RICARDO DE PAULA VASCONCELOS
Projetos de Pesquisa
Unidades Organizacionais
LIM/52 - Laboratório de Virologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- Attitudes and Knowledge About Human Immunodeficiency Virus Pre-Exposure Prophylaxis Among Brazilian Infectious Disease Physicians(2020) CERQUEIRA, Natalia Barros; VASCONCELOS, Ricardo; HOJILLA, J. Carlo; KALLAS, Esper Georges; I, Vivian Avelino-SilvaThe objective was to describe levels and predictors of knowledge, attitudes, and willingness to prescribe pre-exposure prophylaxis (PrEP) among Brazilian Infectious Disease (ID) Physicians. The design was a cross-sectional study. We collected information on demographics and attitudes/knowledge about PrEP using an anonymous electronic survey. Willingness to prescribe PrEP, fear of adherence issues, and concerns about risk compensation were addressed in three case vignettes that varied by a single characteristic (i.e., by gender identity, drug use, and socioeconomic status) randomly assigned to physicians. Three hundred seventy ID physicians responded to the survey. Although most identified as informed/well informed about PrEP (75%) and believed PrEP availability to be necessary (38%), concerns with adherence (49%), side effects (38%), risk compensation (28%), and increase in sexually transmitted infection incidence (38%) were raised. We found no statistically significant differences in willingness to prescribe PrEP and concerns around risk compensation across the three case vignettes. ID physicians who declared having a religion reported more concerns about risk compensation compared to those self-identified as atheists (72% vs. 46%,p < .001). Most Brazilian ID physicians reported a positive attitude toward PrEP. Patients' gender identity, drug use, and socioeconomic status were not associated with willingness to prescribe PrEP. However, ID physicians who declared having a religion were more frequently concerned about risk compensation among PrEP users, suggesting that personal beliefs can influence PrEP implementation.
- Predictors of knowledge of and access to biomedical prevention among MSM and transgender men in Latin America: Results from the Latin American internet survey(2022) AVELINO-SILVA, Vivian Iida; VASCONCELOS, Ricardo; CERQUEIRA, Natalia B.; MARCUS, Ulrich; SCHMIDT, Axel Jeremias; VERAS, Maria AmeliaIntroduction HIV is still a central public health issue in Latin America, disproportionally affecting key populations. Knowledge and access to biomedical prevention strategies, including treatment as prevention (TASP) or undetectable = untransmissible (U=U), pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP), are the first steps to increasing uptake. We used data from the Latin American MSM Internet Survey (LAMIS) to describe knowledge and access to biomedical HIV prevention strategies among gay, bisexual, transgender and other men who have sex with men (MSM) living in 18 Latin American countries. Methods We compared LAMIS data across countries and according to age categories using frequencies and percentages. We also used multivariable models to explore whether age, gender identity, sexual identity, steady partnership, HIV status and education were independently associated with outcomes. Results In all, 55 924 participants were included. Most were cisgender (99%) and identified as gay/homosexual (77%) or bisexual (17%). Schooling levels were very high, with 89% reporting highest attained education as tertiary level, university or post-graduation. In total, 16% had been previously diagnosed with HIV; of those, rates of undetectable viral load varied from 60% in Venezuela to 83% in Brazil. Overall, 54%, 54% and 52% of participants already knew about PEP, PrEP and U=U, respectively. Participants from Brazil and those aged between 26 and 55 years, living with diagnosed HIV and having a gay/homosexual identity had greater levels of awareness about biomedical prevention strategies. Conclusions Our study highlights gaps in HIV prevention campaigns directed to MSM in Latin America resulting in low uptake of biomedical prevention methods.
- Asymptomatic anorectal Chlamydia trachomatis and Neisseria gonorrhoeae infections are associated with systemic CD8(+) T-cell activation(2017) VIEIRA, Vinicius A.; AVELINO-SILVA, Vivian I.; CERQUEIRA, Natalia B.; COSTA, Dayane A.; COSTA, Priscilla R.; VASCONCELOS, Ricardo P.; MADRUGA, Valdez R.; MOREIRA, Ronaldo I.; HOAGLAND, Brenda; VELOSO, Valdilea G.; GRINSZTEJN, Beatriz; KALLAS, Esper G.Background: Oral preexposure prophylaxis (PrEP) has been established as a pivotal strategy in HIV prevention. However, bacterial sexually transmitted infections (STIs), such as Chlamydia trachomatis and Neisseria gonorrhoeae, are also highly prevalent. Although the presence of STI-related mucosal lesions is a known risk factor for HIV acquisition, the potential increase in risk associated with asymptomatic STIs is not completely understood. Recent data demonstrated higher T-cell activation is a risk factor for sexually acquired HIV-1 infection. We examined the effect of asymptomatic C. trachomatis and N. gonorrhoeae anorectal infection on systemic immune activation, potentially increasing the risk of HIV acquisition. Methods: We analyzed samples from participants of PrEP Brasil, a demonstration study of daily oral emtricitabine/tenofovir disoproxil fumarate HIV PrEP among healthy MSM, for T-cell activation by flow cytometry. We included 34 asymptomatic participants with anorectal swab for C. trachomatis and/or N. gonorrhoeae infection, whereas negative for other STIs, and 35 controls. Results: We found a higher frequency of human leukocyte antigen DR(+)CD3(+)CD8(+)T cells (1.5 vs. 0.9%, P<0.005) and with memory phenotype in the group with asymptomatic C. trachomatis and/or N. gonorrhoeae infection. Exhaustion and senescence markers were also significant higher in this group. No difference was observed in the soluble CD14 levels. Conclusion: Our findings suggest asymptomatic anorectal C. trachomatis and/or N. gonorrhoeae increase systemic immune activation, potentially increasing the risk of HIV acquisition. Regular screening and treatment of asymptomatic STIs should be explored as adjuvant tools for HIV prevention.
- The Changing Epidemiology of Hepatitis C Virus Acquisition Among HIV-Infected Individuals in Brazil(2023) FERRUFINO, Rosario Quiroga; BIERRENBACH, Ana Luiza; RODRIGUES, Camila; FIGUEIREDO, Gerusa Maria; GLEISON, Daniel; YAPURA, Silvia; MATOS, Maria Laura Mariano de; VASCONCELOS, Ricardo; WITKIN, Steven Sol; MENDES-CORREA, Maria CassiaIdentification of mechanisms of hepatitis C virus (HCV) acquisition among HIV-infected people is critical for prevention guidance. The aim of this study was to investigate risk factors for HCV infection and variations in HCV genotype distribution in a cohort of HIV-HCV coinfected patients in Brazil. This was a cross-sectional observational epidemiological study of a cohort of HIV-HCV coinfected individuals seen at a referral center for HIV-infected patients in the city of Sao Paulo between January and December 2017. The time of HCV acquisition, as determined by chart review, was categorized as before 2000, between 2000 and 2009, and from 2010 onward. HCV genotypes were determined by gene amplification and analysis. Among 3,143 HIV-infected individuals analyzed, 362 (11.5%) were HCV-HIV coinfected. Overall, the reported modes of HCV acquisition were sexual exposure in 172 (47.5%), injection drug use (IDU) in 86 (23.8%), use of inhaled drugs in 67 (18.5%) and blood transfusion in 10 (2.8%) individuals. All individuals who acquired HCV after IDU became infected before 2010. HCV acquisition by sexual contact was reported by 26.4%, 65.9%, and 63.8% of patients before 2000, between 2000 and 2009, and from 2010, respectively. There was an increase (p < .001) in the proportion of cases due to sexual transmission from the period before 2000 (26.4%) to between 2000 and 2009 (65.9%). There was no corresponding increase from 2000 and 2009 to after 2010 (p = .751). HCV genotype 1 was most prevalent at all time periods. The genotype 3 frequency decreased over time (test for trend p < .001), whereas genotype 4, extremely uncommon before 2010, became the second most prevalent genotype from 2010 onward. In HIV-infected individuals in Sao Paulo, Brazil, sexual transmission has replaced IDU as the most frequent mode of HCV acquisition.
- Real-life occurrence of bacterial sexually transmitted infections among PrEP users: improving the diagnosis of Chlamydia trachomatis and Neisseria gonorrhoeae with multisite screening(2021) MOREIRA, Jorge Salomao; VASCONCELOS, Ricardo; DOI, Andre Mario; AVELINO-SILVA, Vivian IidaPrEP users are under high risk for bacterial sexually transmitted infections (STI), including those caused by Treponema pallidum (Tp), Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (Ng). Ct and Ng screening at multiple anatomic sites may improve the diagnostic sensitivity among high-risk populations. We analyzed the prevalence and incidence of Ct, Ng, and Tp and investigated predictors of bacterial STI occurrence between January 2018 and November 2019 in a retrospective cohort of PrEP users in Sao Paulo, Brazil. We describe the frequency and percentage of Ct/Ng per anatomical site and calculate the percentage of missed diagnosis if molecular testing were applied only in symptomatic patients, or only in urine samples. Patients underwent syphilis testing every 3-4 months and Ct/Ng testing every 6 months. We included 413 PrEP users with a median age of 31 years. At baseline, 25% had a positive treponemal test and 7% had active syphilis; Ct and Ng were more frequently detected in the oropharynx and anus (6.4-6.9%) than in urine samples (0.7-2.6%). Twelve months after the onset of PrEP, the incidence of Tp, Ct and Ng was, respectively, 13.4%, 11.4% and 8.9%. During follow-up, 23 out of 33 Ct/Ng cases (69%, 95% CI 51-84) would have been missed if oropharynx and anus samples had not been tested. In addition, if only symptomatic cases had been tested, 30 out of 33 Ct/Ng cases (90%, 95% CI 75-98) would have been missed. Participants with incident STI had a higher baseline number of sexual partners and a longer follow-up. Our study reinforces that active and frequent screening for STI is a powerful strategy to improve the diagnostic sensitivity.