El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Sexual communication with partners informs risk assessment and sexual practices. We evaluated participant, partner, and network factors associated with communication about condom use and HIV serostatus and explored their relationships with condomless anal intercourse (CAI) among 446 men who have sex with men (MSM) and 122 transgender women (TW) in Lima, Peru. Generalized estimating equations assessed contextual influences on communication and practices with recent sexual partners. More frequent HIV communication was reported by MSM who: identified as heterosexual, compared to bisexual or gay; characterized partnerships as stable, compared to casual, anonymous, or commercial; or discussed HIV/STIs with close social contacts (p < 0.05). TW in concurrent partnerships discussed condom use more frequently than those in monogamous relationships (p < 0.05). Condom use discussions and alcohol use among MSM were associated with CAI (p < 0.05). Findings highlight complexity in sexual decision-making and call for further study of conversation content and practices to inform HIV prevention messaging. / National Institutes of Health / Revisión por pares

Men who have sex with men continue to be at highest risk of HIV infection, with Black and Latino men who have sex with men [BLMSM] disproportionately at risk. The impact of alcohol consumption on condomless anal intercourse [CAI] is compounded for BLMSM by unique risk factors like internalized homophobia and racial stigma, reinforcing barriers to treatment. The traditional formats of existing HIV interventions fail to address heightened confidentiality concerns of BLMSM and few target both CAI and alcohol use. Existing interventions may be modified with mobile health [mhealth] technologies to improve outcomes for BLMSM. The current study examined the feasibility and acceptability of a novel mhealth intervention to reduce heavy drinking episodes [HDE], reduce CAI, and increase intentions to use pre-exposure prophylaxis medication [PrEP]. METHODS: Enrollment criteria included (1) Black and/or Latino man, (2) at least one episode of CAI with another man in the past six months, (3) at least one HDE in the past month and (4) no current PrEP use. Twelve participants completed a brief videoconferencing session then four weeks of interactive mobile messages. Outcome assessment was completed 8-weeks post-baseline. To assess feasibility and acceptability (primary outcomes), message response rates, ratings of intervention satisfaction (Client Satisfaction Questionnaire-8, CSQ), and ratings from a 10-item acceptability measure were used. RESULTS: Message response rates (M= 96%, SD = 0.04, Mdn = 98%) indicated high engagement. Ratings at follow-up indicated high acceptability (item rating M = 1.77, SD = 0.73, Mdn = 1.45; scores range from 1-5, lower ratings indicate higher acceptability) and high satisfaction (CSQ M = 26.7, SD = 4.08, Mdn = 27.5; scores range from 8-32, higher scores indicate higher satisfaction). Descriptive statistics were used to characterize post-intervention outcomes. HDEs decreased by 45% from baseline while PrEP use intentions remained largely unchanged (decreased by 5%). Only three of twelve participants reported CAI at post-intervention. DISCUSSION: Results show high engagement, acceptability, and satisfaction with the mhealth modality and support the feasibility of this approach to address HDE among BLMSM. Future efficacy testing of this novel mhealth intervention via randomized controlled trial is warranted.

Sexual and gender politics inform relational expectations surrounding sexual experiences of Peruvian transgender women (TW) and men who have sex with men (MSM). We used the framework of sexual role strain, or incongruence between preferred sexual role and actual sexual practices, to explore potential conflicts between personally articulated identities and externally defined norms of gender and sexuality and its potential to increase HIV/STI risk. Cross-sectional individual- and dyad-level data from 766 TW and MSM in Lima, Peru were used to assess the partnership contexts within which insertive anal intercourse was practiced despite receptive role preference (receptive role strain), and receptive anal intercourse practiced despite insertive role preference (insertive role strain). Sexual role strain for TW was more common with non-primary partners, while for MSM it occurred more frequently in the context of a primary partnership. Receptive role strain was more prevalent for TW with unknown HIV status (reference: without HIV) or pre-sex drug use (reference: no pre-sex drug use). For homosexual MSM, receptive role strain was more prevalent during condomless anal intercourse (reference: condom-protected) and with receptive or versatile partners (reference: insertive). Among heterosexual or bisexual MSM, insertive role strain was more prevalent with insertive or versatile partners (reference: receptive), and less prevalent with casual partners (reference: primary). Our findings suggest TW and MSM experience different vulnerabilities during sexual role negotiation with different partner-types. Future studies should explore the impact of sexual role strain on condom use agency, HIV/STI risk, and discordances between public and private presentations of gender and sexual orientation. / National Institutes of Health / Revisión por pares

No description available.

Syphilis prevention in the United States continues to be an enduring public health challenge. Although syphilis is a curable infection, if left untreated it can result in severe, debilitating and potentially life-threatening complications. Routine screening for syphilis in high-risk populations remains an important prevention and control measure. Research consistently demonstrates the relative advantage of greater testing frequency in at-risk populations such as men who have sex with men (MSM) using both cost-effectiveness analyses and mathematical modeling. Despite this, frequency of screening for syphilis among MSM remains sub-optimal, and failure to screen MSM at recommended intervals may be attributable to clinicians’ perceptions related to syphilis screening in this population. The Theory of Planned Behavior (TPB) may help to elucidate the attitudes, social and professional norms, and perceived behavioral control that providers experience towards syphilis screening. The extent to which these cognitive-behavioral factors facilitate clinicians’ intentions to screening MSM for syphilis has not been previously evaluated. Using the constructs of the TPB, this study developed and validated a new survey tool with a national sample of physicians (n=123) who treat MSM and recruited through a proprietary email list and through passive recruitment on social media and provider Listservs. Results of the survey revealed variability in providers’ attitudes, social norms and perceived behavioral control, and these differed in association with self-reported syphilis screening intention and behavior. The survey was also used to validate a measurement model based on the TPB. This measurement model consisted of four factors: attitudes, social norms, perceived behavioral control and intention. This model was then used in structural equation modeling analysis to simultaneously test the strength of associations between these factors and a self-reported behavioral outcome. Results indicate that attitudes have a significant indirect effect on self-reported screening behavior mediated though intention. Perceived behavioral control was also strongly associated with self-reported behavior, as was intention to screen. By incorporating the TPB into a model of physician behavior, this study provides a framework for interventions targeted at increasing syphilis testing frequency in clinical practice. / Public Health

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Pre-exposure prophylaxis (PrEP) access is increasing in Latin America. We explored PrEP use among Spanish-speaking, Hornet geosocial networking application users from Latin American countries with limited PrEP data via an online survey completed between December 2018 and February 2019. A total of 718 Hornet users from 10 countries were included, of whom 72.1% reported PrEP awareness. Few (5.6%) were currently taking PrEP, though 32.1% intended to take PrEP in the subsequent 6 months. PrEP awareness was lower in 18–25 year olds compared to 26+ (62.4% vs. 75.6%, aOR 0.67, [95% CI 0.46–0.97]), and higher among those living in larger versus smaller cities (74.4% vs. 58.8%, aOR 1.96, [95% CI 1.25–3.07]) or countries with at least partial versus no PrEP policy adoption (79.1% vs. 60.8%, aOR 2.20, [95% CI 1.56–3.12]). Intention to use PrEP was higher among PrEP-eligible respondents (51.8% vs. 29.6%, aOR 2.26, [95% CI 1.26–4.07]) and those recently tested for a sexually transmitted infection (35.4% vs. 25.5%, aOR 1.58, [95% CI 1.01–2.48]). Efforts to expand PrEP use in Latin America should focus on national PrEP policy adoption, and research should explore barriers to awareness and use among young men who have sex with men. / National Institute of Mental Health / Revisión por pares

No / In this study, we assessed if the superimposition of incident sexually transmitted infections (STIs) on HIV phylogenetic analyses could reveal possible sexual behaviour misclassifications in our HIV-infected population. HIV-1 sequences collected between 1997 and 2014 from 1169 individuals attending a HIV clinic in Antwerp, Belgium were analysed to infer a partial HIV transmission network. Individual demographic, clinical and laboratory data collected during routine HIV follow-up were used to compare clustered and non-clustered individuals using logistic regression analyses. In total, 438 (37.5%) individuals were identified in 136 clusters, including 76 transmission pairs and 60 clusters consisting of three or more individuals. Individuals in a cluster were more likely to have a history of syphilis, Chlamydia and/or gonorrhoea (P < 0.05); however, when analyses were stratified by HIV transmission risk groups (heterosexual and men who have sex with men [MSM]), this association only remained significant for heterosexuals with syphilis (P = 0.001). Under closer scrutiny, this association was driven by six heterosexual men who were located in six almost exclusively MSM clusters. A parsimonious conclusion is that these six individuals were potentially misclassified as heterosexual. Improving the accuracy of sexual behaviour reporting could improve care.

Our understanding of humoral immune response to human papillomavirus (HPV) infection has been mainly derived from studies in women. Very little is known about humoral immune response to HPV in men. There is also a growing interest in understanding the burden of HPV exposure in the subgroups of the male population, including men who have sex with women (MSW), men who have sex with men (MSM) and men who have sex with both men and women (MSMW). This dissertation was undertaken to understand and characterize humoral immune response, measured by detectable serum antibody IgG, to HPV 6, 11, 16 and 18 infection, to estimates seroprevalence of HPV 6, 11, 16 and 18, to determine the associations of sociodemographic and sexual behavioral factors with seroprevalence of individual HPV types, and to evaluate the role of serum antibodies in the subsequent acquisition of infection with the same HPV type, genetically related and un-related HPV types. Three studies that compose of this dissertation were conducted within the framework of two longitudinal studies of HPV infection in men: a single-site natural history study of male residents of Tucson, Arizona (the 1st study: N=285); and a multinational natural history study of healthy men residing in São Paulo, Brazil, Cuernavaca, Mexico, and Tampa, Florida (the 2nd study: N=1477; the 3rd study: N=2187). Men were recruited using similar eligibility criteria in both natural history studies and followed every 6 months for a maximum of 18 months in the single-site study and 48 months in the multi-national study. HPV DNA status was assessed using the PGMY09/11 L1 consensus primer system and the Linear Array HPV Genotyping Protocol. Testing of serum antibodies to HPV 6, 11, 16 and 18 was performed with virus-like particle-based ELISA assays. Data from our studies indicate that exposure to HPV 6, 11, 16 and 18, the four HPV types targeted in the currently license HPV vaccines, is common. Of 285 male residents of Tucson, Arizona, 28.8% of them were seropositive to HPV 16 and/or 18 at study entry. Similarly, approximately one third of 1477 participants of the multi-national male HPV natural history study were seropositive to at least one vaccine HPV type, with the percentage of 21.8% in U.S. site, 33.4% in Mexico site, and 49.1% in Brazil site. It is also noted that seroprevalence of individual vaccine HPV types is greatly elevated among men of different sexual practices. Seroprevalence of HPV 6, 11, 16 and/or 18 was twice as high among MSM and MSMW compared to MSW. Likewise, seroprevalence of individual HPV types was two fold or higher among MSW and MSMW. Our findings suggest that the predominant predictors of seropositivity to HPV 6, 11, 16 and 18 are age and same-sex sexual behaviors. Seroprevalence increased with age among young-to-middle-aged men with significant upward age trends observed for HPV 11, 16 and 18. MSM, compared to MSW, more likely to be seropositive to HPV 16 or 18. Similarly, men who practiced same-sex anal sex, compared to those who did not, were significantly more likely to be seropositive to HPV 6, 11, 16 and 18, respectively. Among 276 men free of HPV 16 at enrollment in Tucson, We did not detect statistically significant associations between the baseline serum antibodies to HPV 16 and/or 18 and subsequent risk of infection with homogeneous HPV types or related-HPV types. Of 2187 men residing in three countries who tested HPV 16 negative at enrollment, the risk of subsequent HPV 16 infection was not associated with enrollment HPV 16 serum antibodies status. Our data provide important estimates of population exposure to vaccine HPV types for future studies modeling potential vaccine impact and vaccine cost effectiveness in men. Our findings also support strategic vaccination of males as an effective preventive measure for HPV-related diseases and cancers in men and their sex partners, men and women alike.

Prevention is key to keeping men who have sex with men (MSM) protected from Human Immunodeficiency Virus (HIV). Despite new and innovative HIV prevention resources such as pre-exposure prophylaxis (PrEP), factors such as education level, employment status, number of sexual partners, and access to health resources may inhibit certain populations from using PrEP. The purpose of this cross-sectional study was to examine the association between education level, employment status, number of sexual partners, and access to health resources and the use of PrEP among MSM. The fundamental cause theory was used to examine how socioeconomic barriers are associated with the use of PrEP among MSM in the United States. Secondary data from 217 surveys were collected from the Public Library of Science. Findings from multiple regression analyses indicated that employment status, access to health resources, and number of sexual partners were not associated with use of PrEP among MSM. Those who had at least some high school or a high school diploma were 3.98 times more likely to be likely to extremely likely to use PrEP, compared to those who had less than a high school education (OR = 3.98, p = .048). Those who had some college were 6.91 more likely to be likely to extremely likely to use PrEP, compared to those who had less than a high school education (OR = 6.91, p = .028). Findings may be used to assist public health professionals in identifying factors that prevent the use of PrEP. By addressing these health threats, and social barriers, specialists could have the ability to increase HIV prevention activity in populations that are more susceptible to being infected with HIV and may decrease HIV infections not only within the MSM population but also in other populations.

The overall aim of this thesis was to obtain an understanding of the dynamics of the HIV epidemic by estimating prevalence and exploring the relationship between HIV-related knowledge, attitudes, behavior, and HIV status in Nicaragua. Structured questionnaires were administered to adults from a health and demographic surveillance system in León, Nicaragua (Papers I–III). In-depth interviews and a survey were conducted among men who have sex with men (MSM, Paper IV). Blood sampling for HIV was carried out among 2,204 men and women (Paper I). Bivariate and multivariate analyses, including adjusted prevalence ratio (Papers I, II, IV), factor analysis, Cronbach’s alpha, and hierarchical regression analysis (Paper III) were performed. Thematic analysis was used with qualitative data (Paper IV). The prevalence of HIV in the general population was 0.35% (95% CI, 0.17–0.73). Those who have taken a HIV test were more likely to be females, younger, living in an urban setting, have a higher level of education, be married or cohabiting, and have no religious affiliation. HIV-related knowledge was lower among members of the general population than among MSM. Unprotected sex was reported more times with regular partners than with casual partners. Findings suggested that consistency of condom use and emotional attachment (steady relations) were inversely related. Stigma and discrimination were reported high in the general population; they appeared to be negatively associated with HIV-related knowledge, self-perception of HIV risk, HIV testing, and willingness to disclose HIV status in the event of being HIV-positive. Findings demonstrated an increasing tolerance towards same-sex attractions. MSM have a better understanding of HIV transmission than men and women of the general population. Although seven out of ten MSM and six out of ten women were concerned about becoming infected with HIV, inconsistent condom use was common. This study confirmed that Nicaragua has a low prevalence but high risk for HIV infection and transmission. Results underscore that social, behavioral, and cultural factors contribute to retard progress in achieving the Millennium Development Goals on reducing gender inequality and combating HIV/AIDS. Addressing these challenges depends not only on successful behavior change interventions, but requires a culturally gender-appropriate strategy.