Background: Brazil’s Unified Health System (Sistema Único de Saúde—SUS) has played a crucial role in reducing health disparities by providing universal and free healthcare to a diverse population. However, the COVID-19 pandemic exposed significant barriers to healthcare access among vulnerable groups, particularly due to the intersection of multiple vulnerabilities. This study aimed to examine how intersectionality—specifically sex/gender, race/ethnicity, and education level—has influenced inequalities in healthcare service utilization among vulnerable populations during the COVID-19 pandemic in Brazil. Methods: This cross-sectional study is part of the “COVID-19 Social Thermometer in Brazil” project, conducted between May 2022 and October 2023 in Brazil’s state capitals and the Federal District, focusing on populations considered socially vulnerable during the pandemic. Participants were selected using sequential sampling and completed a structured questionnaire. Statistical analyses—performed using Excel, RStudio (version 4.3.2), and ArcGIS—included sociodemographic profiling, the construction of the Jeopardy Index (a measure of social vulnerability), and binary logistic regression to explore associations between Jeopardy Index and healthcare service utilization. Results: 3406 participants, the majority were men (60%), aged 30 to 59 years (65.1%), and identified as Black or Brown (72.2%). Most participants were concentrated in the Northeast (26.6%) and North (22.3%) macroregions. A high reliance on public healthcare services (SUS) was observed, particularly in the Southeast (96%). According to the Jeopardy Index, the most socially vulnerable groups—such as women, transgender individuals, Black people, and those with no formal education—were significantly more likely to rely on SUS (OR = 3.14; 95% CI: 1.34–7.35) and less likely to use private healthcare (OR = 0.07; 95% CI: 0.02–0.20), reflecting a 214% higher likelihood of SUS use and a 93% lower likelihood of private service utilization compared to the most privileged group. Conclusions: Our findings reveal that individuals experiencing intersecting social vulnerabilities face marked inequalities in healthcare access. Without SUS, these populations would likely have been excluded from essential care. Strengthening SUS and implementing inclusive public policies are critical to reducing disparities and ensuring equitable healthcare access for historically marginalized groups.

In this study, the aim was to comparatively examine the perception of risk for developing severe illness or complications due to COVID-19 among the general population and socially vulnerable populations in Brazil, focusing on uncovering the associated factors that disproportionately impacted people experiencing homelessness and slum dwellers. This study is part of the project “Social Thermometer—COVID-19 in Brazil”, which employed a hybrid approach, combining a national online survey with field research in state capitals and the Federal District. Data collection took place from August 2020 to October 2023, and the data were analyzed using descriptive statistics and logistic regression. A total of 5094 participants were included in this study, with 2363 from the general population and 2731 from the socially vulnerable population. Among the general population, the majority of participants were women, white individuals, those with higher incomes, formal employment, and higher education levels. Concerning the vulnerable population, most were men, Black individuals, those with lower incomes, unemployment, and lower education levels. It was observed that 87% of the general population perceived a risk of severe COVID-19, compared to 74% of the vulnerable population. Slum dwellers who received emergency aid (OR_a = 1.39; 95% CI: 1.02–1.91), adhered to mask-wearing practices (OR_a = 1.93; 95% CI: 1.39–2.66), used COVID-19-related medications (ORa = 2.13; 95% CI: 1.31–3. 64), and those with pre-existing conditions, such as high blood pressure (OR_a = 1.86; 95% CI: 1.20–2.98), demonstrated a heightened perception of risk for severe COVID-19 complications. Among the homeless population, individuals who wore masks (OR_a = 1.67; 95% CI: 1.26–2.20 and had been vaccinated (OR_a = 1.44; 95% CI: 1.04–1.98) were also more likely to perceive a high risk. In conclusion, in this study, significant disparities are revealed in the perception of COVID-19 risk between the general and socially vulnerable populations in Brazil. Factors such as receiving emergency aid, adherence to mask-wearing, use of COVID-19-related medications, and pre-existing health conditions were associated with increased risk perception. Despite facing greater socioeconomic challenges, vulnerable groups, particularly those experiencing homelessness and slum dwellers, showed a lower perception of the risk for severe COVID-19 complications.

Almost four years after COVID-19 was declared a global health emergency, equitable distribution of the vaccine remains a challenge, especially among homeless people, the fastest growing population in Brazil. Therefore, we sought to identify the factors associated with completion of the COVID-19 vaccination schedule among homeless people in Brazil. Materials and Methods: We carried out a cross-sectional study in the capital cities of Brazil's Federative Units, considering people living on the streets as the target population. We used a sequential inclusion approach, with individual interviews conducted by trained professionals, using a validated questionnaire. We used descriptive statistics to analyze the data and a binary logistic regression model to identify factors associated with homeless individuals who completed the COVID-19 vaccination schedule. Results: It was identified that the highest density of homeless people and indicators related to COVID-19 is located in the Northeast, Southeast and South regions of Brazil. The primary data sample consisted of 1,392 participants, predominantly male (n: 961; 69.0%), with an average age of 38.3±15.2 years, belonging to the black/brown race/color (n: 1,097; 78.8%), with an elementary school education (n: 1,060; 76.1%). The factors associated with completing the vaccination schedule were: receiving government aid (OR: 1.58; 95%CI: 1.09 - 2.30), visits from Health Agents from the Street Clinic (OR: 3.19; 95%CI: 1.95 - 5.36), history of COVID-19 (OR: 5.77; 95%CI: 3.17 - 11.15), support for mandatory vaccination against COVID-19 (OR: 3.76; 95%CI: 2.48 - 5.76), trust in the efficacy of vaccines (OR: 3.92; 95%CI: 2.63 - 5.89), seeking information from NGOs, street clinics, community leaders (OR: 1.91; 95%CI: 1.01 - 3.88) and trust in the Federal Government's statements on vaccines (OR: 1.57; 95%CI: 1.06 - 2.31).Conclusion: The study advances knowledge by highlighting the completeness of the COVID-19 vaccination schedule among the homeless population. The source of information proved to be one of the determinants of completeness, and the Unified Health System played a leading role in raising awareness among homeless people, notably through its strategy of street clinics, when available. The evidence points to the importance of affirmative and inclusive actions that guarantee access to the vaccine for homeless people.