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Our objective was to compare HIV prevalence between two national surveys among men who have sex with men in Brazil in 2009 and 2016. HIV prevalence was estimated stratifying by age and socioeconomic status. HIV prevalence increased from 11.9% [95% confidence interval (CI): 9.9-14.3], in 2009, to 19.1% (95% CI: 16.5 - 22.0), in 2016 [odds ratio (OR) = 1.8; 95% CI: 1.3-2.3] increasing 320% among Young MSM of low SES. Political leadership is needed to develop a scientifically sound and inclusive solution., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Brazil has many people living with HIV (PLWH) who are unaware of their serostatus. The public health system has recently added HIV self-testing (HIVST) for key populations such as men who have sex with men (MSM). This study estimates HIVST acceptability among Brazilian MSM and explores factors associated with acceptability among MSM who have never tested for HIV or who had a previous negative result., Methods: Respondent-driven sampling (RDS) was used to recruit 4176 MSM in 12 Brazilian cities in 2016 to this biological and behavioral surveillance study. We excluded from this analysis all MSM who were aware of their positive HIV serostatus. Descriptive, bivariate and multivariate analyses were conducted. Overall proportions were weighted with Gile's estimator in RDS Analyst software and 95% confidence intervals were calculated. The analyses of HIVST acceptability were stratified by prior HIV testing (never or one or more times)., Results: For this analysis, 3605 MSM were included. The acceptability of HIVST was 49.1%, lower among those who had never tested for HIV (42.7%) compared to those who had a previous HIV negative test (50.1%). In the subgroup of MSM who had never tested for HIV, those who reported discrimination or who had a medical appointment in the last 12 months reported higher HIVST acceptability. Among MSM who had a previous negative HIV test, only those reporting condomless receptive anal sex reported higher HIVST acceptability. In addition, we observed that high levels of knowledge of HIV/AIDS, taking part in lesbian, gay, bisexual, and transgender nongovernmental organizations (LGBT-NGO), or complete secondary or incomplete higher undergraduate education reported higher acceptability., Conclusions: The acceptability of HIVST was low among MSM, especially among those who never tested for HIV. Given access to HIVST in Brazil, we point to the need for programs that enhance promotion of testing addressed to MSM.

This study aimed to analyze the association between sociodemographic, programmatic and contextual factors and the receipt of money in exchange for sex among men who have sex with men (MSM). This is a multicenter, cross-sectional study conducted in ten Brazilian cities between 2008 and 2009. Adult MSM recruited through the Respondent Driven Sampling (RDS) were interviewed. Weighted Odds Ratio (ORw) was obtained through logistic regression, retaining the variables associated with the event (p < 0.05) in the final model. Of the total sample, 33.3% reported receiving money in exchange for sex in the last 12 months before the interview. The variables that were independently associated with the event were age less than or equal to 25 years, lower education, lower social classes, previous history of syphilis, using sites or services to find sexual partners in the previous month, very high risk behavior, using illicit drugs in the previous six months, self-identifying as heterosexual or bisexual, having suffered physical violence due to sexual orientation and having suicidal thoughts always or most of the time. It was observed that MSM who received money in exchange for sex had greater socioeconomic, programmatic and contextual vulnerability, potentially increasing the risk of HIV infection than the other MSM in the sample.

Respondent Driven Sampling study (RDS) is a population sampling method developed to study hard-to-reach populations. A sample is obtained by chain-referral recruitment in a network of contacts within the population of interest. Such self-selected samples are not representative of the target population and require weighing observations to reduce estimation bias. Recently, the Network Model-Assisted (NMA) method was described to compute the required weights. The NMA method relies on modeling the underlying contact network in the population where the RDS was conducted, in agreement with directly observable characteristics of the sample such as the number of contacts, but also with more difficult-to-measure characteristics such as homophily or differential characteristics according to the response variable. Here we investigated the use of the NMA method to estimate HIV prevalence from RDS data when information on homophily is limited. We show that an iterative procedure based on the NMA approach allows unbiased estimations even in the case of strong population homophily and differential activity and limits bias in case of preferential recruitment. We applied the methods to determine HIV prevalence in men having sex with men in Brazilian cities and confirmed a high prevalence of HIV in these populations from 3.8% to 22.1%.

Introduction: Discrimination based on sexual orientation can influence vulnerability to HIV, increasing exposure to risky sexual behavior among men who have sex with men (MSM)., Objectives: To analyze data using latent class analysis (LCA) to identify groups of individuals with specific patterns of discrimination based on sexual orientation (DSO)., Methods: Cross-sectional study using respondent-driven sampling in 12 Brazilian cities in 2016. LCA was used to characterize discrimination among MSM based on 13 variables in the survey questionnaire. The proportions of men reporting DSO and other variables of interest were estimated using Gile's Successive Sampling estimator., Results: Most MSM were young, single, had a religion, had a high school or college degree, black or brown skin color, and socioeconomic status classified as average. More than half of the participants reported that they had been discriminated against during the last 12 months due to their sexual orientation (65%), more than a third said they had felt afraid of walking in public places during the past 12 months, and about one-fifth of participants reported having been victims of physical or sexual assault due to DSO. DSO was classified into four latent classes: "very high", "high", "moderate" and "low", with estimates of 2.2%, 16.4%, 35.1%, and 46.19%, respectively., Conclusion: We observed a high proportion of discrimination against MSM in this study. The use of LCA differentiated parsimoniously classes of discrimination.

Introduction: High level of HIV/AIDS knowledge is required for an effective adoption of preventive strategies., Objective: To assess HIV/AIDS knowledge among men who have sex with men (MSM) in 12 Brazilian cities., Methods: Respondent-Driven Sampling method was used for recruitment. HIV/AIDS knowledge was assessed by Item Response Theory. Difficulty and discrimination parameters were estimated, and the knowledge score was categorized in three levels: high, medium, and low. Logistic regression was used for analysis., Results: Among 4,176 MSM, the proportion of high level of knowledge was 23.7%. The following variables were positively associated with high knowledge (p < 0.05): age 25+ years old, 12+ years of schooling, white skin color, having health insurance, having suffered discrimination due to sexual orientation, having had a syphilis test, and having received educational material in the previous 12 months. Exchanging sex for money was negatively associated., Conclusions: The proportion of only 23.7% of high HIV/AIDS knowledge was low. We should note that the only potential source of knowledge acquisition associated with high level of knowledge was receiving educational materials. Our study indicates the need for expansion of public prevention policies focused on MSM and with more effective communication strategies, including the development of knowledge that involves motivation and abilities for a safer behavior.

Introduction: This paper details the methods used in the second national Biological and Behavioral Surveillance Survey (BBSS) of HIV, syphilis, and hepatitis B and C among men who have sex with men in Brazil., Methods: Respondent-driven sampling (RDS) was used in 12 cities in 2016. The targeted sample size was initiated with five to six seeds in each city. HIV, syphilis, and Hepatitis B and C rapid tests were offered to participants. RDS Analyst with Gile's successive sampling (SS) estimator was used to adjust results as recommended and a weight for each individual was generated for further analysis. Data for the 12 cities were merged and analyzed using Stata 14.0 complex survey data tools with each city treated as its own stratum., Results: Duration of data collection varied from 5.9 to 17.6 weeks. 4,176 men were recruited in the 12 cities. Two sites failed to achieve targeted sample size due to a six-month delay in local IRB approval. No city failed to reach convergence in our major outcome variable (HIV)., Conclusion: The comprehensive BBSS was completed as planned and on budget. The description of methods here is more detailed than usual, due to new diagnostic tools and requirements of the new STROBE-RDS guidelines.

This paper reports human immuno-deficiency virus (HIV) prevalence in the 2nd National Biological and Behavioral Surveillance Survey (BBSS) among men who have sex with men (MSM) in 12 cities in Brazil using respondent-driven sampling (RDS).Following formative research, RDS was applied in 12 cities in the 5 macroregions of Brazil between June and December 2016 to recruit MSM for BBSS. The target sample size was 350 per city. Five to 6 seeds were initially selected to initiate recruitment and coupons and interviews were managed online. On-site rapid testing was used for HIV screening, and confirmed by a 2nd test. Participants were weighted using Gile estimator. Data from all 12 cities were merged and analyzed with Stata 14.0 complex survey data analysis tools in which each city was treated as its own strata. Missing data for those who did not test were imputed HIV+ if they reported testing positive before and were taking antiretroviral therapy.A total of 4176 men were recruited in the 12 cities. The average time to completion was 10.2 weeks. The longest chain length varied from 8 to 21 waves. The sample size was achieved in all but 2 cities.A total of 3958 of the 4176 respondents agreed to test for HIV (90.2%). For results without imputation, 17.5% (95%CI: 14.7-20.7) of our sample was HIV positive. With imputation, 18.4% (95%CI: 15.4-21.7) were seropositive.HIV prevalence increased beyond expectations from the results of the 2009 survey (12.1%; 95%CI: 10.0-14.5) to 18.4%; CI95%: 15.4 to 21.7 in 2016. This increase accompanies Brazil's focus on the treatment to prevention strategy, and a decrease in support for community-based organizations and community prevention programs.

Introduction: Periodic monitoring of sociobehavior characteristics at a national level is an essential component of understanding the dynamics the human immunodeficiency virus (HIV) epidemic worldwide, including Brazil., Methods: This paper compares descriptive sociobehavior characteristics in 2 national cross-sectional HIV biological behavioral surveillance surveys (BBSS) conducted in 2009 and 2016 among men who have sex with men (MSM) in Brazil. Respondent driven sampling (RDS) was used for recruitment in both years. Overall proportions were weighted according to Gile's estimator using RDS Analyst Software and 95% confidence intervals were calculated for comparisons between the 2 periods. Further comparisons were stratified by age groups (<25 and 25+ years old)., Results: Overall, 3749 and 4176 MSM were recruited in 2009 and 2016, respectively. In 2016, participants were younger than 25 years old (58.3%), with 12 or more years of education (70.4%), with higher socioeconomic status (40.7%), and had a higher proportion of whites (31.8%), as compared to 2009. Also, participants in 2016 reported less alcohol use and binge drinking, but used illicit drugs more frequently. There was an increase among MSM who self-reported their HIV risk as low and had low HIV knowledge while the proportion of those who were never tested for HIV dropped from 49.8% in 2009 to 33.8% in 2016. Although more than three-quarters received free condoms in both years, STD counseling remained low (32% and 38% for 2009 and 2016, respectively). Sexual risk behavior remained at high levels, especially unprotected anal receptive sex and sex with multiple partners. Younger MSM (<25 years old) showed riskier sexual practices than those 25+ years old, when comparing 2016 to 2009., Conclusions: Our results indicate a worrisome risk behavior trend among Brazilian MSM, especially among younger ones. These results can contribute for a better understanding of the HIV epidemics in Brazil, with timely shift in strategies so improved effectiveness in public health prevention efforts can be achieved.

Objective: To estimate self-reported discrimination due to sexual orientation among men who have sex with men (MSM) in Brazil and to analyze associated factors., Methods: A cross-sectional study of 3,859 MSM recruited in 2008-2009 with respondent driven sampling. Data collection conducted in health centers in 10 Brazilian cities. A face-to-face questionnaire was used and rapid HIV and syphilis tests conducted. Aggregated data were weighted and adjusted odds ratio estimated to measure the association between selected factors and self-reported discrimination due to sexual orientation., Results: The sample was predominantly young, eight plus years of schooling, pardo (brown), single, low-income, and identified themselves as gay or homosexual. The prevalence of self-reported discrimination due to sexual orientation was 27.7% (95%CI 26.2-29.1). Discrimination was independently associated with: age < 30 years, more years of schooling, community involvement and support, history of sexual and physical violence, suicidal thoughts, and unprotected receptive anal intercourse., Conclusions: The prevalence of self-reported discrimination among MSM in Brazil is high. These results challenge the assumptions that MSM-specific prevention and support programs are not required or that health professionals do not need special training to address MSM needs.

Sampling strategies such as respondent-driven sampling (RDS) and time-location sampling (TLS) offer unique opportunities to access key populations such as men who have sex with men (MSM) and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic.

Background: Men who have sex with men (MSM) are at increased risk of exposure to hepatitis B virus (HBV) compared with the general population. This study aims to assess the epidemiological and virological characteristics of HBV infection in a sample of MSM in Brazil, where data are scarce., Methods: A cross-sectional study was conducted among MSM in the City of Goiânia, Central Brazil, from March to November 2014, using Respondent-Driven Sampling (RDS). After signing the consent form, participants were interviewed and a blood sample collected. All samples were tested for HBV serological markers and HBV DNA. HBV nucleotide sequence analysis was also performed., Results: A total of 522 MSM were recruited in the study. The prevalence of HBV infection (current or past [presence of anti-HBc marker]) was 15.4% (95% CI: 8.7-25.8) and the rate of HBsAg carriers was 0.6% (95% CI: 0.2-1.6). About 40% (95% CI: 32.3-48.8) of the participants had serological evidence of previous HBV vaccination (reactive for isolated anti-HBs). In addition, 44.3% (95% CI: 36.1-52.9) were seronegative for all HBV markers. Age over 25 years old, receptive anal intercourse, previous sex with women, and history of sexually transmitted infections (STIs) were factors associated with HBV infection. HBV DNA was detected only in HBsAg-positive individuals. HBV isolates were classified into genotype A (subgenotypes A1 and A2), and some mutations were identified throughout the genome. Therefore, occult HBV infection was not observed in the study population., Conclusions: Public health strategies should be improved for the MSM population in order to prevent HBV and other STIs, as well as to provide appropriate management of patients with active infections.

This study aimed to identify incentives and barriers to HIV testing in men who have sex with men (MSM). This was a cross-sectional study of MSM who had lived at least three months in greater metropolitan Fortaleza, Ceará State, Brazil, 2010. The study recruited 391 men ≥ 18 years of age who reported sexual relations with men in the previous six months, using Respondent Driven Sampling. Personal network and socio-demographic data were collected and HIV testing was offered, analyzed with RDSAT 6.0 and Stata 11.0. The majority were young (40.3%), had 5 to 11 years of schooling (57.3%), were single (85.1%), had low income (37.6%), and 58.1% had tested for HIV some time in life. Incentive to test: certainty of not being infected (34.1%) and the exposure to national campaign Fique Sabendo [Know your Status] (34%). Barriers: trust in partner(s) (21%) and fear of discrimination if tested positive (20.3%). Policies should be developed to ensure test confidentiality and communication campaigns focusing on information gaps and encouragement for testing.

Human immunodeficiency virus (HIV) continues to disproportionately affect men who have sex with men (MSM); therefore, we investigated the sociodemographic, biological, and sexual behavioral risk factors associated with HIV infection in the city of Salvador, Bahia. This study is part of the national survey Behavior, Attitudes, Practices and Prevalence of HIV and Syphilis among men who have sex with men in 10 Brazilian Cities, which is a cross-sectional survey whose participants were selected by means of the respondent-driven sampling. Exact logistic regression analysis was used to measure the association of potential risk factors with HIV infection due to an HIV prevalence lower than 10% and a small sample size (383). The prevalence of HIV was 6.3% (95%CI 3.9-8.8) and the risk factors associated with HIV infection in our adjusted final model included having never been tested for syphilis (OR = 3.1; 95%CI 1.3 - 7.3) and having more than eight sexual partners (OR = 3.3; 95%CI 1.4 - 8.1). This study highlights the high prevalence of HIV among MSM in the sample compared with the general population and confirms the importance of testing for syphilis in the context of the HIV epidemic as early detection may provide opportunities to prevent sexually transmitted diseases.

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

The aim of this study was to assess risk factors associated with low levels of HIV testing among MSM recruited through respondent driven sampling (RDS) in Brazil. Of 3,617 participants, 48.4% had never tested previously for HIV. A logistic model indicated that younger age, lower socioeconomic class, education, poor HIV/AIDS knowledge, no history of cruising, and having been tested during the study were characteristics independently associated with low levels of previous HIV testing. The HIV testing rate among MSM in Brazil is still low in spite of the availability of a large number services providing universal and free access to HIV/AIDS diagnosis and treatment. To respond to low utilization, the authors propose a higher priority for testing for key populations such as MSM, expanded education, expanding testing sites and a welcoming and nonjudgmental environment in health services.

Objectives: To conduct the first population size estimation and biological and behavioral surveillance survey among men who have sex with men (MSM) in Angola., Design: Population size estimation with multiplier method and a cross-sectional study using respondent-driven sampling., Setting: Luanda Province, Angola. Study was conducted in a large hospital., Participants: Seven hundred ninety-two self-identified MSM accepted a unique object for population size estimation. Three hundred fifty-one MSM were recruited with respondent-driven sampling for biological and behavioral surveillance survey., Methods: Interviews and testing for HIV and syphilis were conducted on-site. Analysis used Respondent-Driven Sampling Analysis Tool and STATA 11.0. Univariate, bivariate, and multivariate analyses examined factors associated with HIV and unprotected sex. Six imputation strategies were used for missing data for those refusing to test for HIV., Main Outcome: A population size of 6236 MSM was estimated. Twenty-seven of 351 individuals were tested positive. Adjusted HIV prevalence was 3.7% (8.7% crude). With imputation, HIV seroprevalence was estimated between 3.8% [95% confidence interval (CI): 1.6 to 6.5] and 10.5% (95% CI: 5.6 to 15.3). Being older than 25 (odds ratio = 10.8, 95% CI: 3.5 to 32.8) and having suffered episodes of homophobia (odds ratio = 12.7, 95% CI: 3.2 to 49.6) significantly increased the chance of HIV seropositivity., Conclusions: Risk behaviors are widely reported, but HIV seroprevalence is lower than expected. The difference between crude and adjusted values was mostly due to treatment of missing values in Respondent-Driven Sampling Analysis Tool. Solutions are proposed in this article. Although concerns were raised about feasibility and adverse outcomes for MSM, the study was successfully and rapidly completed with no adverse effects.

Objective: To conduct the first national biological and behavioral surveillance survey for HIV among MSM in Brazil., Design: A cross-sectional surveillance study utilizing Respondent Driven Sampling (RDS) in 10 cities, following formative research. Planned sample: 350 MSM reporting sex with another man in the last 12 months, at least 18 years of age, and residing in the city of the study., Methods: Conventional RDS recruitment. Results were calculated for each city using RDSAT 5.6. For the national estimate, a new individual weight using a novel method was calculated. The 10 cities were aggregated, treated as strata and analyzed using STATA11.0. Self-reported HIV status and logistic regression was used to impute missing values for serostatus, an important issue for RDSAT., Results: A total of 3859 MSM were interviewed. Sample was diverse, most self-identified as mulatto or black, were social class C or below, and had relatively low levels of education. More than 80% reported more than one partner in the last 6 months. Only 49% had ever tested for HIV. HIV prevalence among MSM ranged from 5.2 to 23.7% in the 10 cities (3.7-16.5% without imputation) and was 14.2% for all cities combined with imputation. The overall prevalence was two and three times higher than that estimated for female sex workers and drug users, respectively, in Brazil. Half of those who tested HIV positive were not aware of their infection., Conclusion: The AIDS epidemic in Brazil is disproportionately concentrated among MSM, as has been found in other countries. Renewed efforts to encourage testing, prevention and treatment are required.

Introduction: The aim of this study was to evaluate the reliability of self-reported HIV among men who have sex with men (MSM) in Brazil., Methods: MSM 18 years of age or older were recruited to a multicenter study using respondent-driven sampling. We compared self-report of the HIV test with a rapid HIV test using the kappa coefficient., Results: A total of 3859 MSM were recruited, and 39% reported ever having an HIV test; their results were reported and they agreed to a new test. Agreement between self-report and the test was very good (kappa = 0.88)., Conclusion: Our results suggest that self-report of HIV infection is a reliable indicator among MSM.

Background: : There are few studies on HIV subtypes and primary and secondary antiretroviral drug resistance (ADR) in community-recruited samples in Brazil. We analyzed HIV clade diversity and prevalence of mutations associated with ADR in men who have sex with men in all five regions of Brazil., Methods: : Using respondent-driven sampling, we recruited 3515 men who have sex with men in nine cities: 299 (9.5%) were HIV-positive; 143 subjects had adequate genotyping and epidemiologic data. Forty-four (30.8%) subjects were antiretroviral therapy-experienced (AE) and 99 (69.2%) antiretroviral therapy-naïve (AN). We sequenced the reverse transcriptase and protease regions of the virus and analyzed them for drug resistant mutations using World Health Organization guidelines., Results: : The most common subtypes were B (81.8%), C (7.7%), and recombinant forms (6.9%). The overall prevalence of primary ADR resistance was 21.4% (i.e. among the AN) and secondary ADR was 35.8% (i.e. among the AE). The prevalence of resistance to protease inhibitors was 3.9% (AN) and 4.4% (AE); to nucleoside reverse transcriptase inhibitors 15.0% (AN) and 31.0% (AE) and to nonnucleoside reverse transcriptase inhibitors 5.5% (AN) and 13.2% (AE). The most common resistance mutation for nucleoside reverse transcriptase inhibitors was 184V (17 cases) and for nonnucleoside reverse transcriptase inhibitors 103N (16 cases)., Conclusions: : Our data suggest a high level of both primary and secondary ADR in men who have sex with men in Brazil. Additional studies are needed to identify the correlates and causes of antiretroviral therapy resistance to limit the development of resistance among those in care and the transmission of resistant strains in the wider epidemic.

This paper focuses on recent trends in risky sexual practices for HIV/AIDS among men who have sex with men (MSM) in Fortaleza, Ceará State, Brazil. Four cross-sectional surveys were conducted (1995, 1998, 2002, and 2005) among MSM 14 years or older who reported oral or anal sex in the previous 12 months. Sexual practices were considered risky whenever the respondent reported unprotected receptive or insertive anal intercourse in the six months preceding the interview. Different selection techniques were used to recruit the study population: snowball (1995, 1998, 2002 - 32%); time-space sampling (2002 - 68%); and respondent-driven sampling (2005). Analyses were based on the comparison between proportions. High rates of risky sexual practices were reported in 1995 (49.9%), decreasing in 1998 (32.6%), increasing again in 2002 (51.3%), and showing the lowest level in 2005 (31.4%). Participants with more schooling increased their risky practices from 1998 to 2002, decreasing in 2005. Among individuals with medium or low schooling, risky behavior declined from 2002 to 2005. The article highlights the need for behavioral surveillance to properly address STD/HIV prevention.

Obtaining samples of populations at risk for HIV challenges surveillance, prevention planning, and evaluation. Methods used include snowball sampling, time location sampling (TLS), and respondent-driven sampling (RDS). Few studies have made side-by-side comparisons to assess their relative advantages. We compared snowball, TLS, and RDS surveys of men who have sex with men (MSM) in Forteleza, Brazil, with a focus on the socio-economic status (SES) and risk behaviors of the samples to each other, to known AIDS cases and to the general population. RDS produced a sample with wider inclusion of lower SES than snowball sampling or TLS-a finding of health significance given the majority of AIDS cases reported among MSM in the state were low SES. RDS also achieved the sample size faster and at lower cost. For reasons of inclusion and cost-efficiency, RDS is the sampling methodology of choice for HIV surveillance of MSM in Fortaleza.