Social Capital Moderates the Relationship Between Stigma and Sexual Risk Among Male Sex Workers in the US Northeast

Abstract

Stigma contributes to elevated HIV incidence among male sex workers (MSW). Social capital (i.e., resources accessed through one’s social relationships) may act as a buffer between stigma and sexual risk behaviors and HIV acquisition. Using negative binomial regression, we examined the association between both sex work-related stigma and social capital with respect to number of condomless sex acts among 98 MSW living in the US Northeast. In models adjusted for sociodemographic characteristics, sex work-related stigma was associated with number of condomless sex acts with any non-paying partner (i.e., male and female) (aIRR = 1.25, p < 0.001) and male non-paying partners (aIRR = 1.27, p = 0.09) among individuals with low social capital, not among those with high social capital. Sex work-related stigma was not associated with number of condomless anal sex acts with male paying clients at any level of social capital. Future HIV prevention interventions should consider promoting social capital among MSW.

Introduction

Men who have sex with men in exchange for money (i.e., male sex workers, MSW) are at increased risk for HIV infection. In the United States, HIV prevalence among MSW has been estimated at 19.3%—24-fold greater than among the general adult male population [1]. Moreover, a recent study with men who have sex with men (MSM) in 20 cities of the United States showed that HIV prevalence is significantly higher among MSW in comparison to MSM who do not engage in sex work (29.1% vs. 17.7%, respectively, p < 0.001) [2].

Increased HIV risk among MSW is attributed to behavioral factors, such as condomless anal sex (CAS) and multiple sexual partners [2, 3], interpersonal factors such as experiences of physical, emotional, and sexual violence [4–7], and structural factors, including lack of protective policies for MSW [8]. Additionally, MSW and other MSM may face intersecting stigmas related to their sexual orientation, engagement in sex work, and HIV status, which also contribute to HIV risk [9–14]. Stigma related to sexuality or HIV status may increase condomless sex by fostering engagement in sexual encounters in which condom negotiation is more challenging, such as having sex while drunk or high or in the context of interpersonal relationships with power disparities between partners [14, 15]. Intersecting stigmas may also contribute to adverse mental health outcomes among MSW and MSM, such as depression, anxiety, suicidal ideation and attempts, and substance abuse [13, 16–18], which in turn are associated with increased engagement in HIV risk behaviors [5, 19–21].

Over the past two decades, there has been a pronounced increase in studies examining the role of social capital in health [22]. Though many definitions exist, social capital can be broadly defined as the resources to which individuals and communities have access through their social relationships [22]. In the public health and social sciences literatures, two main theoretical and methodological approaches exist. The communitarian, or cohesion, approach to social capital focuses on aspects of social organization, norms of reciprocity, and trust in others [23–26]. The communitarian approach to social capital involves a cognitive component (i.e. perceived trust in individuals in the community and in the community at large) and a structural component (i.e. participation in civic organizations and engagement in public affairs in the community) [25–27]. On the other hand, the network, or relational, approach to social capital emphasizes the actual and potential material and symbolic resources obtained through one’s social ties [28–30], as measured through the amount of instrumental, financial, and emotional support accessed via one’s social networks [22, 25, 29].

To date, the communitarian approach to conceptualizing social capital has been largely predominant in the public health literature [22, 31], and there is ample evidence linking it to positive health and social outcomes, including with respect to HIV prevention and care. Ecological studies with a variety of populations in the United States have linked higher communitarian social capital to safer sexual behaviors, early HIV detection, and improved engagement in HIV care [32–35]. Moreover, a cross-sectional study with people living with HIV in five different countries indicated that higher levels of communitarian social capital were associated with better self-rated physical and mental health [36].

Research with female sex workers (FSW) shows that communitarian social capital is associated with increased condom use and lower prevalence of sexually transmitted infections (STIs) [37, 38]. However, evidence of the relationship between communitarian social capital and HIV-related outcomes among MSW and other MSM is mixed. Among MSW in Brazil, communitarian social capital was not significantly associated with safer sexual behaviors [39], but a study with MSM in Swaziland showed a positive association between communitarian social capital and HIV testing [40].

Studies have demonstrated a positive association between the relational dimension of social capital and health-related outcomes, including self-rated health, psychological distress, hypertension and obesity [26, 41–44]. However, to our knowledge, there are no published studies investigating the role of relational social capital with respect to HIV-related outcomes. Given that relational social capital emphasizes resources individuals, rather than communities, have access to, exploring the role of this dimension of social capital in shaping interpersonal behaviors, such as condomless sex, may be conceptually appropriate.

Though research on social capital and health has primarily investigated the main effect of social capital on health outcomes, it has also been hypothesized that social capital may moderate the relationship between psychosocial stressors and health outcomes [45]. The moderation effect, or stress-buffering, hypothesis posits that the beneficial effects of social relationships on health are seen only among individuals and communities under high levels of psychosocial stress [45, 46]. Recent studies have provided support for the stress-buffering role of social capital. For example, Walsh et al. [47] showed the communitarian dimension of social capital to moderate the association between discrimination and substance use among adolescents in Israel. Moreover, a cross-sectional study with mother–children dyads in the United States showed relational social capital to moderate the effect of parental stress on emotional overeating among their children [48]. Importantly, to our knowledge, there are no published studies evaluating social capital as a moderator of the relationship between psychosocial stressors, such as stigma, and sexual risk behaviors.

To address the noted gaps in the literature, we set out to examine the relationship between experiencing sex work-related stigma and engaging in condomless anal or vaginal sex (CAVS) and further assess if relational social capital moderates this relationship. We tested the hypotheses that (1) sex work-related stigma is associated with higher number of CAVS acts with paying and non-paying partners; (2) higher level of relational social capital is associated with lower number of CAVS acts with paying and non-paying partners (main-effect hypothesis); and (3) relational social capital moderates the association between sex work-related stigma and CAVS with paying and non-paying partners (stress-buffering hypothesis).

Methods

Study Design and Recruitment

Between 2014 and 2016, we recruited cisgender MSW living in Massachusetts and Rhode Island to participate in a study examining their social, sexual, and drug networks, sociodemographics, and related psychosocial measures. We collected data from 100 participants, but two individuals did not provide information about their social networks and were excluded from further analyses. Participants were recruited online and at community-based organizations and were eligible for participation if they met the following criteria: (i) 18 years of age or older, (ii) biologically male at birth and identified as male at time of enrollment (i.e. cisgender man), (iii) self-reported MSM, (iv) exchanged oral or anal sex for money with at least three men in the past month, and (v) English-speaking.

Participants met with trained interviewers at private locations, where they completed quantitative assessments and were offered HIV and STI testing. Survey questions related to sexual behaviors and stigma were collected using audio computer-assisted self-interviewing (ACASI), while information related to sociodemographic characteristics and social networks were administered by interviewers.

All participants provided written informed consent. Study procedures and materials were approved by the Institutional Review Board at Fenway Health.

Measures

Sexual Risk Behaviors

Participants were asked about the number of condomless sex acts with non-paying female sex partners (“In the past month, how many times have you had anal or vaginal sex without a condom with non-paying female partners?”), non-paying male partners (“In the past month, how many times have you had anal [receptive or insertive] sex without a condom with male non-paying sex partners?”), and paying male sex partners in the past month (“In the past month, how many time have you had anal [receptive or insertive] sex without a condom with male clients?”). These questions were adapted from our previous work with MSM and other sexual and gender minorities [10, 49, 50], and other studies have utilized similar approaches to measuring sexual risk behaviors among MSW [39]. All participants were given definitions of receptive anal sex, insertive anal sex, vaginal sex, non-paying partners (i.e. “a male or female sexual partner who does not pay you to have sex with them”), and clients (i.e. “a male or female sexual partner who pays you money to have sex with them”) before answering questions about sexual behaviors. These data were collected using ACASI to facilitate accurate reporting of sensitive sexual behavior [51, 52].

For this analysis, our final measures of sexual risk behavior were (1) number of CAVS acts with any non-paying partner (i.e., male and female), (2) number of CAS acts with male non-paying partners, and (3) number of CAS acts with male paying partners (i.e., clients).

Sex Work‑Related Stigma

We measured sex work-related stigma in the past month with a 6-item scale which assesses enacted, perceived, and internalized dimensions of stigma related to sex work. This scale has been previously used in a study with MSW in Vietnam (Cronbach’s α = 0.76) [16]. Sample items included: “in the past month, how often have you been made fun of or called names for engaging in sex work?”, “in the past month, how often have you felt that people would dislike you if they know that you are a sex worker?”, and “in the past month, how often have people’s comments and actions toward sex workers affected your emotional and mental wellbeing?”. Participants rated their responses on a four-point Likert scale ranging from “(0) never” to “(3) many times”, leading to a final score with possible values ranging from 0 to 18, higher values indicating higher levels of sex work-related stigma (Cronbach’s α = 0.73).

Social Capital

We measured the relational dimension of social capital using an egocentric network approach that considers both the size of social networks and the material and social resources obtained through these ties [53]. First, we compiled participants’ network inventory by assessing first names and initials of all individuals participants had in their social, sexual and drug use networks, including family members, friends, peers, etc. (i.e., name-generating questions). Then, we examined access to seven types of material and social resources (instrumental, financial, and emotional) in the past month via their interpersonal relationships (i.e., name interpreters) [54]. Name-interpreter questions were adapted from Latkin et al. [55] and included, “During the last month, who did you entrust with your money to get groceries, pay your bills or run errands for you?” and “During the last month, who did you talk to about things that were personal and private or who did you get advice from?”. Our final social capital measure was the number of unique individuals who had provided the participant with instrumental, financial, or emotional support in the past month [53].

Covariates

We assessed sociodemographic characteristics such as age, race/ethnicity, income, educational attainment, employment (other than sex work), sexual orientation, and current relationship status. We also determined venue for sex work based on where participants had met clients in the past 6 months. Responses were classified as “offline venues only”, “offline venues only”, and “both”.

Data Analysis

We present frequencies and descriptive statistics (mean, standard deviation [SD]) of sociodemographic characteristics and measures of sex work-related stigma, social capital, and sexual risk behaviors. Multivariable negative binomial regression models were fit to test the associations between both sex work-related stigma and social capital (independent variables) with respect to number of CAVS acts reported (over-dispersed dependent count variable). We fit three models, each with one of the following as the dependent variable: number of CAVS acts with any non-paying partner, number of CAS acts with male non-paying partners, and number of CAS acts with male clients. Interaction terms were added to regression models to assess whether the relationship between sex work-related stigma and number of CAVS was moderated by levels of social capital. All final models were adjusted for age (continuous), race/ethnicity (white vs. non-white), venue for sex work (offline venues only vs. meeting clients online), income, and educational attainment (high school education or less vs. more than high school). Pairwise deletion of missing values resulted in exclusion of eight individuals from the analyses that modeled number of CAVS acts with any non-paying partner (final N = 90), nine individuals from models assessing number of CAS acts with male non-paying partners (final N = 89), and eight individuals from models examining number of CAS acts with male clients (final N = 90). Statistical significance of incidence rate ratios (IRR) was set at α = 0.05. Analyses were run in IBM SPSS Statistics v. 24.

Results

Sample characteristics are described in Table 1. In brief, participants’ age ranged from 19 to 61 years (M = 33.5, SD = 11.5). Our sample was diverse in race/ethnicity: 39% were White, 33% Black, 19% Latino, 3% Native American/ Alaska Native, 1% Asian, and 4% were multiracial. About half (47%) identified as bisexual, 37% as gay, and 12% as straight. The majority of participants were single (68%), 17% were in a relationship with another man, and 13% were in a relationship with a woman. On average, participants had been doing sex work for 9.7 years (SD = 9.4), ranging from less than a year to 44 years. Regarding the venues where participants met their clients, 53% only solicited in offline venues, 32% only on the internet, and 16% in both environments. Most participants had only completed high school or less (60%) and about half (43%) reported an annual household income of $12,000 or less. Besides sex work, 63% of the participants were not employed, 21% were employed at least part-time, and 12% were currently students.

Table 1.

Characteristics of our sample (N = 98)

Age (years), mean (SD)	33.5 (11.5)
Sexual orientation, n (%)
Bisexual	46 (47%)
Gay or homosexual	36 (37%)
Straight	12 (12%)
Don’t know/unsure	3 (3%)
Race/ethnicity, n (%)
White	38 (39%)
Black	32 (33%)
Latino/Hispanic	19 (19%)
Multiracial	4 (4%)
American Indian/Alaska Native	3 (3%)
Asian	1 (1%)
Other	1 (1%)
Relationship status, n (%)
Single	67 (68%)
Relationship with man	17 (17%)
Relationship with woman	13 (13%)
Employment not related to sex work, n (%)
Full-time	5 (5%)
Part-time	16 (16%)
Student	12 (12%)
Education attainment, n (%)
Less than high school	15 (15%)
High school or GED	44 (45%)
Some college	26 (27%)
Completed college or higher	13 (13%)
Annual household income, n (%)
$12,000 or less	42 (43%)
$12,000–$24,000	17 (17%)
$24,000–$60,000	29 (30%)
More than $60,000	6 (6%)
Sex work-related stigma score, Mean (SD)	3.6 (3.5)
Social capital, Mean (SD)	4.2 (2.7)
Number of CAVS or CAS acts reported, Mean (SD)
CAVS with any non-paying partner	6.9 (13.7)
CAS with male non-paying partners	2.8 (7.3)
CAS with male clients	2.2 (4.6)

Sex Work Stigma, Social Capital and Sexual Risk

Sex work-related stigma scale scores ranged from 0 to 14 in our sample (M = 3.6, SD = 3.5). The mean social capital scale score was 4.2 (SD = 2.7, range = 0–15), indicating that, on average, participants had obtained some kind of instrumental, financial, or emotional support from 4.2 individuals in the past month (Table 1). In the past month, most participants (67%) reported having had CAVS with any non-paying sexual partner (mean [SD] number of acts = 6.9 [13.7]); 42% reported CAS with a male non-paying partner (mean [SD] number of acts = 2.8 [7.3]); and about half (47%) reported CAS with a male client (mean [SD] number of acts = 2.2 [4.6]).

In unadjusted analyses (Table 2), sex work-related stigma was positively associated with number of CAVS acts with any non-paying partner (IRR = 1.15 [1.04–1.27], p = 0.007); however, it was not associated with CAS with male non-paying partners or male clients. Additionally, social capital was not significantly associated with CAVS with any partner type (paying or non-paying). Adjusting for age, race/ethnicity, sex work venue, income, and educational attainment did not meaningfully change the associations (Table 2).

Table 2.

Bivariate and multivariable negative binomial regression models

	Bivariate analysis			Multivariable modela			Interactionab
	IRR	95% CI	p-value	aIRR	95% CI	p-value	aIRR	95% CI	p-value
Number of CAVS acts with any non-paying partner (N = 89)
Sex work-related stigma	1.15	(1.04–1.27)	0.007	1.18	(1.06–1.32)	0.003	1.68	(1.16–2.42)	0.006
Social capital	1.01	(0.9–1.12)	0.92	1.07	(0.93–1.23)	0.35	1.25	(0.84–1.86)	0.26
Interaction	–	–	–	–	–	–	0.72	(0.54–0.98)	0.03
Number of CAS acts with male non-paying partners (N = 90)
Sex work-related stigma	1.11	(0.96–1.27)	0.16	1.18	(0.98–1.43)	0.09	1.79	(1.02–3.16)	0.04
Social capital	1.08	(0.93–1.25)	0.32	1.22	(0.97–1.54)	0.09	1.81	(0.94–3.51)	0.08
Interaction	–	–	–	–	–	–	0.57	(0.35–0.93)	0.02
Number of CAS acts with male clients (N = 89)
Sex work-related stigma	1.06	(0.95–1.19)	0.32	1.05	(0.95–1.16)	0.37	1.18	(0.82–1.69)	0.38
Social capital	1.13	(0.94–1.35)	0.18	1.09	(0.93–1.29)	0.28	1.26	(0.82–1.95)	0.29
Interaction	–	–	–	–	–	–	1.05	(0.72–1.52)	0.82

^aAll multivariable models adjusted for age, race/ethnicity, household income, educational attainment, and venue for sex work

^bModels with interaction terms used standardized values of sex work-related stigma and social capital

Significant p-values are given in bold (p < 0.05)

The associations between sex work-related stigma and number of CAVS acts with any non-paying partner and number of CAS acts with male non-paying partners were significantly modified by social capital (p = 0.03 and p = 0.02, respectively) (Table 2). As depicted in Fig. 1, in analyses stratified by low and high social capital (i.e., mediansplit = 4), sex work-related stigma was positively associated with number of CAVS acts with any non-paying partner among individuals with low social capital (aIRR = 1.25 [1.11–1.41], p < 0.001), but not among those with high social capital (p = 0.47). Similarly, sex work-related stigma was marginally positively associated with number of CAS acts with male non-paying partners among individuals with low social capital (aIRR = 1.27 [0.96–1.69], p = 0.09), but not among those with high social capital (p = 0.71). Social capital did not modify the non-significant association between sex work-related stigma and CAS acts with male clients.

Fig. 1.

Relationship between sex work-related stigma and sexual risk by different levels of social capital. a Effect modification of social capital in the association between sex work-related stigma and estimated number of CAVS acts with any non-paying partner. b Effect modification of social capital in the association between sex work-related stigma and estimated number of CAS acts with male non-paying partners

Discussion

To our knowledge, this is the first study directly examining the impact of relational social capital on sexual risk behaviors among MSW. We show that relational social capital moderated the association between sex work-related stigma and both CAVS with any non-paying partner and CAS with male non-paying partners. This finding is aligned with studies showing that other forms of social capital (i.e., communitarian) are associated with safer sexual behaviors and lower case rates of HIV and STIs among adolescents and adults in the United States [33, 34] and FSW in other countries [37, 38, 56]. A recent systematic review on the health outcomes of HIV-related stigma has called for more studies to examine factors that could mitigate the negative effect of stigma on physical and mental health [57]. Our study responds to this call and adds to the limited literature examining HIV-related impacts of social capital. Our findings suggest that social capital may be an important interpersonal mechanism that could contribute to prevent HIV transmission among MSW. Moreover, by demonstrating that relational social capital moderates the association between sex work-related stigma—a psychosocial stressor [58]—and sexual risk behaviors, our study lends support to the stress-buffering role of social capital [45, 46].

Contrary to our hypothesis, however, in our study there was no significant relationship between sex work-related stigma, social capital, and CAS with male clients. Our finding thus contrasts with the study by Lippman et al. with FSW in Brazil, which found communitarian social capital to promote condom use with clients but not with non-paying partners [59]. There are several possible explanations for this discrepancy. First, in our study, participants reported smaller average number of CAS acts with male clients (and lower variance) in comparison with reported number of CAVS acts with any non-paying partners and number of CAS acts with male non-paying partners, which could have limited our ability to show statistically significant relationships. Second, previous studies have indicated that financial need and monetary incentives may be important drivers of condomless sex with clients [3, 60, 61]. Therefore, it is possible that the buffering effect of social capital in the association between sex work-related stigma and CAVS may be limited in the face of greater structural barriers to condom use, such as financial need. This explanation is aligned with the proposition that the influence of social capital on health is dependent on other sources of human capital, such as income, education, and social class [62]. Indeed, Bourdieu’s theory of relational social capital emphasizes the complex and dynamic interplay between different forms of capital, such as economic resources, educational attainment, and social capital [28, 29, 31]. Future research should examine the relationships between access to different forms of capital, including economic and social capital, with respect to sexual risk behaviors among MSW. Third, it is possible that the communitarian and relational dimensions of social capital may have different effects on sexual risk behaviors among sex workers. Previous studies have proposed that, despite being conceptually related, communitarian and relational social capital may be two distinct theoretical constructs with different influences on mental and physical health [26, 29]. As pointed out by previous research [32, 57], little is known about the mechanisms that link social capital, stigma, and sexual behaviors, a gap which we believe should be addressed by future research. These studies should consider the different types of sexual relationships (e.g. paying vs. non-paying) and dimensions of social capital (i.e. communitarian and relational) in the context of sexual risk behaviors and sex work-related stigma.

Despite the lack of influence of social capital on CAS with male clients, the buffering effect of social capital on CAVS with non-paying partners and CAS with male non-paying partners is a relevant finding regarding HIV risk among MSW. Previous studies indicate that MSW may have different risk-taking practices with paying and non-paying partners [3] and that CAVS may be more common with non-paying than paying partners [2, 63, 64]. Among the broader population of MSM, more frequent CAS with primary partners may contribute to higher risk of HIV transmission risks in comparison to casual partners [65, 66]. Similarly, studies with FSW indicate that higher prevalence of condomless sex with non-paying partners may lead to greater HIV risk within non-paying sexual relationships in comparison with paying clients [67]. Taken together, the evidence suggests that CAVS with non-paying sexual partners may play an important role in the HIV transmission dynamics among MSW. Therefore, identifying resources that could decrease engagement in sexual risk behaviors with non-paying sexual partners among MSW, such as social capital, may contribute to HIV prevention efforts among this population. Future research should investigate what components of relational social capital (i.e. specific instrumental, financial, or emotional resources obtained through one’s social relationships) most effectively promote condom use in MSW’s non-transactional sexual relationships. Identifying particularly promising components of relational social capital can then inform multipronged approaches to HIV prevention that include the promotion of knowledge and skills for sharing specific instrumental, financial, or emotional resources within social networks of MSW.

In our study, most participants reported being straight or bisexual (12% and 47%, respectively). Moreover, a substantial proportion of MSW in our sample were engaging in sex with both men and women, and condomless sex with their female partners was common. Indeed, prior research suggests that while most paying partners of MSW are men [68, 69], bisexual behavior is common among MSW and condom use with female partners is often inconsistent [64, 70–74]. Therefore, that social capital may buffer the association between sex-work related stigma and condomless sex with male and female non-paying partners is of relevance for HIV transmission among both male and female populations. Future studies should investigate potential differences in the relationships between stigma and condom use with male and female non-paying partners and the role of social capital in sexual interactions with partners of different genders.

Previous research indicates that MSM-related stigma may lead to difficult sexual situations and limited opportunities for effective condom negotiation, which in turn may facilitate condomless sex among MSM. For example, a cross-sectional study with MSM of color in three cities in the US showed that the association between MSM-related stigma and CAS was partially mediated by engagement in difficult sexual situations (i.e. situations in which condom use is difficult, such as the existence of power inequalities between sexual partners and alcohol or drug use before or during sex) [14]. Similarly, a longitudinal study with MSM in China also showed difficult sexual situations to mediate the association between MSM-related stigma and CAS [15]. Thus, one possible mechanism through which social capital may mitigate the effect of sex work-related stigma on condomless sex is by providing MSW with instrumental, financial, or emotional resources to prevent difficult sexual situations or promote condom negotiation skills with non-paying partners.

Other possible mediators of the relationship between stigma and sexual risk include mental health factors. However, despite strong evidence showing associations between MSM- and sex work-related stigma and adverse mental health outcomes [13, 16–18, 57, 75, 76] and between poor mental health and sexual risk behaviors [5, 13, 19–21, 77], the mediating role of mental health symptoms in the relationship between stigma and sexual risk remains unclear. For example, some studies have shown anxiety symptoms [15] and low self-esteem [78] to mediate the association between HIV- and MSM-related stigma and CAS among MSM. Conversely, Hatzenbuehler et al. demonstrated that depression and anxiety symptoms did not mediate the relationship between HIV-related stigma and sexual risk behaviors [10]. Future research should examine potential mediators of the relationship between stigma, social capital, and sexual risk behaviors, such as anxiety and depression symptoms, substance use, difficult sexual situations, and condom selfefficacy. Such studies will contribute to the understanding of the role of sex work-related stigma and relational social capital with respect to condom use in paying and non-paying sexual partnerships, and may ultimately enhance interventions to promote relational social capital as part of HIV risk reduction strategies.

Our study has several limitations. First, our cross-sectional design limits our ability to draw causal inferences. However, our hypotheses were driven by a robust body of literature, including longitudinal and experimental studies with FSW [37], showing social capital to be a predictor, not an outcome, of sexual behaviors; we believe these previous studies provide an empirical framework for the interpretation of the directionality of our findings. Second, even though our sample was diverse in race/ethnicity, sexual orientation, and venue frequented for sex work, our non-probability sampling based in the US Northeast limits the generalizability of our findings to other populations of MSW. Third, we only examined sex work-related stigma and did not investigate the impact of other forms of stigma such as homophobia and HIV-related stigma on sexual behaviors among MSW. Finally, though we employed ACASI to collect potentially sensitive data (i.e. sexual behaviors and experiences and perceptions of sex work-related stigma), our study relies on self-reported data, which are subject to social desirability and recall biases.

Despite these limitations, we present an important contribution to the scarce literature on stigma and group-level coping resources among MSW in the United States and indicate that social capital may contribute to HIV prevention efforts among this population. A systematic review of studies with FSW in low- and middle-income countries showed that interventions based on community empowerment and promotion of communitarian forms of social capital are effective to promote condom use and prevent transmission of HIV and other STIs [37]. Moreover, a cluster randomized trial has shown that community-based interventions containing HIV prevention and microfinance components are able to improve social capital levels in rural communities in South Africa [79]. To date, no published interventions have aimed to promote relational forms of social capital to support HIV prevention efforts among MSW. Future interventions should not only encourage the development of social ties between MSW but also the exchange of actual material and social resources through these social relationships.