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HIV Pre-exposure prophylaxis (PrEP) is an effective prevention tool, but there are still few studies about PrEP uptake among adolescents. We aimed to analyze the PrEP uptake process and factors associated with daily oral PrEP initiation among adolescent men who have sex with men (aMSM) and transgender women (aTGW) in Brazil. Baseline data from the first demonstration PrEP cohort study among aMSM and aTGW 15–19 years old (yo) ongoing in three large Brazilian cities (PrEP1519). After completing informed consent procedures, participants were enrolled in the cohort from February/2019 to February/2021. A socio-behavioral questionnaire was applied. Factors associated with PrEP initiation were assessed using a logistic regression model with adjusted prevalence ratios (aPR) and 95% confidence intervals (95%CI). Among recruited participants, 174 (19,2%) were aged 15–17 yo and 734 (80,8%) 18–19 yo. The rate of PrEP initiation was 78.2% and 77.4% for 15–17 yo and 18–19 yo, respectively. Factors associated with PrEP initiation were: black or mixed race (aPR 2.31; 95%CI: 1.10–4.84) among the younger adolescents 15–17 yo; experienced violence and/or discrimination due to their sexual orientation or gender identity (aPR 1.21; 95%CI: 1.01–1.46); transactional sex (aPR 1.32; 95%CI: 1.04–1.68); and having had between 2 to 5 sexual partners in the previous three months (aPR 1.39; 95%CI: 1.15–1.68) among those 18–19 yo. Unprotected receptive anal intercourse in the previous six months was associated with PrEP initiation in both age groups (aPR 1.98; 95%CI: 1.02–3.85 and aPR 1.45; 95%CI: 1.19–1.76 among 15–17 yo and 18–19 yo, respectively). The biggest challenge to promoting PrEP use for aMSM and aTGW was in the first steps of the PrEP uptake process. Once they were linked to the PrEP clinic, initiation rates were high. [ABSTRACT FROM AUTHOR]

Using baseline data from the PrEP1519 cohort, in this article we aimed to analyze: (i) the effectiveness of demand creation strategies (DCS) to enroll adolescent men who have sex with men (AMSM) and adolescent transgender women (ATGW) into an HIV combination prevention study in Brazil; (ii) the predictors of DCS for adolescents' enrollment; and (iii) the factors associated with DCS by comparing online and face-to-face strategies for enrollment. The DCS included peer recruitment (i.e., online and face-to-face) and referrals from health services and non-governmental organizations (NGOs). AMSM and ATGW who agreed to participate in the study could opt to enroll in either PrEP (PrEP arm) or to use other prevention methods (non-PrEP arm). Bivariate and multivariate analyses were conducted and logistic regression odds ratios were estimated. The DCS reached 4529 AMSM and ATGW, the majority of which were derived online (73.8%). Of this total, 935 (20.6%) enrolled to participate (76.6% in PrEP arm and 23.4% in non-PrEP arm). The effectiveness of enrolling adolescents into both arms was greater via direct referrals (235/382 and 84/382, respectively) and face-to-face peer recruitment (139/670 and 35/670, respectively) than online (328/3342). We found that a combination under DCS was required for successful enrollment in PrEP, with online strategies majorly tending to enroll adolescents of a higher socioeconomic status. Our findings reinforce the need for DCS that actively reaches out to all adolescents at the greatest risk for HIV infection, irrespective of their socioeconomic status. [ABSTRACT FROM AUTHOR]

Standardized treatment regimens for chronic hepatitis B (CHB) are crucial in suppressing viral replication, disease progression and the development of complications. However, information on routine compliance with such therapeutic recommendations in medical practice is rare. Aim: To evaluate the application of Brazilian therapeutic guidelines for CHB within the scope of the Unified Health System in Minas Gerais state. Four key recommendations from the national guidelines were compared with data from treated patients: (i) eligibility to start treatment; (ii) type of treatment applied; (iii) rescue antiviral therapy; and (iv) monitoring of virological response. Most physicians (69.8%) declared to adopt these guidelines, while 10 of them were unaware. However, according to the criteria established by the guidelines, only 39.5% of treated patients should have been considered "truly" eligible to start treatment and only 67.6% of these underwent the recommended pharmacological treatment. The virological response was laboratory monitored in just over a third of patients. Rescue therapy was adequately supplanted in 41.2% of patients previously treated with lamivudine. There was low compliance with national guidelines by public service physicians in Brazil, highlighting the need to raise awareness of the importance of its adherence to expand the control of CHB. Thus, increasing the adherence of health professionals to this tool is a current challenge for health institutions and managers. [ABSTRACT FROM AUTHOR]

Frequent contact with hazardous materials makes waste collection a potentially unhealthy activity. This article assesses the perception of waste management workers regarding work-related accidents in domestic and health service contexts in Brazil. Six focus groups were performed between June 2014 and August 2015. The aims of this study were to apprehend different aspects of the participants' health, workers' experiences of work-related accidents and perception of risks. Cuts and puncture injuries were reported most frequently in the line of work and were often considered as irrelevant. Immunization against hepatitis B was not common among all workers, which increases the risk of infection for those individuals. Finally, it is considered urgent to consolidate an inclusive space in which workers can have discussions on their health. [ABSTRACT FROM AUTHOR]

Background: There has recently been an increase in HIV infection rates among men who have sex with men (MSM). This study aimed at investigating risk factors associated with incident HIV infection in a MSM cohort–Project Horizonte, Belo Horizonte, Minas Gerais, Brazil. Methodology: This is a nested case-control study in an ongoing open cohort of homosexual and bisexual men, carried out in 1994–2010, during which 1,085 volunteers were enrolled. Each HIV seroconverted volunteer (case) was compared with three randomly selected HIV negative controls, matched by admission date and age (±3 years). During follow-up, 93 volunteers seroconverted and were compared with 279 controls. Principal Findings: The risk factors associated with HIV seroconversion were: contact with partner’s blood during sexual relations (OR 3.7; 95% CI 1.2–11.6), attendance at gay saunas in search for sexual partners (OR 2.6; 95% CI 1.3–5.4), occasional intake of alcohol when flirting and engaging in sexual activity (OR 2.5; 95% CI 1.3–5.1), inconsistent use of condoms in receptive anal sex (OR 2.4; 95% CI 1.1–5.4), little interest to look up information about AIDS (OR 2.6; 95% CI 1.0–6.7) particularly in newspapers (OR 3.4; 95% CI 1.4–8.1). Conclusions: This study shows that MSM are still engaging in risk behavior, such as unprotected anal intercourse, despite taking part in a cohort study on various preventive measures. New preventive strategies in touch with the epidemic’s development and the specificities of this particular population are needed. [ABSTRACT FROM AUTHOR]

Abstract: This study aims at estimating the prevalence of Leishmania infection among HIV-infected patients through the use of non-invasive tests. The study was conducted in three Infectious Diseases Services in two large Brazilian cities, both endemic areas for visceral leishmaniasis. Three hundred and eighty-one asymptomatic patients were enrolled whose ages ranged from 19 to 58 years old; 63.5% were men; mean TCD4+ was 380 cells/μl; and mean viral load was 153800 copies/ml. All individuals were tested for Leishmania infection through: ELISA using crude Leishmania infantum (ELISA), ELISA using the recombinant K39 antigen (rK39), indirect fluorescent antibody test (IFAT) and PCR targeted to kDNA region. The tests’ positivity were: 10.8% (ELISA), 3.9% (IFAT), 0.8% (rK39), 6.3% PCR and 20.2% (overall, at least one positive test), with no statistical correlation between positivity and clinical and laboratorial variables. Concordance among tests was low (Kappa <0.20). Prevalence of Leishmania asymptomatic infection was high in this population, reinforcing the need for attention in the evaluation of HIV patients from endemic areas. New efforts are needed to develop more specific and sensitive tests to diagnose Leishmania asymptomatic infection. Highly active antiretroviral therapy (HAART) seems to have a protective role against disease progression in co-infected individuals. [Copyright &y& Elsevier]

The article discusses a study to assess HIV-related knowledge, sources of information, risk behaviors, and prevention beliefs and strategies among street youths in Belo Horizonte, Brazil. Individual interviews were conducted with 379 youth who work and live on the streets of Belo Horizonte. Respondents demonstrated high levels of factual knowledge about HIV transmission coupled with high levels of misconceptions about casual transmission and intermediate levels of knowledge about prevention. Only 54% of the respondents had heard about AIDS, and 37.5% said they talked to someone about AIDS. the proportion of youth taking effective precautions was low. Among the 247 youth who had initiated sexual activity, lifetime condom use was reported by 18%, and condom use at last intercourse by 10%. Youth with higher levels of knowledge were more likely to report behavior changes to avoid HIV infection. These findings underscore the urgent need for prevention programs tailored to street youth in developing countries. The findings reported in this paper demonstrate that Brazilian street youth are at risk of HIV infection. Prevention programs are needed to increase understanding of transmission mechanisms, decrease beliefs in casual contagion, and promote effective risk-reduction strategies.

The Sociedade Brasileira de Alergia e Immunopatologia (SBAI), or Brazilian Society for Allergy and Imnunopathology, was established in 1962 to improve the practice of and the research on allergology and clinical immunology in Brazil. The SBAI will hold its main regional scientific meeting in Salvador, Bahia, from November 6-9, 1997, and the Brazilian Congress of Allergy and Immunopathology will he held in Belo Horizonte, Minas Gerais, in November 1998.

Abstract: Background: Human immunodeficiency virus type 1 (HIV-1) subtype B predominates in Brazil, but in the southern region subtype C is the most frequent, followed by subtypes B, F1 and recombinant forms. In southern Brazil, these subtypes co-circulate in subjects with homogeneous demographic and clinical features, enabling a better understanding of the role of HIV-1 subtypes on the characteristics of infection. Objectives: To evaluate the prevalence of different HIV-1 subtypes in subjects with recent diagnosis for HIV infection in the extreme south of Brazil, and to study their association with demographic, behavioral, clinical and laboratorial characteristics. Study design: We have determined the genetic sequence of viral protease and reverse transcriptase (polymerase, connection and RNase H domains) isolated from studied subjects. Viral subtype was inferred by comparison with reference HIV sequences, and recombination was determined with Simplot analysis. The association of HIV-1 subtypes with studied characteristics was evaluated by chi-square, Fisher''s exact, Student''s t and Kruskal–Wallis tests. Results: Two hundred and forty-five HIV isolates were molecularly characterized, and the association with variables was studied for 233 (95.1%) patients. Of those, 46.8% followed AIDS defining criteria. HIV-1C was responsible for 56.3% of infections, and was associated with heterosexual transmission (p =0.001) and with higher CD4+ T-cell counts (p =0.02). Conclusions: The molecular epidemiology of HIV-1 in the southernmost Brazil is currently steady with predominance of HIV-1C. This is the first study showing a robust association of the infection by this subtype and heterosexual transmission in the state of Rio Grande do Sul, Brazil. [Copyright &y& Elsevier]

Abstract: Background: Major and accessory drug resistance mutations have been recently characterized in the C-terminal RT subdomains of HIV-1, connection and RNase H. However, their presence in treatment-naïve patients infected with HIV-1 non-B subtypes remains largely unknown. Objectives: To characterize the patterns of primary resistance at the C-terminal RT subdomains of HIV-1 infecting subjects in the southern region of Brazil, where HIV-1 subtypes B and C co-circulate. Study design: Plasma viral RNA was extracted from patients recently diagnosed for HIV infection (2005–2008). The protease and reverse transcriptase regions were PCR-amplified and sequenced. Infecting HIV subtypes were assigned by phylogenetic inference and drug resistance mutations were determined following the IAS consensus and recent reports on C-terminal RT mutations. Results: The major mutation to NNRTI T369I/V was found in 1.8% of patients, while A376S was present in another 8.3%. In the RNase H domain, the compensatory mutation D488E was more frequently observed in subtype C than in subtype B (p =0.038), while the inverse was observed for mutation Q547K (p <0.001). The calculated codon genetic barrier showed that 22% of subtype B isolates, but no subtype C, carried T360, requiring two transitions to change into the resistance mutation 360V. Conclusions: Major resistance-conferring mutations to NNRTI were detected in 10% of RT connection domain viral sequences from treatment-naïve subjects. We showed for the first time that the presence of specific polymorphisms can constrain the acquisition of definite resistance mutations in the connection and RNase H subdomains of HIV-1 RT. [Copyright &y& Elsevier]

Describes the design and data collection methods of the Project Horizonte, an open cohort of homosexual and bisexual HIV-1 negative men and a component of the Minas Gerais AIDS Vaccine Program of the Federal University of Minas Gerais in Brazil. Objectives of the project; Blood collection and laboratory tests; Project Horizonte HIV infection incidence rates; Characteristics of single-visit participants versus participants

Purpose: This study analyzed the sociodemographic and behavioral characteristics of adolescent men who have sex with men (aMSM) and transgender women (aTGW) initiating oral pre-exposure prophylaxis (PrEP) in human immunodeficiency virus (HIV) prevention clinics., Methods: PrEP1519 is a prospective, multicenter, open-label PrEP demonstration cohort study of aMSM and aTGW aged 15-19 years living in three large Brazilian capital cities. For this analysis, we included adolescents who enrolled in PrEP1519 from February 2019 to August 2021. Adolescents who visited PrEP clinics were classified into four groups based on PrEP eligibility and on their decision to use PrEP: (1) ineligible for same-day PrEP initiation; (2) eligible for same-day PrEP initiation, initiated PrEP at first visit; (3) eligible for PrEP initiation, initiated PrEP after the first visit; and (4) eligible for same-day PrEP initiation but declined. The groups that were eligible for same-day PrEP initiation were compared using the Chi-square and Fisher's exact tests., Results: Of the 1,254 adolescents enrolled in the PrEP1519 study, 61 (4.9%) were considered ineligible for same-day PrEP initiation. Of the 1,193 eligible for same-day PrEP initiation, 1,113 (93.3%) initiated PrEP [1,054 initiated PrEP in the first visit (88.3%) and 59 in subsequent visits (4.9%)] and 80 (6.7%) did not. Despite 90% of the PrEP decliners reporting a low risk of HIV infection, most reported condomless anal sex in the past six months (70%)., Discussion: Same-day PrEP initiation among aMSM and aTGW was high, highlighting that this strategy was important to promote PrEP initiation among adolescents with increased vulnerability to HIV in Brazil., (Copyright © 2023 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: This study aimed to describe pre-exposure prophylaxis (PrEP) for HIV discontinuation in adolescent men who have sex with men (aMSM) and adolescent transgender women (aTGW) and to identify factors associated with discontinuation., Methods: The PrEP1519 study included a cohort of aMSM and aTGW aged 15-19 years old, and it was conducted in three large Brazilian capital cities. For this analysis, we included adolescents who initiated PrEP. PrEP discontinuation was defined as no possession of PrEP pills for >90 days. Kaplan-Meier curves were used to analyze the probabilities of discontinuation, and survival distributions stratified by covariates were compared using log-rank or Wilcoxon tests. Cox regression models were used to estimate the adjusted hazard ratio (aHR) with a 95% confidence interval (95% CI)., Results: We included 908 adolescents, 829 (91.30%) aMSM and 79 (8.70%) aTGW, most of whom were 18-19 years (80.29%). The incidence rate of discontinuation was 75.6 per 100 person-years. The probability of discontinuation was 52.61% in the first year. The multivariate analysis demonstrated that the aTGW (aHR = 1.63; 95% CI: 1.02-1.64) and adolescents with a medium (aHR = 1.29; 95% CI: 1.02-1.64) or low (aHR = 1.65; 95% CI: 1.29-2.12) perceived risk of HIV infection had an increased risk of discontinuation, whereas the adolescents with a partner living with HIV had a lower risk of discontinuation (aHR = 0.57; 95% CI: 0.35-0.91)., Discussion: Adolescents with a high risk for discontinuation may need additional support that emphasizes the value of PrEP as a tool for HIV prevention because PrEP discontinuation was associated with a disconnect between HIV risk perception and HIV prevention., (Copyright © 2023 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: This study aimed at describing the prevalence of symptoms of depression among 15-19 year old adolescent men who have sex with men (aMSM) and transgender women (aTGW), who were recruited in an HIV pre-exposure prophylaxis cohort study in three Brazilian capital cities. The study also examined potential associations, including violence and discrimination, with severe symptoms of depression among aMSM., Methods: This is a cross-sectional study of baseline data among 730 aMSM and 56 aTGW recruited between February 2019 and February 2021. Sociodemographic and behavioral data were collected. The 20-item Center for Epidemiologic Studies Depression scale was used to screen for symptoms of depression. Scores of ≥22 points indicate the presence of severe symptoms associated with major depression. Logistic regression was used to assess independent associations among aMSM, adjusting for sociodemographic variables., Results: Our findings indicate a high prevalence of symptoms of depression (overall prevalence = 58.5% and 69.6%; 21.2% and 25.0% for mild/moderate, and 37.3% and 44.6% for severe) among these aMSM and aTGW, respectively. Psychological violence (aOR = 1.74; 95% CI = 1.12-2.70), sexual violence (aOR = 1.79; 95% CI = 1.07-2.98), and discrimination due to sexual orientation (aOR = 1.71; 95% CI = 1.23-2.38) were independently associated with severe symptoms of depression in aMSM., Discussion: The high prevalence of severe symptoms of depression and its association with psychological and sexual violence and discrimination creates cycles of vulnerability and carries important public health implications. Thus, our findings indicate public policies should consider assessing depression, psychological and sexual violence, as well as discrimination, especially in populations that will be targeted by interventions, such as the use of pre-exposure prophylaxis., (Copyright © 2023 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: To explore legal and ethical challenges related to adolescents' participation in human immunodeficiency virus (HIV) research that may affect their best interests., Methods: We analyzed the ethical principles and legal aspects of the participation of 15-17-year-old men who have sex with men and transgender women in the pre-exposure prophylaxis (PrEP) 1519 study, a PrEP demonstration cohort study in three Brazilian cities. The analyses of ethics review committees' (ERCs) evaluations and court decisions followed ethical and human rights principles. An HIV vulnerability score was created, and descriptive statistics and multivariate logistic regression were performed using data from 347 participants., Results: The ERCs evaluated the benefits and risks of research participation, all finding that the benefits outweighed the risks. ERCs deferred responsibility for decisions about waiving parental consent to the judiciary. State courts reached different decisions about waiving parental consent, reflecting variation in recognition of adolescents' evolving capacities and the adolescent as a subject of sexual rights and the primary agent capable of deciding on their health and best interests. The most vulnerable adolescent participants were found in sites where the blanket waiver was in place., Discussion: Judicializing the ethical review process is detrimental to fulfilling the ethical principle of justice and vulnerable adolescents' access to health research. ERCs must be sufficiently independent and autonomous and have the capacity to respect, protect, and help fulfill the rights of participants while ensuring the generation of adequate evidence to inform public health practice., (Copyright © 2023 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the adherence, safety, and feasibility of pre-exposure prophylaxis (PrEP) in real-world settings among adolescent men who have sex with men (AMSM) and transgender women (ATGW)., Methods: PrEP1519 is a single-arm, multicentric demonstration cohort study of daily oral PrEP among AMSM and ATGW aged 15 to 19 years in Brazil. Study visits occurred at baseline, weeks 4, 12, and then quarterly until 96 weeks. Descriptive statistics and a mixed logistic model for longitudinal data evaluated the factors associated with high adherence., Results: One thousand sixteen AMSM and ATGW accessed the PrEP1519 clinics. Of those, 998 (98.2%) underwent clinical triage. Forty one were diagnosed with human immunodeficiency viruses (HIV) at baseline (4.0%) and 79 (7.9%) were not eligible for PrEP. Of the 878, 795 (90.5%) enrolled in PrEP, 82 (10.3%) were lost to follow-up, and 713 were included. There was no significant decrease in creatinine clearance; only two participants had grade-III aspartate aminotransferase elevation. Incident HIV infection occurred in eight participants (incidence rate [IR] = 1.64 per 100 person-years [PY]): two in 15-17 years (IR = 2.24 per 100 PY) and six in 18-20 years (IR = 1.51 per 100 PY). PrEP adherence was higher among those with more years of schooling, those reporting no difficulties in PrEP use due to side effects, and who had low HIV risk perception in the past three months., Discussion: PrEP for AMSM and ATGW was safe and feasible in real-world settings. However, a higher IR among young adolescents and a higher adherence among less vulnerable people indicate the need for greater care, considering the specificities of this age group., (Copyright © 2023 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Syphilis has reemerged as a serious public health problem in Brazil and worldwide, disproportionately affecting men who have sex with men (MSM) and travestis and transgender women (TrTGW). Studies on sexually transmitted infections (STI) in adolescents from these key populations are relatively scarce. This is a Brazilian multi-center, cross study with prevalence analysis, using as baseline the PrEP1519 cohort of sexually active MSM and TrTGW adolescents, recruited from April 2019 to December 2020. Analyses were made using the dimensions of vulnerability to STI/HIV and logistic regression models were conducted to estimate the odds ratios of the association between the predictor variables and positive treponemal test for syphilis at the moment of entry in the study. In total, 677 participants were analyzed; participants' median age was 18.9 years (IQR: 18.1-19.5); 70.5% (477) self-declared as black; 70.5% (474), as homosexuals/gays; and 48 (7.1%), as trans women or travestis. The baseline prevalence of syphilis was 21.3%. In the final logistic regression model, higher chance of syphilis was associated with: self-reported episode of STI in the last 12 months (OR = 5.92; 95%CI: 3.74-9.37), sex worker (OR = 3.39; 95%CI: 1.32-8.78), and < 11 years of schooling (OR = 1.76; 95%CI: 1.13-2.74). The prevalence of syphilis among MSM/TrTGW adolescents aged from 15 to 19 years was alarming, much higher than the described for the general population within this age range and associated with vulnerability factors. This reinforces the urgent need to strengthen public health programs to debate about race, gender, sexuality, and prevention.

At the end of 2017, Brazil adopted HIV pre-exposure prophylaxis (PrEP) as part of a combination prevention strategy for the most at-risk populations. However, Brazil does not have specific guidelines for PrEP use among adolescents aged < 18 years. Therefore, researchers from different health disciplines conducted PrEP1519, the first PrEP demonstration cohort study, ongoing in three Brazilian cities - Salvador, Belo Horizonte, and São Paulo - among adolescent men who have sex with men and transgender women, aged 15-19 years. This study aims to evaluate the effectiveness of PrEP in real-world settings. Quantitative and qualitative methods were integrated to obtain data on PrEP acceptability, uptake, use, and adherence. Moreover, comprehensive services and friendly environments were implemented in the PrEP1519 clinics. This study aims to describe the collaborative efforts of interdisciplinary practices in the development of the PrEP1519 study. The articulation of researchers from different institutions and areas is challenging; but it also allows for a broader outlook on questions regarding the direction of the research, while enriching the decisions needed to be taken during the interactions and negotiations among the different individuals, including the youth team and participants. Furthermore, it reflects on the communication process between cultures and languages considering the trans-epistemic arena of knowledge production about HIV, sexually transmitted infections, PrEP, and other combination prevention strategies for adolescents.

Based on the incorporation of pre-exposure prophylaxis (PrEP) as an HIV prevention strategy and considering the need to comprehend the use of medication among young people, this article analyzes narratives of gay men and transgender women from Belo Horizonte, Minas Gerais State, Brazil, participating in the PrEP1519 study. This is a qualitative research, based on the interpretative anthropology, developed by 10 in-depth interviews with PrEP users followed-up for at least three months between October and November 2019. The results showed that the drug was seen as the main motivation for participating in the study and as a strategy combined with the use of condoms, whether as additional prevention, or assuming the leading role. The medication revealed signs built by the gender performances and their relation to other medications, especially the experience of trans girls in hormonal therapy. Regarding the socialization of the use of PrEP, the narratives showed that there was no secret between the couples, which did not meant that stigmas on the association with HIV did not exist, mainly in the virtual context. In the family environment, they reported questions about the preventive function of the medication and the voluntary nature of the participation in the study. The youth's narratives revealed plural meanings of the medication and its social use, composing both the boys' and girls' performances. The signs attributed to the medication indicated that in addition to maintenance of health, the medication improves life and sexual freedom.

Background: Chronic hepatitis B (CHB) affects 257 million people worldwide. However, the proportion of patients eligible for treatment in the public health system has not been established. This study describes the clinical and laboratory profiles of untreated CHB patients and estimates the eligibility rate for antiviral therapy in accordance with the Brazilian Clinical Protocol and Therapeutic Guidelines., Methods: Records of 670 CHB patients were collected from May 2012 to September 2013 in Minas Gerais. Data from each patient were analyzed by hepatitis B virus (HBV) management., Results: 461 CHB patients were treatment-naive. Of these, 23 were HBeAg-positive, 352 were HBeAg-negative, and 14 were clinically diagnosed with cirrhosis. Periodic monitoring was performed in only three patients. However, 9.3% of untreated patients met the eligibility criteria for HBV treatment., Conclusions: Few CHB patients were active carriers and eligible candidates for antiviral therapy. This study revealed inadequate pre-treatment conduct in the Brazilian public health system, emphasizing the need for regular laboratory follow-up for patients initially not eligible for treatment. Such information may indirectly subsidize the planning and improvement of actions and services related to optimal HBV management in the public sphere.

In the space of four decades, Brazil has faced two serious pandemics: human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and Coronavirus disease 2019 (COVID-19). The country's response to HIV/AIDS was coordinated by several stakeholders and recognised the importance of scientific evidence in guiding decision-making, and a network offering monitoring and antiretroviral treatment was provided through coordinated efforts by the country's universal health system. Conversely, the lack of a centrally coordinated strategy and misalignment between government ministries regarding the COVID-19 pandemic response, together with the denial of scientific evidence, promotion of ineffective treatments and insufficient vaccination efforts, have all led to the uncontrolled spread of infection, the near-total collapse of the health system and excess deaths.

Understanding the social conditions and immunological characteristics that allow some human immunodeficiency virus (HIV)-exposed patients to remain uninfected represents an on-going challenge. In this study, the socio-demographic and sexual behaviour characteristics and immune activation profiles of uninfected individuals exposed to HIV-infected partners were investigated. A confidential and detailed questionnaire was administered and venous blood was tested using HIV-1/enzyme immunoassays, plasma HIV-1 RNA levels/bDNA and immunophenotyping/flow cytometry to determine the frequencies of CD4 and CD8 T cells expressing activation markers. The data analysis showed significant differences (p < 0.05) for immune parameters in individuals who were uninfected, albeit exposed to HIV-infected partners, compared with unexposed individuals. In particular, the exposed, uninfected individuals had a higher frequency (median, minimum-maximum) of CD4⁺HLA-DR⁺ (4.2, 1.8-6.1), CD8⁺HLA-DR⁺ (4.6, 0.9-13.7), CD4⁺CD45RO⁺ (27.5, 14.2-46.6), CD4⁺CD45RO⁺CD62L⁺ (46.7, 33.9-67.1), CD8⁺CD45RA⁺HLA-DR⁺ (12.1, 3.4-35.8) and CD8⁺CD45RO⁺HLA-DR⁺ (9.0, 3.2-14.8) cells, a decreased percentage of CD8⁺CD28⁺ cells (11.7, 4.5-24.0) and a lower cell-surface expression of Fcγ-R/CD16 on monocytes (56.5, 22.0-130.0). The plasma HIV-1 RNA levels demonstrated detectable RNA virus loads in 57% of the HIV-1⁺ female partners. These findings demonstrate an activation profile in both CD4 and CD8 peripheral T cells from HIV-1 exposed seronegative individuals of serodiscordant couples from a referral centre in Belo Horizonte, state of Minas Gerais.

Background: Darunavir has been proven efficacious for antiretroviral-experienced HIV-1-infected patients in randomized trials. However, effectiveness of darunavir-based salvage therapy is understudied in routine care in Brazil., Methods: Retrospective cohort study of HIV-1-infected patients from three public referral centers in Belo Horizonte, who received a darunavir-based therapy between 2008 and 2010, after virologic failure. Primary endpoint was the proportion of patients with viral load<50 copies/mL at week 48. Change in CD4 cell count was also evaluated. Outcome measures were analyzed on an intent-to-treat basis applied to observational studies. Sensitivity analysis was conducted to evaluate the impact of missing data at week 48. Predictors of virologic failure were examined using rare-event, finite sample, bias-corrected logistic regression., Results: Among 108 patients, the median age was 44.2 years, and 72.2% were male. They had long-standing HIV-1 infection (median 11.6 years) and advanced disease (76.9% had an AIDS-defining event). All patients had previously received protease inhibitors and nucleoside reverse transcriptase inhibitors, 75% nonnucleoside reverse transcriptase inhibitors, and 4.6% enfuvirtide. The median length of protease inhibitor use was 8.9 years, and 90.8% of patients had prior exposure to unboosted protease inhibitor. Genotypic resistance profile showed a median of three primary protease inhibitor mutations and 10.2% had three or more darunavir resistance-associated mutations. Virologic success at week 48 was achieved by 78.7% (95% CI=69.7-86%) of patients and mean CD4 cell count increase from baseline was 131.5 cells/μL (95% CI=103.4-159.6). In multiple logistic regression analysis, higher baseline viral load (RR=1.04 per 10,000 copies/mL increase; 95% CI=1.01-1.09) and higher number of darunavir resistance-associated mutations (RR=1.23 per each; 95% CI=0.95-1.48) were independently associated with virologic failure., Conclusion: Virologic suppression is a realistic endpoint for most treatment-experienced patients who begin a darunavir-based therapy outside the controlled conditions of a randomized trial, at routine care settings., (Copyright © 2013 Elsevier Editora Ltda. All rights reserved.)

Introduction: Published data addressing the effectiveness of darunavir-ritonavir (DRV/r)-based therapy for multiexperienced patients in developing countries are scarce. This study evaluated the 48-week virologic and immunologic effectiveness of salvage therapy based on DRV/r for the treatment of multidrug-experienced HIV-1-infected adults in Brazil., Materials and Methods: A multicenter retrospective cohort study was carried out with multidrug-experienced adults who were on a failing antiretroviral therapy and started a DRV/r-based salvage therapy between 2008 and 2010. The primary effectiveness end point was the proportion of patients with virologic success (plasma HIV-1 RNA <50 copies/mL at week 48)., Results: At 48 weeks, 73% of the patients had HIV-RNA <50 copies/mL and a mean increase of 108 CD4 cells/mm(3). Higher baseline viral load, lower baseline CD4 count, younger age, and 3 or more DRV/r-associated resistance mutations were significantly predictive of virologic failure. Concomitant use of raltegravir was strongly associated with virologic success., Conclusion: The use of DRV/r-based regimens for salvage therapy is an effective strategy in the clinical care setting of a developing country.

The presence of transmitted human immunodeficiency virus (HIV)-1 drug-resistance (TDR) at the time of antiretroviral therapy initiation is associated with failure to achieve viral load (VL) suppression. Here, we report TDR surveillance in a specific population of men who have sex with men (MSM) in Belo Horizonte, Brazil. In this study, the rate of TDR was evaluated in 64 HIV-infected individuals from a cohort of MSM between 1996-June 2012. Fifty-four percent had a documented recent HIV infection, with a seroconversion time of less than 12 months. The median CD4+T lymphocyte count and VL were 531 cells/mm3 and 17,746 copies/mL, respectively. Considering the surveillance drug resistance mutation criteria, nine (14.1%) patients presented TDR, of which three (4.7%), five (7.8%) and four (6.2%) had protease inhibitors, resistant against nucleos(t)ide transcriptase inhibitors and against non-nucleoside reverse-transcriptase inhibitors mutations, respectively. Two of the patients had multi-drug-resistant HIV-1. The most prevalent viral subtype was B (44, 68.8%), followed by subtype F (11, 17.2%). This study shows that TDR may vary according to the population studied and it may be higher in clusters of MSM.

Objectives: The aim of this study was to learn more about people diagnosed with acquired immunodeficiency syndrome (AIDS) at age 60 and above in Brazil, and to compare them with people diagnosed at a younger age., Methods: This study was based on the analysis of secondary data from the Brazilian AIDS Program. The study population consisted of people diagnosed with AIDS at age 60 and above. The comparison group was comprised of a 20% random sample of people diagnosed at age 18 to 59, frequency-matched by year of diagnosis., Results: 544,846 cases of AIDS were reported in Brazil from 1980 until June 2009. Over 90% of cases were diagnosed between 18 and 59 years of age, and 13,657 (2.5%) at age 60 and above. The first case of AIDS among the elderly was reported in 1984. The comparison group consisted of 101,528 patients. Gender proportion was similar for both groups, and the proportion of people identified with AIDS after death in the Brazilian Mortality Information System (SIM) was 4% higher among the elderly. Both groups were also similar regarding the region of residence; a markedly higher proportion lived in Southeastern Brazil. Older people were more likely to have lower education and to have contracted AIDS by heterosexual contact, and less likely to be intravenous drug users. Male to female ratio among those diagnosed with AIDS at or above age 60 decreased over the years, in the same way as observed for the whole cohort. Mortality was higher among men in both groups. CD4 category (taken closest to the date of AIDS diagnosis) was very similar in both groups., Conclusion: The characteristics of the epidemic among the elderly show similarities to the younger group considering gender distribution and CD4 category, but differ regarding educational level and exposure category. Also, the elderly were more likely not to have their AIDS condition promptly diagnosed., (Copyright © 2012 Elsevier Editora Ltda. All rights reserved.)

The purpose of this study is to estimate the survival probability of patients following their first admission for the treatment of AIDS to an infectious disease reference hospital in Belo Horizonte, Brazil, during 2005. Study subjects were monitored during a 12-month period to identify factors associated with survival probability. Late diagnosis was recorded among many of the 250 study subjects: almost half (44.8%) were diagnosed less than 30 days prior to or during their hospitalization. A high mortality rate was also detected: 39.6% of the subjects died during the 12 months of monitoring. The cumulative survival probability of the cohort group was estimated at 68.0% after 3 months and at 61.2% after 12 months. However, certain patient subgroups analyzed had even lower cumulative survival probabilities after 12 months of monitoring: if diagnosed during hospitalization, it was estimated at only 48.0% and those with no record of antiretroviral treatment had a 48.5% cumulative survival probability. Patients with severe anemia had the lowest survival probability, similar among the two lymphocyte count groups (<1000 mm(3) and ≥1000 mm(3)), the former with a 45.5% survival probability and the latter with a 46.7% one. The proportional death risk was 2.5-fold higher for men residing in other area than the capital city of the State of Minas Gerais and greater metropolitan region when compared with women residing there. The findings of this study highlight the importance of early diagnosis for predicting patient survival and reinforce the necessity of facilitating HIV diagnosis.

Finding a better first antiretroviral regimen is one of the strategies used to improve span and quality of life of HIV/AIDS patients. 891 patients were followed during 24 months or until interruption/abandonment of treatment, changing regimen or death. At the end of 6 months, 69% of the patients were still being treated with the first regimen, 54% at 12 months, 48% at 18 months and 39% at 24 months. AZT-3TC-EFV was the most prescribed regimen and with the lesser discontinuation. NNRTI regimens showed high effectiveness and durability compared to PI regimens. Irregular medication dispensation was the only risk factor for failure/interruption of treatment in multivariate analyses. Intolerance/adverse effects were mainly responsible for first regimen discontinuation, followed by abandonment/non-adherence and virologic failure. Results showed significant difference between causes of interruption of first HAART with higher percentage of intolerance/adverse effects with PI regimens and higher immunologic failure with NNRTI regimens. Even with the availability of more potent and tolerable drugs, lack of adherence to HAART and high level of adverse effects are still the most important barriers to prolonged success of treatment. This study adds relevant information about durability and effectiveness of HAART in the first decade of its use in Brazil.

The emergence of resistance-associated mutations to the antiretroviral agents and the genetic variability of HIV-1 impose challenges to therapeutic success. We report the results of genotype testing assays performed between 2002 and 2006 in 240 antiretroviral-experienced patients followed up in an HIV reference center in Brazil. Drug resistance mutations and viral subtypes were assessed through the algorithms from the Brazilian Genotyping Network (RENAGENO-Brazil) and from Stanford University. Mutation 184VI was the most prevalent (70%) and the thymidine analogue mutations that appeared most frequently were 215FY, 41L, 67N, and 210W, in this order. Among nonnucleoside reverse transcriptase inhibitor mutations, 103NS (32.5%) stood out. HIV subtype B was identified in 184 patients (76.7%). A significant increasing trend in the prevalence of non-B subtypes was observed during the study period (p=0.004). The main differences in prevalence of mutations among HIV-1 subtypes were related to viral protease, with 20MRI, 36I, and 89IMT more prevalent among non-B subtypes, and 84V, 10FR, 63P, 71LTV, and 77I more common in subtype B (p<0.05). Most mutations to etravirine had a prevalence lower than 10%, but at least one mutation to this drug was observed in 45% of the patients. In only 11 patients (4.6%) three mutations to etravirine were verified. Regional surveillance of the resistance profile and HIV-1 subtypes is crucial in the context of public health, to prevent the transmission of resistant strains and to guide the introduction of new drugs in a specific population.

Nonnucleoside reverse transcriptase inhibitors (NNRTIs) are potent and well tolerated. In Brazil, the first-generation NNRTI efavirenz is included in the majority of first-line antiretroviral treatment regimens. In this study, we evaluated the effectiveness of etravirine, a new second-generation NNRTI, among patients failing antiretroviral regimens containing first-generation NNRTIs. We assessed single resistance mutations to etravirine as well as complex resistance mutations profile and discuss the potential of introducing etravirine as salvage therapy.

Conflicts of interest are inherent to the majority of relationships among individuals and of these with companies and institutions and, certainly, research involving human beings is no exception. In relation to clinical research, the main focus of this manuscript, conflicts of interest occur at different levels and usually permeate among them: In the pharmaceutical industry in their decisions to invest to develop new products, especially vaccines and drugs, and also in relation to marketing of these products; Among the investigators the conflicts may be related to the financial gains to participate in pharma sponsored trials, or to the expected academic career boost attained with the publication of the results of the trials and also to personal interests such as the financial support for trips to international conferences. Often the participation of host country investigators is restricted to performing phase III or IV protocols developed abroad, many times with low scientific relevance, and even lower relevance to public health; Universities or research institutes themselves also have conflicts of interest, as the sponsored projects may help increase their budgets, both directly (taxes) and indirectly (e.g., improvement of physical infrastructure of laboratories or out patient clinics); For the trial volunteers in developing countries, and Brazil is no exception despite free and universal access to its health system, participation in clinical trials is many times seen as, and can really be, an unique opportunity of receiving better health care, better treatment by the health professionals, easier access to costly lab exams and also to receiving certain medications which would otherwise be difficult to have access to. In order to handle these conflicts of interest, Brazil has a well-established and respected legal support and ethical normatization. The latter is represented by Resolution 196/96 of the Brazilian National Research Ethics Committee (CONEP). This national system was established in 1996 providing guidance to all research involving human beings and currently there are approximately 500 local research ethical committees certified by CONEP in all States of Brazil. However, there is intense international pressure mainly from the pharmaceutical industry especially to the ethical requirements emanated from the Declaration of Helsinki (DH), aiming to lower the level of ethical requirements in research to be carried out with volunteers from developing countries. Fallacious reasoning includes that the equity stated at the DH, especially the access to the best proven medical care and to the developed products to all volunteers independently of where the trial is being held, would inflate the costs of research and drive the sponsors away from the developing countries. In this line of thought, if the volunteers have not the same rights that would constitute an unacceptable double standard, or in other words, the best for the volunteers from developed countries and whatever is possible for those in developing countries. This manuscript will focus on the various levels where conflict of interest issues are more prone to happen, such as in the actions of pharmaceutical industries, their relation to health professionals, the participation of universities and research institutes, the ethical research committees and their members, including the possible pressures exerted on them by researchers, sponsors and even their institutions. Emphasis will be given to the interrelation between conflicts of interest and vulnerability, and also the causes and possible solutions to lower the risks of exploitation of volunteers in research. It will also emphasize the need to guarantee access to products that are proven efficacious to all individuals who may need them. Possible ways of empowering these volunteers will be evaluated, so that they become aware of their rights and demand for them. It will discuss the need of separating economic interests from the real needs of public health and of demystifying economic arguments used in order to justify the lowering of ethical requirements. And finally it will address the search for or the establishment of real and effective involvement of all stakeholders in an international organism really representing everyone (e.g., WHO) in order to evaluate, debate, and decrease the risks of several conflicts of interest, aiming at the establishment of research projects that can truly contribute to lower the obscene disparities of health between developed and developing countries.

We assessed the performance of HIV-1 genotyping tests in rescue therapy. Patients were divided into two groups: group 1 (genotyped), included those switching to new antiretroviral drugs based on HIV-1 genotyping data, and group 2 (standard of care -SOC), comprised those in rescue therapy who had not used this test. This was an open and non-randomized study, with 74 patients, followed up for a mean period of 12 months, from February 2002 to May 2003. The groups differed in the duration of antiretroviral use, experience with diverse drug classes (non-nucleoside reverse transcriptase inhibitors and protease inhibitors) and viral load <2.6 log10 copies/mL at any time during treatment. In 23 patients (group 1), the switch in antiretroviral (ARV) regimen was based on genotyping data; this test was not used for 51 patients (group 2). Two CD4 + lymphocyte counts and viral load counts were made for each patient during the study. Data from the pharmacy where patients received antiretroviral agents, medical charts, and direct interviews with patients to assess compliance to treatment, were analyzed. In the genotyped group, the average drop in viral load was 2.8 log10, compared with a 1.5 log10 difference in group 2; the difference was significant in the first assessment performed six months after switching (p=0.001). Considering the patients with viral load < 2.6 log10 (400 copies/mL) after switching, the patients in group 1 had a better performance in the first assessment (73.9% versus 31.1% in groups 1 and 2, respectively); this difference was significant (p=0.001). In multivariate analysis, the variables associated with a greater drop in viral load in the first assessment were the patients whose switching was based on genotyping (group 1), those with a past history of viral load < 2.6 log10 and correct use of antiretroviral agents. In conclusion, the genotyping test and adherence were found to be independent factors for success in the management of patients who failed treatment.

To study characteristics of neurological disorders in HIV/AIDS patients and their relationship to highly active antiretroviral treatment, a cross-sectional study was conducted in an infectious disease public hospital in Belo Horizonte, Brazil, between February 1999 and March 2000. Of the 417 patients enrolled, neurological disease was observed in 194 (46.5%) and a new AIDS-defining neurological event developed in 23.7% of individuals. Toxoplasmosis (42.3%), cryptococcosis meningitis (12.9%) and tuberculosis (10.8%) were the most common causes of neurological complications. The majority (79.3%) of patients were on highly active antiretroviral treatment and these individuals using HAART showed higher CD4 cell counts (p = 0.014) and presented stable neurological disease (p = 0.0001), although no difference was found with respect to the profile of neurological complications. The neurological diseases continue to be a frequent complication of HIV/AIDS and infections are still its main causes in Brazil, even in the highly active antiretroviral treatment era.

Human Ehrlichia chaffeensis infections have been reported in North America, Asia and Europe, but only recently have human cases been reported in Brazil. Nine new human cases of E. chaffeensis infection diagnosed on a clinical and serological basis are reported. Serological tests were performed with indoor slides prepared with CDC stock DH-82 cells infected with E. chaffeensis (Arkansas strain). All but two patients were adults. Seven patients were male and two female. The fever duration varied from 4 to 120 days with a median of 6 days. All patients recalled previous tick attack. IgM was detected in four cases. Influenza like syndrome was the most frequent clinical form affecting five patients. Two patients had fever of unknown origin (FUO), one patient had blood culture-negative endocarditis and one had encephalitis. All patients except one recovered. Two patients were correctly treated. One patient with FUO had AIDS and unexplained pancytopenia. The occurrence of human ehrlichiosis by E. chaffeensis remains to be proved in Brazil; the cases reported here highlight the possibility of such disease occurrence in Brazil.

Q fever has been considered non-existing in Brazil where reports of clinical cases still cannot be found. This case-series of 16 patients is a result of a systematic search for such illness by means of clinical and serologic criteria. Serologic testing was performed by the indirect microimmunofluorescence technique using phase I/II C. burnetii antigens. Influenza-like syndrome was the most frequent clinical form (eight cases--50%), followed by pneumonia, FUO (fever of unknown origin), mono-like syndrome (two cases--12.5% each), lymphadenitis (one case--6.3%) and spondylodiscitis associated with osteomyelitis (one case--6.3%). The ages varied from four to 67 years old with a median of 43.5. All but one patient had positive serologic tests for phase II IgG whether or not associated with IgM positivity compatible with acute infection. One patient had both phase I and phase II IgG antibodies compatible with chronic Q fever. Seroconvertion was detected in 10 patients. Despite the known limitations of serologic diagnosis, the cases here reported should encourage Brazilian doctors to include Q fever as an indigenous cause of febrile illness.

Rickettsial diseases except those belonging to spotted fever group rickettsioses are poorly studied in South America particularly in Brazil where few epidemiological reports have been published. We describe a serosurvey for Rickettsia rickettsii, R. typhi, Coxiella burnetii, Bartonella henselae, B. quintana, and Ehrlichia chaffeensis in 437 healthy people from a Brazilian rural community. The serum samples were tested by indirected micro-immunoflourescence technique and a cutoff titer of 1:64 was used. The seroprevalence rates for R. rickettsii, R. typhi, C. burnetii, B. henselae, B. quintana, and E. chaffeensis were respectively 1.6% (7 samples); 1.1% (5 samples); 3.9% (17 samples); 13.7% (60 samples); 12.8% (56 samples), and 10.5% (46 samples). Frequent multiple/cross-reactivity was observed in this study. Age over 40 years old, urban profession, and rural residence were significantly associated with some but not all infections rate. Low seropositivity rates for R. rickettsii, R. typhi, and C. burnetii contrasted with higher rates of seropositivity for B. quintana, B. henselae, and E. chaffeensis. These results show that all tested rickettsial species or antigenically closely related possible exist in this particular region.

Hepatitis B and C constitute important public health problems worldwide. In Brazil, studies on prevalence of viral hepatitis have local and regional characteristics; consequently it is difficult to define the national epidemiological situation. Our objective was to evaluate the seroprevalence of hepatitis B and C in conscripts of the Brazilian Army. A transversal study among males aged 17 to 22 years was conducted nationwide. After informed consent, each volunteer filled in a social-behavioral questionnaire and had blood drawn to test for HBsAg and anti-HCV. A total of 7,372 volunteers were evaluated in the second half of 2002. The prevalence of HBsAg was 2.6% (95% confidence interval: 2.2, 3.0) and that of anti-HCV was 1.5% (95% confidence interval: 1.2, 1.8). A wide variation among macro regions and states in the same region was observed for both markers. In conclusion, although this population theoretically had a low risk for HBV and HCV infection, these results are higher than expected for this age range. These findings may indicate a change in the pattern of HBV and HCV transmission in Brazil. Due to the different dynamics of these epidemics, further studies are warranted to confirm these apparent trends.

Passive surveillance of infectious diseases with a high percentage of asymptomatic cases or long incubation periods, such as acquired immunodeficiency syndrome (AIDS), does not reflect the current transmission dynamics. Thus, a multi-strategic surveillance, such as the human immunodeficiency virus (HIV) sentinel surveillance proposed by the World Health Organization (WHO), is necessary. The Brazilian HIV sentinel surveillance was started in May 1992 with this purpose. The objectives of this study were to evaluate the feasibility and costs of HIV and hepatitis C virus (HCV) surveillance using dried blood spots (DBS) collected for neonatal screening of metabolic diseases in the state of Minas Gerais, Brazil. This was accomplished through the comparison of HIV and HCV seroprevalence with previous Brazilian studies. From December 2001 to June 2002, 24,905 newborns were tested for HIV and 4211 for HCV. HIV seroprevalence was 0.25% and the 95% confidence interval (CI) was 0.18, 0.31%; and HCV seroprevalence was 0.71% and the 95% CI was 0.46, 0.97%. These numbers are similar to previous Brazilian studies. Cost in this study was approximately USD 3.10 per sample, which was roughly one third of the cost of the same exam at the Brazilian HIV sentinel surveillance. We conclude that it is possible and more cost-effective to use DBS for infectious diseases surveillance, albeit it is still necessary to compare these results with the usual sentinel methodology in a concomitant trial.

Project Horizonte, an open cohort of homosexual and bisexual human immunodeficiency virus (HIV-1) negative men, is a component of the AIDS Vaccine Program, in Belo Horizonte, Minas Gerais, Brazil. The objective of this study was to compare volunteers testing HIV positive at cohort entry with a sample of those who tested HIV negative in order to identify risk factors for prevalent HIV infection, in a population being screened for enrollment at Project Horizonte. A nested case-control study was conducted. HIV positive volunteers at entry (cases) were matched by age and admission date to three HIV negative controls each. Selected variables used for the current analysis included demographic factors, sexual behavior and other risk factors for HIV infection. During the study period (1994-2001), among the 621 volunteers screened, 61 tested positive for HIV. Cases were matched to 183 HIV negative control subjects. After adjustments, the main risk factors associated with HIV infection were unprotected sex with an occasional partners, OR = 3.7 (CI 95% 1.3-10.6), receptive anal intercourse with an occasional partner, OR = 2.8 (95% CI 0.9-8.9) and belonging to the negro racial group, OR = 3.4 (CI 95% 1.1-11.9). These variables were associated with an increase in the risk of HIV infection among men who have sex with men at the screening for admission to an open HIV negative cohort.