Feasibility of dried blood spot for hepatitis C diagnosis in vulnerable subjects and people living in remote areas from Brazil.

BACKGROUND: Agile, accessible and cheap diagnosis of hepatitis C virus (HCV) infection is essential to achieve the elimination of this infection, worldwide, as mandated by the World Health Organzation as part of its strategy for 2030. Dried blood spots (DBS) can be an attractive alternative for sample collection among people living in remote areas and vulnerable populations due to the less invasive collection, its biosafety, and storage & transportation of samples at room temperature. DESIGN: This study aims to estimate the usefulness of dried blood spot samples for the diagnosis and the assessment of HCV infection rates in three different settings in Brazil. Cross-sectional analysis of a sample collection from different populations, aiming to assess the performance of the testing algorithms and respective procedures among different populations with diverse background infection rates. METHODS: We reported the evaluation of DBS as alternative samples for detecting anti-HCV in different groups in real life conditions: (I) Vulnerable subjects living in remote areas of Southeast, North and Northeast Brazil (n = 1464); (II) Beauticians (n = 288); (III) People who use non-injectable drugs (n = 201); (IV) patients referred to outpatient care (n = 275). RESULTS: General assay accuracy was 99%, with a weighted kappa value of 0.9, showing an excellent performance. Sensitivities ranged from 87.5% to 100.0% between groups and specificities were above 99.2%. A total of 194 individuals had HCV RNA in serum and concordance of anti-HCV detection in DBS was 98.4%. CONCLUSIONS: DBS samples could be used for anti-HCV detection in different populations recruited in real life conditions and ambulatory settings, with a high overall sensitivity and specificity.

Depression, Anxiety, and Lifestyle Among Essential Workers: A Web Survey From Brazil and Spain During the COVID-19 Pandemic.

BACKGROUND: Essential workers have been shown to present a higher prevalence of positive screenings for anxiety and depression during the COVID-19 pandemic. Individuals from countries with socioeconomic inequalities may be at increased risk for mental health disorders. OBJECTIVE: We aimed to assess the prevalence and predictors of depression, anxiety, and their comorbidity among essential workers in Brazil and Spain during the COVID-19 pandemic. METHODS: A web survey was conducted between April and May 2020 in both countries. The main outcome was a positive screening for depression only, anxiety only, or both. Lifestyle was measured using a lifestyle multidimensional scale adapted for the COVID-19 pandemic (Short Multidimensional Inventory Lifestyle Evaluation-Confinement). A multinomial logistic regression model was performed to evaluate the factors associated with depression, anxiety, and the presence of both conditions. RESULTS: From the 22,786 individuals included in the web survey, 3745 self-reported to be essential workers. Overall, 8.3% (n=311), 11.6% (n=434), and 27.4% (n=1027) presented positive screenings for depression, anxiety, and both, respectively. After adjusting for confounding factors, the multinomial model showed that an unhealthy lifestyle increased the likelihood of depression (adjusted odds ratio [AOR] 4.00, 95% CI 2.72-5.87), anxiety (AOR 2.39, 95% CI 1.80-3.20), and both anxiety and depression (AOR 8.30, 95% CI 5.90-11.7). Living in Brazil was associated with increased odds of depression (AOR 2.89, 95% CI 2.07-4.06), anxiety (AOR 2.81, 95%CI 2.11-3.74), and both conditions (AOR 5.99, 95% CI 4.53-7.91). CONCLUSIONS: Interventions addressing lifestyle may be useful in dealing with symptoms of common mental disorders during the strain imposed among essential workers by the COVID-19 pandemic. Essential workers who live in middle-income countries with higher rates of inequality may face additional challenges. Ensuring equitable treatment and support may be an important challenge ahead, considering the possible syndemic effect of the social determinants of health.

Utility of oral fluid samples for hepatitis B antibody detection in real life conditions.

BACKGROUND: Hepatitis B virus (HBV) testing in oral fluid samples may provide advantages in diagnosis, screening or prevalence studies, especially among individuals with venous access difficulties. This study aims to optimize one commercially available assay for detecting total anti-HBc marker in oral fluid samples and to evaluate its utility under real life conditions in different settings for the purposes of prevalence and diagnostic studies. METHODS: Oral fluid was collected using a Salivette device and some parameters were initially evaluated: type of elution buffer and sample volume. Thereafter, the utility of oral fluid samples for detection of anti-HBc was evaluated in real life conditions in which, 1296 individuals gave serum and oral fluid samples. All serum samples were submitted to commercial EIAs to detect total anti-HBc, according to the manufacturer's instructions and oral fluid samples according to previous optimization. RESULTS: In optimization evaluation, PBS/BSA 0.5% and 100 µL of oral fluid (volume was two-fold increased compared to serum in EIA) were chosen as transport buffer and sample volume. In the field study, anti-HBc was detected in 211 out of 1296 serum samples giving overall oral fluid sensitivity of 52.6% and specificity of 96%. Concordance was higher in ambulatory setting (67.7) compared to general population (31.8). Mean ± standard deviation values of optical density/cutoff (OD/CO) in serum samples were higher in false-negative oral fluid samples than those seen in true positive samples. Sensitivity was higher in those presenting active infection compared to anti-HBc isolate and past infection. Sensitivity also increased in the ambulatory group when HCV individuals were excluded. CONCLUSIONS: It was possible to optimize a commercial EIA for detecting anti-HBc in oral fluid samples and where the highest concordance was found in ambulatory settings and among individuals with active infection.

Housing characteristics of crack cocaine users in Northeast Brazil, 2011-2013. / Características de usuários de crack quanto à situação de moradia no Nordeste brasileiro, 2011-2013.

We compared sociodemographic characteristics, substance use patterns, sexual behavior, use of health services, and criminal records of homeless vs. domiciled users. Data are from the Brazilian National Survey on Crack Use. A discriminant model and correspondence analysis cross-compared characteristics of users according to their housing status. The logistic model revealed associations between "living in the streets" and female gender and intermittent work. "Homelessness" was also associated with the use of tobacco and "oxi" in the previous 30 days, reliance on soup kitchens, low access to public mental health services, and arrests in the previous year. Correspondence analysis highlighted the spatial proximity of the variables as follows: "having traded sex for drugs", "informal work", "age 31 years or older", "access to public mental health services", "problems with law enforcement", and female gender with homeless crack users. People who smoke crack cocaine in Northeast Brazil are seldom studied. Their profiles, stratified according to their housing conditions, show subgroups with specific characteristics. While domiciled users have access to specialized clinics, homeless users basically reported access to free food and harm reduction services.

Objetivou-se comparar características sociodemográficas, padrões de consumo de substâncias, comportamento sexual, utilização de serviços de saúde e envolvimento criminal de usuários, domiciliados e em situação de rua. Dados secundários do Inquérito Nacional sobre Uso do Crack, utilizando análise discriminante e de correspondência para comparar características dos usuários segundo condição de moradia. O modelo final de regressão logística evidenciou associações entre "situação de rua" e ser do sexo feminino, trabalho descontínuo, consumo de tabaco e "oxi" nos últimos 30 dias, uso de serviços de alimentação gratuita, baixo acesso a tratamento e frequentes detenções no último ano. Na análise de correspondência observou-se proximidade no espaço analítico de "troca de sexo por drogas", "trabalho informal", "idade" >31 anos, "baixo acesso a CAPS-ad", "problemas com a justiça criminal" e "sexo feminino" com os usuários de crack desabrigados. Pouco se sabe sobre usuários de crack em contexto na região Nordeste do Brasil. Os resultados evidenciam dois subgrupos com características específicas. Enquanto os domiciliados têm acesso aos serviços de CAPS-ad e outras clínicas especializadas, os usuários em situação de rua relataram, basicamente, acesso a serviços de alimentação gratuita e redução de danos.

Performance of HCV Antigen Testing for the Diagnosis and Monitoring of Antiviral Treatment: A Systematic Review and Meta-Analysis.

BACKGROUND AND AIMS: Active hepatitis C virus (HCV) infection is based on the detection of HCV RNA that it is effective but presents high cost and the need to hire trained personnel. This systematic review and meta-analysis is aimed at evaluating the diagnostic accuracy of HCV Ag testing to identify HCV cases and to monitor antiviral treatment including DAA treatment. METHODS: The studies were identified through a search in PubMed, Lilacs, and Scopus from 1990 through March 31, 2020. Cohort, cross-sectional, and randomized controlled trials were included. Two independent reviewers extracted data and assessed quality using an adapted Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Our primary outcome was to determine the accuracy of HCV Ag detection for the diagnosis, which we estimated using random-effects meta-analysis. RESULTS: Of 3,062 articles identified, 54 met our eligibility criteria. The studies described cohorts from 20 countries, including 14,286 individuals with chronic HCV individuals. Studies for ECLIA technology demonstrated highest quality compared to studies that used ELISA. The pooled sensitivity and specificity (95% CI) for HCV Ag detection of active HCV infection were 98.82% (95%CI = 98.04%; 99.30%) and 98.95% (95%CI = 97.84%; 99.49%), respectively. High concordance was found between HCV Ag testing and HCV RNA detection 89.7% and 95% to evaluate antiviral treatment. CONCLUSIONS: According to our findings, HCV Ag testing could be useful to identify HCV active cases in low-resource areas. For antiviral treatment, HCV Ag testing will be useful at the end of treatment.

Underage drinking in Brazil: findings from a community household survey.

OBJECTIVES: Previous studies have estimated the 30-day prevalence of alcohol use to be approximately 21% among youth in Brazil, despite the legal drinking age of 18 years. The present study aimed to determine the prevalence of underage drinking and its associated factors among adolescents in Brazil. METHODS: The 3rd National Survey on Drug Use by the Brazilian Population (III Levantamento Nacional sobre o Uso de Drogas pela População Brasileira) is a nationwide, multi-stage, probability-sample household survey. Herein, youth between the ages of 12-17 years were included. Lifetime and 12-month alcohol use prevalence were estimated. Factors associated with 12-month alcohol use were evaluated through multivariate analysis considering survey weights and design. RESULTS: Overall, 628 youth were interviewed. Estimated lifetime and 12-month alcohol use were 34.3% (standard error [SE] = 1.9) and 22.2% (SE = 1.7), respectively. Factors associated with 12-month drinking were: other/no religion vs. Christianity; living in rural vs. urban areas; self-reported diagnosis of depression vs. no self-reported depression; lifetime tobacco use vs. no history of tobacco use; and any illicit drug use vs. no history of illicit drug use. CONCLUSION: Considering that alcohol use is a major risk factor for early death among Brazilian youth, our findings highlight the importance of preventative measures to reduce underage drinking.

Lifestyle predictors of depression and anxiety during COVID-19: a machine learning approach.

INTRODUCTION: Recent research has suggested an increase in the global prevalence of psychiatric symptoms during the COVID-19 pandemic. This study aimed to assess whether lifestyle behaviors can predict the presence of depression and anxiety in the Brazilian general population, using a model developed in Spain. METHODS: A web survey was conducted during April-May 2020, which included the Short Multidimensional Inventory Lifestyle Evaluation (SMILE) scale, assessing lifestyle behaviors during the COVID-19 pandemic. Depression and anxiety were examined using the PHQ-2 and the GAD-7, respectively. Elastic net, random forest, and gradient tree boosting were used to develop predictive models. Each technique used a subset of the Spanish sample to train the models, which were then tested internally (vs. the remainder of the Spanish sample) and externally (vs. the full Brazilian sample), evaluating their effectiveness. RESULTS: The study sample included 22,562 individuals (19,069 from Brazil, and 3,493 from Spain). The models developed performed similarly and were equally effective in predicting depression and anxiety in both tests, with internal test AUC-ROC values of 0.85 (depression) and 0.86 (anxiety), and external test AUC-ROC values of 0.85 (depression) and 0.84 (anxiety). Meaning of life was the strongest predictor of depression, while sleep quality was the strongest predictor of anxiety during the COVID-19 epidemic. CONCLUSIONS: Specific lifestyle behaviors during the early COVID-19 epidemic successfully predicted the presence of depression and anxiety in a large Brazilian sample using machine learning models developed on a Spanish sample. Targeted interventions focused on promoting healthier lifestyles are encouraged.

Health inequalities in Rio de Janeiro, Brazil: lower healthy life expectancy in socioeconomically disadvantaged areas.

OBJECTIVES: We investigated deprivation and inequalities in life expectancy and healthy life expectancy by location in Rio de Janeiro, Brazil. METHODS: We conducted a health survey of 576 adults in 2006. Census tracts were stratified by income level and categorization as a slum. We determined health status by degree of functional limitation, according to the approach proposed by the World Health Organization. We calculated healthy life expectancies by Sullivan's method with abridged life table. RESULTS: We found the worst indicators in the slum stratum. The life expectancy at birth of men living in the richest parts of the city was 12.8 years longer than that of men living in deprived areas. For both men and women older than age 65 years, healthy life expectancy was more than twice as high in the richest sector as in the slum sector. CONCLUSIONS: Our analysis detailed the excess burden of poor health experienced by disadvantaged populations of Rio de Janeiro. Policy efforts are needed to reduce social inequalities in health in this city, especially among the elderly.

Dried blood spot sampling as an alternative for the improvement of hepatitis B and C diagnosis in key populations.

BACKGROUND: To achieve the elimination of hepatitis B and C, there is an urgent need to develop alternative strategies to increase the access of diagnosis, particularly among key populations such as people living with human immunodeficiency virus (HIV), individuals with coagulopathies and chronic kidney disease (CKD) patients. AIM: To evaluate the use of dried blood spot (DBS) in the detection of hepatitis B virus (HBV) and hepatitis C virus (HCV) markers. METHODS: A total of 430 individuals comprised of people living with HIV, coagulopathies and CKD provided paired serum and DBS samples. HBsAg, anti-HBc and anti-HCV were tested in those samples using a commercial electrochemiluminescence. Demographic and selected behavioral variables were evaluated to assess possible association with HBV and HCV positivity. RESULTS: Using DBS, HBsAg prevalence varied from 3.9% to 22.1%, anti-HBc rates varied from 25.5% to 45.6% and anti-HCV positivity ranged from 15.9% to 41.2% in key populations. Specificities of HBV and HCV tests using DBS varied from 88.9% to 100%. The HBsAg assay demonstrated the best performance in CKD and coagulopathy individuals and the anti-HCV test had a sensitivity and specificity of 100% in people living with HIV. Accuracy of HBV and HCV detection in DBS varied from 90.2% to 100%. In the CKD group, HBsAg positivity was associated with infrequent use of condoms, and anti-HBc positivity was associated with sharing nail cutters/razors/toothbrushes. Anti-HCV reactivity was positively associated with a history of transplantation and length of time using hemodialysis in both specimens. In people living with HIV, only the male gender was associated with anti-HBc positivity in serum and DBS. CONCLUSION: DBS with electrochemiluminescence are useful tools for the diagnosis and prevalence studies of hepatitis B and C among key populations and may increase the opportunity to foster prevention and treatment.

Evaluation of accuracy of hepatitis B virus antigen and antibody detection and relationship between epidemiological factors using dried blood spot.

Dried blood spots (DBS) testing might increase the access for Hepatitis B virus (HBV) diagnosis, but little is known about the performance of these assays in real life conditions. This study aims to evaluate the diagnostic accuracy of HBsAg, anti-HBc and anti-HBs detection in DBS in clinical settings and field studies and to evaluate demographic and risk behaviour according the presence of HBsAg and anti-HBc. Paired sera and DBS samples were obtained from 2309 individuals from 3 groups, defined as follows: G1: clinical setting (n = 5-19), G2: general population (n = 1305) and G3: vulnerable individuals that could be more exposed to blood contact (n = 485). Sera and DBS were tested using commercial enzyme immunoassay (EIA), with some modifications added. Using DBS samples, the specificity values were above 90 % for HBsAg and anti-HBc in all groups and for anti-HBs range from 58.6%-85%. HBsAg testing had the best performance in GI (sensitivity = 84.4 %) and among those samples that the paired serum also presented anti-HBc marker (sensitivity = 91.6 %). High sensitivity of anti-HBc testing in DBS samples was observed in GI (80.8 %) and among HBV active cases (HBsAg+/anti-HBc+) (98.4 %). Testing of anti-HBs in DBS showed the highest sensitivity in GIII (65.5 %), in previous HBV exposed and cured individuals and when serum titers were above 100 IU/mL (86.7 %). DBS samples could be used for screening and prevalence studies for HBsAg and anti-HBc, particularly in clinical settings and among HBV active cases in field studies.

The risks of HCV infection among Brazilian crack cocaine users: incorporating diagnostic test uncertainty.

Despite the initiative by WHO and other international organizations to eliminate HCV in the medium term, hepatitis C infection is still a major public health problem. Even non-injecting drugs users who engage in harmful or addictive drug use are at greater risk of acquiring the infection, when compared to the general population. This study evaluate risk factors for HCV infection in users of crack/cocaine in Brazil, using multilevel models that incorporate variations in the sensitivity and specificity of the respective diagnostic tests. The sample included all the participants of a national survey on street crack cocaine users with serologically reactive result in the rapid test for the HCV as well as 4 non-reactive controls, matched by sex, age category, and major geographic region of residence. Multilevel logistic regression models were used, with and without incorporation of the diagnostic test's sensitivity and specificity values. The odds of HCV infection were 85% higher among polydrug users, 7.81 times higher among injecting drug users, and 3.69 times higher in those reporting to have genital ulcers. Statistical modeling strategies that incorporate the sensitivity and specificity of diagnostic tests in challenging settings are useful for studying the association between risk factors and infection status.

Spatial spread of malaria and economic frontier expansion in the Brazilian Amazon.

The temporal and spatial evolution of malaria was described for the postfrontier phase of the Brazilian Amazon in 2003-2013. The current ecological study aimed to understand the relationship between spatial population mobility and the distribution of malaria cases. The study identified epidemiologically relevant areas using regional statistical modeling and spatial analyses that considered differential infections and types of work activities. Annual parasite incidence (API) in the region was highest in hotspots along the Amazon River and in the south and west settlement zone of Hiléia, with concentrations in environmental protection areas and açaí and Brazil nut extraction areas. The dispersal force decreased in the Central Amazon due to rapid urbanization and improved socioeconomic conditions for workers in consolidated settlement areas. The study characterized the spatial patterns of disease transmission according to the economic activity and regionalization of geographic areas, confirming that the incidence of infection by work activity and labor flow is linked to extractive activities and agricultural settlements.

Segurança dos profissionais de saúde que atuaram na linha de frente da pandemia por covid-19 no Brasil / Safety of health professionals who worked in the front line of the COVID-19 pandemic in Brazil / Seguridad de los profesionales de la salud que actuaron en primera línea de la pandemia de COVID-19 en Brasil

RESUMO: Objetivou-se avaliar a segurança dos profissionais de saúde que atuaram no combate à pandemia de covid-19 em 2020 nos serviços de saúde brasileiros. Realizou-se inquérito on line, conduzido entre junho e setembro de 2020, com profissionais de saúde de instituições públicas e privadas brasileiras, com base no questionário Health workers exposure risk assessment and management in the context of COVID-19 virus, da Organização Mundial de Saúde, sendo analisados 2.832 registros. Raça/cor e categoria profissional foram variáveis relacionadas ao aumento de casos de covid-19 dentre os profissionais. Os que se autodeclararam não brancos, técnicos e auxiliares de enfermagem tiveram chance maior de resultado positivo, indicando maior suscetibilidade à infecção relacionada ao nível socioeconômico e/ou categoria profissional e papel desempenhado no cuidado ao paciente. As variáveis estrutura das unidades de saúde, localização, teste e disponibilidade de equipamentos de proteção individual relacionaram-se ao grau de risco de contrair a doença. Ressalta-se a importância da garantia de insumos e equipamentos aos profissionais de saúde, sobretudo em um contexto pandêmico e entre aqueles com baixo nível socioeconômico que atuam na linha de frente. Riscos em situações de emergência e escassez devem ser prospectivamente monitorados, ajustando-se às iniciativas no tocante à segurança do paciente.

ABSTRACT: The objective of this study was to evaluate the safety of health professionals who worked in the fight against the COVID-19 pandemic in 2020 in Brazilian health services. An online survey was conducted between June and September 2020, with health professionals from Brazilian public and private institutions, based on the Health workers exposure risk assessment and management in the context of COVID-19 virus, from the World Health Organization, and 2,832 records were analyzed. Race/color and professional category were variables related to the increase of covid-19 cases among professionals. Those who self-declared themselves non-white, technical and nursing assistants had a higher chance of positive results, indicating a higher susceptibility to infection related to socioeconomic level and/or professional category and a role played in patient care. The variables structure of the health units, location, test and availability of personal protective equipment were related to the degree of risk of contracting the disease. The importance of ensuring inputs and equipment to health professionals is highlighted, especially in a pandemic context and among those with low socioeconomic level who work on the front line. Risks in emergency and scarcity situations should be prospectively monitored, adjusting to patient safety initiatives.

RESUMEN: El objetivo de este estudio fue evaluar la seguridad de los profesionales de la salud que actuaron en la lucha contra la pandemia de COVID-19 en 2020 en los servicios de salud brasileños. Entre junio y septiembre de 2020 se realizó una encuesta en línea con profesionales de la salud de instituciones públicas y privadas brasileñas, basada en la evaluación y gestión del riesgo de exposición de los trabajadores de la salud en el contexto del virus COVID-19, de la Organización Mundial de la Salud, y se analizaron 2.832 registros. Raza/color y categoría profesional fueron variables relacionadas con el aumento de casos de COVID-19 entre profesionales. Los que se autodeclararon no blancos, técnicos y auxiliares de enfermería tuvieron una mayor probabilidad de resultados positivos, lo que indica una mayor susceptibilidad a la infección relacionada con el nivel socioeconómico y/o categoría profesional y un papel desempeñado en la atención al paciente. Las variables estructura de las unidades de salud, ubicación, prueba y disponibilidad de equipo de protección personal se relacionaron con el grado de riesgo de contraer la enfermedad. Se destaca la importancia de garantizar insumos y equipos a los profesionales de la salud, especialmente en un contexto pandémico y entre aquellos con bajo nivel socioeconómico que trabajan en primera línea. Los riesgos en situaciones de emergencia y escasez deben ser monitoreados prospectivamente, ajustándose a las iniciativas de seguridad del paciente.

Correspondence analysis: a method for classifying similar patterns of violence against women.

Violence against women has received relatively little debate in society. It includes physical, psychological, and sexual abuse that jeopardizes the victim's health. Multivariate correspondence analysis and cluster analysis were applied to crimes reported to the Integrated Women's Aid Center in Rio de Janeiro, Brazil, to investigate associations between injury and define criteria for classifying the aggressions. Three groups of abuse were identified, differing according to the nature (physical, psychological, or sexual) and severity of the crimes. Less serious crimes consisted of threats and moderate physical injuries. The intermediate severity group included serious physical assault and threats. More serious crimes included death threats, rape, and sexual assault. The method thus allowed classification of the crimes in three groups according to severity.

Inequalities in HAART uptake and differential survival according to exposure category in Rio de Janeiro, Brazil.

Despite substantial improvement in prognosis and quality of life among people living with HIV/AIDS (PLWHA) in Brazil, inequalities in access to treatment remain. We assessed the impact of these inequalities on survival in Rio de Janeiro over a 12-year period (2000/11). Data were merged from four databases that comprise the national AIDS monitoring system: SINAN-AIDS (Brazilian Information System for Notificable Diseases; AIDS cases), SISCEL (laboratory tests), SICLOM (electronic dispensing system), and SIM (Brazilian Mortality Information System), using probabilistic linkage. Cox regressions were fitted to assess the impact of HAART (highly active antiretroviral therapy) on AIDS-related mortality among men who have sex with men (MSM), people who inject drugs (PWID), and heterosexuals diagnosed with AIDS, between 2000 and 2011, in the city of Rio de Janeiro, RJ, Brazil. Among 15,420 cases, 60.7% were heterosexuals, 36.1% MSM and 3.2% PWID. There were 2,807 (18.2%) deaths and the median survival time was 6.29. HAART and CD4+ > 200 at baseline were associated with important protective effects. Non-whites had a 33% higher risk of dying in consequence of AIDS than whites. PWID had a 56% higher risk and MSM a 11% lower risk of dying of AIDS than heterosexuals. Non-white individuals, those with less than eight years of formal education, and PWID, were more likely to die of AIDS and less likely to receive HAART. Important inequalities persist in access to treatment, resulting in disparate impacts on mortality among exposure categories. Despite these persistent disparities, mortality decreased significantly during the period for all categories under analysis, and the overall positive impact of HAART on survival has been dramatic.

HIV, HCV, HBV, and syphilis among transgender women from Brazil: Assessing different methods to adjust infection rates of a hard-to-reach, sparse population.

Different sampling strategies, analytic alternatives, and estimators have been proposed to better assess the characteristics of different hard-to-reach populations and their respective infection rates (as well as their sociodemographic characteristics, associated harms, and needs) in the context of studies based on respondent-driven sampling (RDS). Despite several methodological advances and hundreds of empirical studies implemented worldwide, some inchoate findings and methodological challenges remain. The in-depth assessment of the local structure of networks and the performance of the available estimators are particularly relevant when the target populations are sparse and highly stigmatized. In such populations, bottlenecks as well as other sources of biases (for instance, due to homophily and/or too sparse or fragmented groups of individuals) may be frequent, affecting the estimates.In the present study, data were derived from a cross-sectional, multicity RDS study, carried out in 12 Brazilian cities with transgender women (TGW). Overall, infection rates for HIV and syphilis were very high, with some variation between different cities. Notwithstanding, findings are of great concern, considering the fact that female TGW are not only very hard-to-reach but also face deeply-entrenched prejudice and have been out of the reach of most therapeutic and preventive programs and projects.We cross-compared findings adjusted using 2 estimators (the classic estimator usually known as estimator II, originally proposed by Volz and Heckathorn) and a brand new strategy to adjust data generated by RDS, partially based on Bayesian statistics, called for the sake of this paper, the RDS-B estimator. Adjusted prevalence was cross-compared with estimates generated by non-weighted analyses, using what has been called by us a naïve estimator or rough estimates.

Cross-sectional study to determine viral hepatitis knowledge in different urban populations in Brazil.

AIM: To evaluate viral hepatitis knowledge among individuals from different resource areas and health conditions to identify possible gaps. METHODS: A cross-sectional, descriptive study was carried out among 447 individuals from five distinct populations in Brazil: Southeast Viral Hepatitis Ambulatory (n = 100), South (n = 89) and Northeast (n = 114) Health Center, Southeast (n = 77) and Northeast (n = 67) low resource areas. All individuals answered a questionnaire assessing sociodemographic characteristics and viral hepatitis awareness. The perception was scored based on the average number of correct answers of all participants and categorized as "low" (0-28 correct answers) or "desirable" (29-46 correct answers). Associations between sociodemographic characteristics and perception were also evaluated. RESULTS: A low level of knowledge was observed in individuals from Northeast Health Center, Northeast and Southeast low resource areas while desirable knowledge was observed in individuals from Viral Hepatitis Ambulatory and South Health Center. According to sociodemographic characteristics, desirable scores were more common among those with secondary education (47.1%), those who declared themselves as white (46.3%), and those who lived in houses with three individuals (25.5%). Multivariate analysis showed an association between viral hepatitis perception and type of population. CONCLUSION: The results demonstrated high level of knowledge among study participants from health clinics from the Southeast region of Brazil and the importance of education programs in increasing the level of knowledge in low resource areas.

Características de usuários de crack quanto à situação de moradia no Nordeste brasileiro, 2011-2013 / Housing characteristics of crack cocaine users in Northeast Brazil, 2011-2013

Resumo Objetivou-se comparar características sociodemográficas, padrões de consumo de substâncias, comportamento sexual, utilização de serviços de saúde e envolvimento criminal de usuários, domiciliados e em situação de rua. Dados secundários do Inquérito Nacional sobre Uso do Crack, utilizando análise discriminante e de correspondência para comparar características dos usuários segundo condição de moradia. O modelo final de regressão logística evidenciou associações entre "situação de rua" e ser do sexo feminino, trabalho descontínuo, consumo de tabaco e "oxi" nos últimos 30 dias, uso de serviços de alimentação gratuita, baixo acesso a tratamento e frequentes detenções no último ano. Na análise de correspondência observou-se proximidade no espaço analítico de "troca de sexo por drogas", "trabalho informal", "idade" >31 anos, "baixo acesso a CAPS-ad", "problemas com a justiça criminal" e "sexo feminino" com os usuários de crack desabrigados. Pouco se sabe sobre usuários de crack em contexto na região Nordeste do Brasil. Os resultados evidenciam dois subgrupos com características específicas. Enquanto os domiciliados têm acesso aos serviços de CAPS-ad e outras clínicas especializadas, os usuários em situação de rua relataram, basicamente, acesso a serviços de alimentação gratuita e redução de danos.

Abstract We compared sociodemographic characteristics, substance use patterns, sexual behavior, use of health services, and criminal records of homeless vs. domiciled users. Data are from the Brazilian National Survey on Crack Use. A discriminant model and correspondence analysis cross-compared characteristics of users according to their housing status. The logistic model revealed associations between "living in the streets" and female gender and intermittent work. "Homelessness" was also associated with the use of tobacco and "oxi" in the previous 30 days, reliance on soup kitchens, low access to public mental health services, and arrests in the previous year. Correspondence analysis highlighted the spatial proximity of the variables as follows: "having traded sex for drugs", "informal work", "age 31 years or older", "access to public mental health services", "problems with law enforcement", and female gender with homeless crack users. People who smoke crack cocaine in Northeast Brazil are seldom studied. Their profiles, stratified according to their housing conditions, show subgroups with specific characteristics. While domiciled users have access to specialized clinics, homeless users basically reported access to free food and harm reduction services.

Underage drinking in Brazil: findings from a community household survey

Objectives: Previous studies have estimated the 30-day prevalence of alcohol use to be approximately 21% among youth in Brazil, despite the legal drinking age of 18 years. The present study aimed to determine the prevalence of underage drinking and its associated factors among adolescents in Brazil. Methods: The 3rd National Survey on Drug Use by the Brazilian Population (III Levantamento Nacional sobre o Uso de Drogas pela População Brasileira) is a nationwide, multi-stage, probability-sample household survey. Herein, youth between the ages of 12-17 years were included. Lifetime and 12-month alcohol use prevalence were estimated. Factors associated with 12-month alcohol use were evaluated through multivariate analysis considering survey weights and design. Results: Overall, 628 youth were interviewed. Estimated lifetime and 12-month alcohol use were 34.3% (standard error [SE] = 1.9) and 22.2% (SE = 1.7), respectively. Factors associated with 12-month drinking were: other/no religion vs. Christianity; living in rural vs. urban areas; self-reported diagnosis of depression vs. no self-reported depression; lifetime tobacco use vs. no history of tobacco use; and any illicit drug use vs. no history of illicit drug use. Conclusion: Considering that alcohol use is a major risk factor for early death among Brazilian youth, our findings highlight the importance of preventative measures to reduce underage drinking.

Lifestyle predictors of depression and anxiety during COVID-19: a machine learning approach

Abstract Introduction Recent research has suggested an increase in the global prevalence of psychiatric symptoms during the COVID-19 pandemic. This study aimed to assess whether lifestyle behaviors can predict the presence of depression and anxiety in the Brazilian general population, using a model developed in Spain. Methods A web survey was conducted during April-May 2020, which included the Short Multidimensional Inventory Lifestyle Evaluation (SMILE) scale, assessing lifestyle behaviors during the COVID-19 pandemic. Depression and anxiety were examined using the PHQ-2 and the GAD-7, respectively. Elastic net, random forest, and gradient tree boosting were used to develop predictive models. Each technique used a subset of the Spanish sample to train the models, which were then tested internally (vs. the remainder of the Spanish sample) and externally (vs. the full Brazilian sample), evaluating their effectiveness. Results The study sample included 22,562 individuals (19,069 from Brazil, and 3,493 from Spain). The models developed performed similarly and were equally effective in predicting depression and anxiety in both tests, with internal test AUC-ROC values of 0.85 (depression) and 0.86 (anxiety), and external test AUC-ROC values of 0.85 (depression) and 0.84 (anxiety). Meaning of life was the strongest predictor of depression, while sleep quality was the strongest predictor of anxiety during the COVID-19 epidemic. Conclusions Specific lifestyle behaviors during the early COVID-19 epidemic successfully predicted the presence of depression and anxiety in a large Brazilian sample using machine learning models developed on a Spanish sample. Targeted interventions focused on promoting healthier lifestyles are encouraged.