) FSWs consumed alcohol, and the prevalence of HED was 29.1%. Compared to street-based FSWs, those who worked in bars/hotels and local drinking houses had 2.19 and 1.29 times higher odds of HED, respectively. FSWs who started selling sex when younger than 18 years (compared to those who started when older than 25 years) and those who were forced into selling sex had 1.48 and 2.91 times higher odds of HED, respectively. FSWs with more income from selling sex and FSWs who chewed khat reported increased odds of HED. Moreover, FSWs with experience of HED reported 1.27 and 1.44 times higher odds of physical beating and condom breakage/slippage, respectively. Furthermore, the population attributable risk fraction of HED among FSWs showed that 6.2% of physical beating and 8.9% of condom breakage/slippage could be attributed to HED. In general, several factors increase the experience of HED, and HED in turn increases the likelihood of violence and condom breakage. These factors could inform programs and intervention activities among FSWs populations.

Fish consumption and awareness of fish advisories among Burmese refugees: A respondent-driven sampling study in Milwaukee, Wisconsin

BackgroundSince 2000, more than 6000 Burmese refugees were resettled in Wisconsin. The Burmese diet is traditionally rich in fish and fish products, and studies show that Burmese refugees continue to rely on local waterbodies for food. Given that Wisconsin has five Areas of Concern (AOC) that are severely affected by pollution, long-term exposure to contaminants in sport-caught fish is a health concern. To better understand fish consumption among Burmese refugees, we conducted a biomonitoring study in Milwaukee. The present study examined Burmese refugees’ fish consumption habits and awareness of fish advisories. MethodsWe used respondent-driven sampling (RDS) methodology to recruit Burmese refugees in Milwaukee. RDS Analysis Tool 7.1 was used to obtain adjusted population estimates for demographic characteristics, fish consumption habits, and awareness of fish advisories. Homophily and equilibrium were investigated to evaluate the effectiveness of RDS in recruitment. ResultsInitiated by five active seeds, we recruited 103 respondents to participate in the study. Respondents had a strong preference to recruit those with the same ethnicity (Homophily-score: 0.614 to 0.699) and a relatively weak preference to recruit those with the same sex (Homophily-score: 0.188 to 0.222) to participate in our study. The majority (72.5%) of respondents were women of childbearing age (WCBA). Most (68.5%) had 8th grade or less education. Regarding sportfish consumption per month in the last year, 30.6% reported eating 1–3 meals and 21.2% reported eating more than 3 meals. When asked about purchased fish consumption per month, 26.3% reported eating 1–3 meals. The overwhelming majority were not aware of safe-eating sportfish guidelines for Wisconsin (88.3%) or Milwaukee waterbodies (96.6%). ConclusionsRDS is an effective methodology to recruit hard-to-reach populations, such as the Burmese surveyed in this study. High percentages of WCBA eating potentially contaminated sportfish meals, low awareness of consumption advisories, and limited economic resources make the Burmese population more likely to be exposed to contaminants. Health education efforts should be focused in this vulnerable population, particularly among Burmese WCBA.

Stepping Stones or Second Class Donors?: a qualitative analysis of gay, bisexual, and queer men\u2019s perspectives on plasma donation policy in Canada

BackgroundMen who have sex with men (MSM) are not eligible to donate blood or plasma in Canada if they have had sex with another man in the last 3 months. This time-based deferment has reduced since 2013; from an initial lifetime ban, to five-years, one-year, and now three-months. Our previous research revealed that gay, bisexual, queer, and other MSM (GBM) supported making blood donation policies gender-neutral and behaviour-based. In this analysis, we explored the willingness of Canadian GBM to donate plasma, even if they were not eligible to donate blood.MethodsWe conducted in-depth interviews with 39 HIV-negative GBM in Vancouver (n = 15), Toronto (n = 13), and Montreal (n = 11), recruited from a large respondent-driven sampling study called Engage. Men received some basic information on plasma donation prior to answering questions. Transcripts were coded in NVivo following inductive thematic analysis.ResultsMany GBM expressed a general willingness to donate plasma if they became eligible; like with whole blood donation, GBM conveyed a strong desire to help others in need. However, this willingness was complicated by the fact that most participants had limited knowledge of plasma donation and were unsure of its medical importance. Participants’ perspectives on a policy that enabled MSM to donate plasma varied, with some viewing this change as a “stepping stone” to a reformed blood donation policy and others regarding it as insufficient and constructing GBM as “second-class” donors. When discussing plasma, many men reflected on the legacy of blood donor policy-related discrimination. Our data reveal a significant plasma policy disjuncture—a gulf between the critical importance of plasma donation from the perspective of Canada’s blood operators and patients and the feelings of many GBM who understood this form of donation as less important.ConclusionsPlasma donor policies must be considered in relation to MSM blood donation policies to understand how donor eligibility practices are made meaningful by GBM in the context of historical disenfranchisement. Successful establishment of a MSM plasma donor policy will require extensive education, explicit communication of how this new policy contributes to continued/stepwise reform of blood donor policies, and considerable reconciliation with diverse GBM communities.

High prevalence of anal high-risk HPV infection among transwomen: estimates from a Brazilian RDS study.

IntroductionAs the leading sexually transmitted infection worldwide, human papillomavirus (HPV) may disproportionately affect transwomen. We aimed to estimate anal HPV prevalence, especially focusing on high‐risk (hr)‐HPV types and evaluate their associated factors among transwomen living in Rio de Janeiro, Brazil.MethodsTranswomen enrolled in a respondent‐driven sampling (RDS)‐based survey conducted between August 2015 and January 2016 self‐collected anal samples, which were promptly stored at minus 80°C. After DNA extraction, HPV detection and genotyping were performed using the PapilloCheck test. We estimated HPV prevalences and evaluated the correlates of anal hr‐HPV infection using a regression logistic model.ResultsOut of 345 transwomen, 272 (78.8%) were included in this analysis (122 [44.9%] HIV‐positive). No participant had ever received HPV vaccination. Among participants enrolled, 212 (77.9%) were positive for any anal HPV type and 165 (60.7%) for hr‐HPV. Most common hr‐HPV were as follows: HPV16 (17.6%), HPV68 (14.7%), HPV39 (14.3%), HPV56 (12.5%), HPV51 (11.4%) and HPV52 (11.0%). HIV‐positive transwomen had three times the odds of having an hr‐HPV compared to HIV‐negative transwomen. Participants who had a current rectal Neisseria gonorrhoeae infection had 3.7 times the odds of being coinfected with hr‐HPV. Among HIV‐positive transwomen, neither antiretroviral therapy use, undetectable viral load, current and nadir CD4 counts were associated with anal hr‐HPV infection.ConclusionsBrazilian transwomen in our study exhibit some of the highest population‐specific rates of HPV and hr‐HPV. There is an urgent need to elucidate the burden of HPV infection, prevalence of HPV‐related diseases and access to and uptake of HPV vaccination among transwomen, especially from low‐ and middle‐income settings.

Exploring the Association Between Depression and Social and Biobehavioral HIV Risk Factors Among Female Sex Workers in Nelson Mandela Bay Municipality, South Africa.

The aim of this study was to estimate the prevalence of depression among female sex workers (FSW) in an urban coastal city in South Africa, and to explore the relationship between depression and HIV-related social and biobehavioral determinants. A cross-sectional respondent-driven sampling study was conducted with FSW (n = 410), including a sociobehavioral questionnaire, PHQ-9 (Patient Health Questionnaire-9) based assessment of depression, and biological testing for HIV and syphilis. The prevalence of HIV in the sample was 64.1%. The estimated prevalence of depression was 28.8%. Depression was associated with social vulnerability such as living alone [adjusted prevalence ratio 1.82, 95% confidence interval (CI) 1.15-2.90] and food insecurity (aPR 2.19, 95% CI 1.42-3.38). A positive syphilis test result (aPR 1.46, 95% CI 1.02-2.09) and self-reported sexually transmitted disease symptoms (aPR 1.78, 95% CI 1.29-2.46) was associated with depression, but self-reported condom use and HIV status was not. FSW were also less likely to disclose their occupational status to health care providers (aPR 0.61, 95% CI 0.42-0.89) or undergo sexually transmitted infection screening in the last 12 months if they are depressed (aPR 0.64, 95% CI 0.43-0.95). The results demonstrate that the prevalence of depression is high among FSW and that depressive symptoms are associated with social covariates and biobehavioral HIV risk factors.

Reassessing geographic bottlenecks in a respondent-driven sampling based multicity study in Brazil.

This study analyzes the spatial dynamics of drug users' recruitment chains in the context of a respondent-driven sampling (RDS) study in the city of Recife, Brazil. The purpose is to understand the geographic bottlenecks, influenced by social geography, which have been a major challenge for RDS-based studies. Temporo-spatial analysis was used. Sequential maps depicted the dynamics of the recruiting process, considering neighborhood of residence and/or places of drug use. Poisson regression was fitted to model the recruiting rate by neighborhood of residence and/or places of drug use, and the different neighborhoods' demographics. The distance between neighborhood of residence and/or places of drug use and the assessment center was negatively associated with recruitment. There was a positive association between the proportion of the population living in informal settings and the recruiting rate per neighborhood of residence and/or places of drug use. Recruitment chains depend on the social geography and demographics of the population. Studies should incorporate seeds from as many neighborhoods as possible, and more than one assessment center should be utilized.

Risky injection practices and HCV awareness in Chiang Mai Province, Thailand: a respondent-driven sampling study of people who inject drugs

BackgroundPeople who inject drugs (PWID) are the most exposed to hepatitis C virus (HCV). In Thailand, drug use is highly criminalized, and harm reduction services are scarce. This study estimates risky injection practices and assesses the proportion of HCV awareness and screening in the PWID population in Northern Thailand.MethodsWe used respondent-driven sampling (RDS) to recruit PWID in Chiang Mai Province. Social and behavioural data were collected through face-to-face interviews at an addiction treatment facility. Weighted population estimates were calculated to limit biases related to the non-random sampling method. Univariate and multivariate analyses were performed to study factors associated with HCV awareness and screening.ResultsOne hundred seventy-one PWID were recruited between April 2016 and January 2017. Median age was 33 (Interquartile range: 26–40) years, 12.2% were women, and 49.4% belonged to a minority ethnic group. Among participants, 76.8% injected heroin, 20.7% methadone, and 20.7% methamphetamine. We estimate that 22.1% [95% CI: 15.7–28.6] of the population had shared needles in the last 6 months and that 32.0% [95% CI: 23.6–40.4] had shared injection material. Only 26.6% [95% CI: 17.6–35.6] had heard of HCV. Factors independently associated with knowledge of HCV included belonging to a harm reduction organization (adjusted odds ratio (aOR) = 5.5 [95% CI: 2.0–15.3]) and voluntary participation in a drug rehabilitation programme (aOR = 4.3 [95% CI: 1.3–13.9]), while Lahu ethnicity was negatively associated (aOR = 0.3 [95% CI: 0.1–0.9]). We estimate that 5% of the PWID population were screened for HCV; the only factor independently associated with being screened was membership of a harm reduction organization (aOR = 5.7 [95% CI: 1.6–19.9]).ConclusionOur study reveals that the PWID population is poorly informed and rarely screened for HCV, despite widespread risky injection practices. A public health approach aimed at reducing the incidence of HCV should target the PWID population and combine harm reduction measures with information and destigmatization campaigns. Civil society organizations working with PWID are a major asset for the success of such an approach, based on their current positive interventions promoting awareness of and screening for HCV.