Thespina J. Yamanis

An empirical analysis of the impact of recruitment patterns on RDS estimates among a socially ordered population of female sex workers in China

Respondent-driven sampling (RDS) is a method for recruiting “hidden” populations through a network-based, chain and peer referral process. RDS recruits hidden populations more effectively than other sampling methods and promises to generate unbiased estimates of their characteristics. RDS’s faithful representation of hidden populations relies on the validity of core assumptions regarding the unobserved referral process. With empirical recruitment data from an RDS study of female sex workers (FSWs) in Shanghai, we assess the RDS assumption that participants recruit nonpreferentially from among their network alters. We also present a bootstrap method for constructing the confidence intervals around RDS estimates. This approach uniquely incorporates real-world features of the population under study (e.g., the sample’s observed branching structure). We then extend this approach to approximate the distribution of RDS estimates under various peer recruitment scenarios consistent with the data as a means to quantify the impact of recruitment bias and of rejection bias on the RDS estimates. We find that the hierarchical social organization of FSWs leads to recruitment biases by constraining RDS recruitment across social classes and introducing bias in the RDS estimates.

Intimate Partner Violence and the Association With HIV Risk Behaviors Among Young Men in Dar es Salaam, Tanzania

There is growing evidence of the association between gender-based violence and HIV from the perspective and experiences of women. The purpose of this study is to examine these associations from the perspective of young men living in Dar es Salaam, Tanzania. A community-based sample of 951 men were interviewed, of whom 360 had sex in the past 6 months and were included in these analyses. Almost a third of the men (29.2%) reported that they had been physically violent at least once with an intimate partner. Men who reported more lifetime sexual partners (OR = 8.75; 95% CI = 2.65, 28.92), experienced physical violence as a child at home (OR = 1.73; 95% CI = 1.09, 2.76), and were more educated (OR = 1.91; 95% CI = 1.18, 3.11) were significantly more likely to report perpetrating violence. These associations persisted after adjusting for other variables. These data from the perspective of young men reinforce earlier findings from women that HIV risk and violence are occurring together in relationships of young adults. Interventions are needed to identify men at high risk for HIV and engage them in interventions that are designed to change norms and behaviors related to power and control with their sexual partners.

Evidence of social network influence on multiple HIV risk behaviors and normative beliefs among young Tanzanian men

Research on network-level influences on HIV risk behaviors among young men in sub-Saharan Africa is severely lacking. One significant gap in the literature that may provide direction for future research with this population is understanding the degree to which various HIV risk behaviors and normative beliefs cluster within mens social networks. Such research may help us understand which HIV-related norms and behaviors have the greatest potential to be changed through social influence. Additionally, few network-based studies have described the structure of social networks of young men in sub-Saharan Africa. Understanding the structure of mens peer networks may motivate future research examining the ways in which network structures shape the spread of information, adoption of norms, and diffusion of behaviors. We contribute to filling these gaps by using social network analysis and multilevel modeling to describe a unique dataset of mostly young men (n = 1249 men and 242 women) nested within 59 urban social networks in Dar es Salaam, Tanzania. We examine the means, ranges, and clustering of mens HIV-related normative beliefs and behaviors. Networks in this urban setting varied substantially in both composition and structure and a large proportion of men engaged in risky behaviors including inconsistent condom use, sexual partner concurrency, and intimate partner violence perpetration. We found significant clustering of normative beliefs and risk behaviors within these mens social networks. Specifically, network membership explained between 5.78 and 7.17% of variance in mens normative beliefs and between 1.93 and 15.79% of variance in risk behaviors. Our results suggest that social networks are important socialization sites for young men and may influence the adoption of norms and behaviors. We conclude by calling for more research on mens social networks in Sub-Saharan Africa and map out several areas of future inquiry.

Vijana Vijiweni II: a cluster-randomized trial to evaluate the efficacy of a microfinance and peer health leadership intervention for HIV and intimate partner violence prevention among social networks of young men in Dar es Salaam

BackgroundIntimate partner violence (IPV) and sexually transmitted infections (STIs), including HIV, remain important public health problems with devastating health effects for men and women in sub-Saharan Africa. There have been calls to engage men in prevention efforts, however, we lack effective approaches to reach and engage them. Social network approaches have demonstrated effective and sustained outcomes on changing risk behaviors in the U.S. Our team has identified and engaged naturally occurring social networks comprised mostly of young men in Dar es Salaam in an intervention designed to jointly reduce STI incidence and the perpetration of IPV. These stable networks are locally referred to as “camps.” In a pilot study we demonstrated the feasibility and acceptability of a combined microfinance and peer health leadership intervention within these camp-based peer networks.Methods designWe are implementing a cluster-randomized trial to evaluate the efficacy of an intervention combining microfinance with health leadership training in 60 camps in Dar es Salaam, Tanzania. Half of the camps have been randomized to the intervention arm, and half to a control arm. The camps in the intervention arm will receive a combined microfinance and health leadership intervention for a period of two years. The camps in the control arm will receive a delayed intervention. We have enrolled 1,258 men across the 60 study camps. Behavioral surveys will be conducted at baseline, 12-months post intervention launch and 30-month post intervention launch and biological samples will be drawn to test for Neisseria gonorrhea (NG), Chlamydia trachomatis (CT), and Trichomonas vaginalis (TV) at baseline and 30-months. The primary endpoints for assessing intervention impact are IPV perpetration and STI incidence.DiscussionThis is the first cluster-randomized trial targeting social networks of men in sub-Saharan Africa that jointly addresses HIV and IPV perpetration and has both biological and behavioral endpoints. Effective approaches to engage men in HIV and IPV prevention are needed in low resource, high prevalence settings like Tanzania. If we determine that this approach is effective, we will examine how to adapt and scale up this approach to other urban, sub-Saharan African settings.Trial registrationClinical Trials.gov: NCT01865383. Registration date: May 24, 2013.

Fears and Misperceptions of the Ebola Response System during the 2014-2015 Outbreak in Sierra Leone

Background Future infectious disease epidemics are likely to disproportionately affect countries with weak health systems, exacerbating global vulnerability. To decrease the severity of epidemics in these settings, lessons can be drawn from the Ebola outbreak in West Africa. There is a dearth of literature on public perceptions of the public health response system that required citizens to report and treat Ebola cases. Epidemiological reports suggested that there were delays in diagnosis and treatment. The purpose of our study was to explore the barriers preventing Sierra Leoneans from trusting and using the Ebola response system during the height of the outbreak. Methods Using an experienced ethnographer, we conducted 30 semi-structured in-depth interviews in public spaces in Ebola-affected areas. Participants were at least age 18, spoke Krio, and reported no contact in the recent 21 days with an Ebola-infected person. We used inductive coding and noted emergent themes. Findings Most participants feared that calling the national hotline for someone they believed had Ebola would result in that person’s death. Many stated that if they developed a fever they would assume it was not Ebola and self-medicate. Some thought the chlorine sprayed by ambulance workers was toxic. Although most knew there was a laboratory test for Ebola, some erroneously assumed the ubiquitous thermometers were the test and most did not understand the need to re-test in the presence of Ebola symptoms. Conclusion Fears and misperceptions, related to lack of trust in the response system, may have delayed care-seeking during the Ebola outbreak in Sierra Leone. Protocols for future outbreak responses should incorporate dynamic, qualitative research to understand and address people’s perceptions. Strategies that enhance trust in the response system, such as community mobilization, may be particularly effective.

Perpetration and victimization of intimate partner violence among young men and women in Dar es Salaam Tanzania.

We describe and compare the baseline rates of victimization and perpetration of three forms of intimate partner violence (IPV)—psychological, physical, and sexual—among sexually active men (n = 1,113) and women (n = 226) enrolled in an ongoing cluster-randomized HIV and gender-based violence prevention trial in Dar es Salaam, Tanzania. IPV was measured using a modified version of the World Health Organization Violence Against Women instrument. We assess the degree to which men and women report overlapping forms of IPV victimization and perpetration. Sociodemographic and other factors associated with increased risk of victimization and perpetration of IPV are examined. Within the last 12 months, 34.8% of men and 35.8% of women reported any form of IPV victimization. Men were more likely than women to report perpetrating IPV (27.6% vs. 14.6%, respectively). We also found high rates of co-occurrence of IPV victimization and perpetration with 69.7% of male perpetrators and 81.8% of female perpetrators also reporting victimization during the last year. Among men, having ever consumed alcohol and experiencing childhood violence were associated with increased risk of most forms of IPV. Younger women were more likely to report perpetrating IPV than older women. We found evidence of gender symmetry with regard to most forms of IPV victimization, but men reported higher rates of IPV perpetration than women. Given the substantial overlap between victimization and perpetration reported, our findings suggest that IPV may be bidirectional within relationships in this setting and warrant further investigation. Implications for interventions are discussed.

Leveraging strong social ties among young men in Dar es Salaam: A pilot intervention of microfinance and peer leadership for HIV and gender-based violence prevention

ABSTRACT Gender inequality is at the core of the HIV patterns that are evident in sub-Saharan Africa. Gender-based violence (GBV) and lack of economic opportunity are important structural determinants of HIV risk. We piloted a microfinance and health promotion intervention among social networks of primarily young men in Dar es Salaam. Twenty-two individuals participated in the microfinance component and 30 peer leaders were recruited and trained in the peer health leadership component. We collected and analysed observational data from trainings, monitoring data on loan repayment, and reports of peer conversations to assess the feasibility and acceptability of the intervention. Eighteen of the loan recipients (82%) paid back their loans, and of these 15 (83%) received a second, larger loan. Among the loan defaulters, one died, one had chronic health problems, and two disappeared, one of whom was imprisoned for theft. The majority of conversations reported by peer health leaders focused on condoms, sexual partner selection, and HIV testing. Few peer leaders reported conversations about GBV. We demonstrated the feasibility and acceptability of this innovative HIV and GBV prevention intervention. The lessons learned from this pilot have informed the implementation of a cluster-randomised trial of the microfinance and peer health leadership intervention.

“He Told Me to Check My Health”: A Qualitative Exploration of Social Network Influence on Men’s HIV Testing Behavior and HIV Self-Testing Willingness in Tanzania:

Men continue to test for HIV at a low rate in sub-Saharan Africa. Recent quantitative evidence from sub-Saharan Africa indicates that encouragement to test for HIV from men’s network members is associated with higher previous HIV testing and HIV self-testing (HIVST) willingness. Leveraging this positive network influence to promote HIVST among men is a promising strategy that could increase HIV testing. This study investigated the reasons and strategies men used to encourage their peers to test for HIV and the outcomes in order to inform the development of a social network-based HIVST intervention for men called STEP (Self-Testing Education and Promotion). Twenty-three men from networks locally referred to as “camps” were interviewed to explore reasons for encouraging HIV testing, strategies to encourage HIV testing, and outcomes of HIV testing encouragement. Reasons men reported for encouraging their peers to test for HIV included awareness of their peers’ risky sexual behavior, knowing an HIV-positive peer, and having HIV testing experience. Strategies for encouraging testing included engaging in formal and informal conversations and accompanying friends to the clinic. Encouragement outcomes included HIV testing for some men while others remained untested due to lack of privacy in the clinic and fear of HIV stigma. Willingness to self-test for HIV and an interest to educate peers about HIVST were other outcomes of HIV testing encouragement. These findings underscore the potential of leveraging men’s existing HIV testing encouragement strategies to promote HIVST among their peers.

Promoting Pre-Exposure Prophylaxis to Prevent HIV Infections Among Sexual and Gender Minority Hispanics/Latinxs

Sexual and gender minority Hispanics/Latinxs (henceforth: Latinxs) continue to be disproportionately impacted by HIV/AIDS in the U.S. Pre-exposure prophylaxis (PrEP) is a biomedical prevention approach which holds significant promise for at risk and vulnerable populations. We discuss barriers and facilitators to uptake of PrEP among sexual and gender minority Latinxs living in the U.S. through an ecosocial lens that takes into account structural, community, and individual contexts. The impact of immigration status on PrEP uptake emerges as a major and recurrent theme that must be understood and addressed by HIV prevention programs aiming to promote an inclusive strategy for sexual and gender minority Latinxs living in the U.S.

Enhanced immigration enforcement in the USA and the transnational continuity of HIV care for Latin American immigrants in deportation proceedings

In our work as clinicians, researchers, and immigrant rights advocates, we have noted increased anxiety about the possibility of deportation and disruptions in care among immigrants with HIV. Before the 2016 US elections, patients rarely asked about HIV treatment in their home countries. However, since the increase in anti-immigrant rhetoric and arrests by US Immigration and Customs Enforcement, patients have voiced concerns about the availability of HIV treatment in their home countries much more frequently. Although antiretroviral therapy is available throughout Latin America, access depends on economic, social, and political circumstances. Maintaining uninterrupted continuity of care among immigrants held in detention or deported to their home countries is challenging. In this Viewpoint, we identify periods of particular vulnerability for immigrants during deportation proceedings, from initial detention to deposition in their country of origin. We discuss the effect of enhanced immigration enforcement on the health and wellbeing of HIV-infected immigrants, and on public health. Finally, we also discuss recommendations for clinicians, immigration authorities, and public health institutions in the USA and in receiving countries.