Instituto Evandro Chagas

Objectives: To analyze the epidemiological profile of organ donations in the Northern Region of Brazil, from 2020 to 2024. Methods: Retrospective, quantitative, and epidemiological study, using secondary data from the Brazilian Association of Organ Transplantation (Associação Brasileira de Transplante de Órgãos). The variables [potential donors (PDs), actual donors (ADs), causes of death, gender, age group, interviews, and family refusal] were organized in a spreadsheet (Google Drive®) and analyzed using descriptive statistics (Microsoft Excel®), with the results presented in tables and graphs. Results: An increasing trend in potential and actual donors was observed, with heterogeneity among states. Male donors predominated in the 18-64 age group, and the main causes of death were traumatic brain injury and stroke. Interviews and family refusals increased during the period, with variation in the refusal rate. Conclusion: Family refusal, coupled with misinformation, was the main factor preventing organ donation. Structural, logistical, and professional training barriers contribute to regional inequalities, waiting lists, and organ shortages.

COVID-19 has caused substantial impacts on health, the economy, education, and quality of life worldwide, and pandemic control measures are directly associated with the quality of the pandemic response, which is essential for developing more assertive interventions for health promotion, treatment, and control of COVID-19. To evaluate epidemiological and operational indicators of COVID-19 surveillance in hospitalized patients in the state of Pará in 2021 by health mesoregion. A cross-sectional, analytical, and ecological epidemiological study. Data were obtained from the Epidemiological Surveillance of Severe Acute Respiratory Syndrome through the Influenza Epidemiological Surveillance System (SIVEP-Gripe). A total of 18,007 severe acute respiratory syndrome surveillance reports were included. In terms of incidence, there was a significant difference in the Lower Amazon, Southwest Pará, and Southeast Pará (p < 0.001). In terms of lethality, the highest rates were in the Lower Amazon and Metropolitan Region of Belém (p < 0.001). In terms of mortality, significance was observed in the Lower Amazon, the Metropolitan Region of Belém, and Southwest Pará (p < 0.001). For timely notification (80%), sample collection (80%), completion of the collection date (100%), recording of the molecular test date (100%), and Intensive Care Unit (ICU) admission (100%), none of the mesoregions reached the target. The criterion of confirmation, evolution, and date of evolution did not reach the target (100%) in any mesoregion. For timely case closure (80%), five mesoregions reached the goal: Lower Amazon, Marajó, Metropolitan Region of Belém, Northeast Pará, and Southeast Pará. Differences were observed between health mesoregions in both epidemiological and operational indicators. The most affected mesoregions were the Lower Amazon, Southwest Pará, and Southeast Pará, which have high social vulnerability and are farther from the metropolitan area of Belém, where health services with better hospital and laboratory structures are concentrated.

PurposeTo establish the first DRLs for contrast‐enhanced diagnostic pediatric fluoroscopic procedures in Brazil, stratified by body weight, based on data collected in a single tertiary referral public hospital of Rio de Janeiro city.MethodsThis descriptive, cross‐sectional study included 928 diagnostic fluoroscopy examinations performed in patients aged 0–18 years between December 2020 and December 2024 at a national pediatric referral center. Dosimetric parameters such as Air kerma‐area product (PKA), Air kerma at patient entrance reference point (Ka,r), fluoroscopy time, and number of images were extracted from automatically generated reports. Results were compared with existing international DRLs.ResultsLocal median doses showed overall agreement with European and UK reference levels in lower weight and age groups, but higher values were observed in patients with higher body mass. Compared with other single‐center studies, local KAP values were higher, likely reflecting differences in case complexity and exposure parameters. Weight‐based stratification proved more reliable than age‐based grouping for defining pediatric DRLs, supporting its use as the preferred reference criterion.ConclusionThis is the first Brazilian study to systematically report DRLs for diagnostic pediatric fluoroscopy using weight‐based stratification, that support the need for structured dose monitoring, protocol optimization, and continuous professional training.

This study investigates the evolutionary dynamics of norovirus GII.4 lineages circulating in the Amazon region of Brazil, with a particular focus on the recently emerged GII.4 San Francisco variant. A molecular descriptive design was employed, analyzing 615 stool samples from gastroenteritis patients collected between November 2023 and December 2024. Norovirus prevalence was 14.5%, with genotype characterization revealing a diverse array of circulating genotypes: GII·P31/GII.4, GII·P17/GII.17, GII·P16/GII.4, GII·P8/GII.8, GII·P7/GII.6, GII·P16/GII.10, and GII·P7/GII.7. Phylogenetic reconstruction and molecular clock analyses, performed using Bayesian inference in BEAST, demonstrated that Brazilian GII.4 strains are closely related to global lineages and highlighted rapid viral evolution, with a substitution rate of 2.28×10-4 substitutions/site/year. The GII.4 San Francisco variant, likely derived from the GII·P16/GII.4- Sydney_2012, was detected for the first time in Brazil, and a key recombination event was identified between the GII·P16 type and the GII.10 genotype. The research underscores substantial genetic diversity and ongoing evolution of norovirus in this region, emphasizing the necessity for continuous genomic surveillance to detect emerging variants and guide public health initiatives.

Health education has become an essential strategy for tackling preventable diseases within the context of the Brazilian Unified Health System (SUS). This article presents a narrative literature review to analyze how educational practices have been mobilized as an instrument of care and prevention, especially in territories marked by social vulnerabilities. National studies published in the last ten years were analyzed, with an emphasis on intersectoral experiences, participatory methodologies, and pedagogical devices aimed at health promotion. The findings were organized into two categories: (1) health education and the prevention of preventable diseases in the SUS and (2) interfaces between public policies, territories, and care. It was observed that educational practices planned and sensitive to local contexts contribute to strengthening primary care, empowering individuals, and promoting health equity. However, challenges such as policy discontinuity, insufficient professional training, and fragmentation of actions still persist. It is concluded that health education, beyond the transmission of information, should be understood as a dialogical, emancipatory, and intersectoral process, capable of generating transformations in the living and health conditions of the population.

Men who have sex with men (MSM) have been disproportionately affected by the human immunodeficiency virus (HIV) epidemic. The HIV treatment cascade is an important clinical monitoring strategy that involves the number of MSM living with HIV in health services. This study aimed to analyze the HIV treatment cascade in the MSM population in Brazil and to identify factors associated with different cascade stages. A cross-sectional study was conducted in 12 Brazilian capitals and included 4,176 MSM recruited through respondent-driven sampling in 2016. Factors associated with each stage of the HIV treatment cascade (outcomes), i.e., HIV diagnosis, use of antiretroviral therapy, and achievement of undetectable viral load, were identified via logistic regression. Approximately 18.3% (95% CI: 15.4–21.7) of the MSM were diagnosed with HIV at the time of the survey. Among those living with HIV, only 55.5% (95% CI: 46.2–64.4) had previous knowledge of their serologic status, and 98.4% (95% CI: 96.3–99.3) of those aware of their status used antiretroviral therapy. Among those reporting using antiretroviral therapy, 80.0% (95% CI: 64.8–89.7) had a suppressed viral load, whereas 79.4% (95% CI: 64.4–89.2) had an undetectable viral load. Age > 25 years, having completed high school or higher, having a previous diagnosis of another sexually transmitted infection, and not being identified as bisexual were positively associated with all outcomes. Once enrolled in HIV treatment programs, most MSM achieve viral suppression. The challenge for HIV control is that fully half of our sample or men who tested positive did not know their HIV status. Regardless of the reason for this lack of testing, Brazil faces a continuing HIV epidemic.

Diffusion MRI provides multiple quantitative descriptors of neural tissue derived from distinct physical and biophysical models, each probing different aspects of cerebral microstructure. While these metrics are often interpreted independently, their joint statistical structure may encode information about latent biophysical properties that constrain and organize brain microarchitecture. Here, we investigate whether stable patterns of multimodal diffusion MRI covariation reveal underlying biophysical diffusion properties of cerebral microstructure in the squirrel monkey (Saimiri sciureus). Using a high-resolution multimodal diffusion MRI dataset acquired at 11.7T (400 μm isotropic resolution) from 15 adult subjects, we analyzed tensor-based metrics alongside advanced multicompartment and axonal models, including NODDI and ActiveAx. Voxelwise and region-level correlation analyses were performed across multiple spatial scales to examine the structure, redundancy, and stability of relationships among diffusion-derived maps. We show that metrics originating from conceptually distinct models consistently organize into a low-dimensional structure characterized by stable clusters of covariation, robust to changes in parcellation and spatial aggregation. These patterns cannot be explained by trivial metric redundancy alone, but instead suggest convergence toward a reduced set of effective biophysical degrees of freedom governing diffusion behavior in neural tissue, including axonal organization, neurite density, orientation dispersion, and isotropic diffusion components. We interpret these covariation structures as manifestations of latent biophysical diffusion properties, emergent tissue states that are not directly observable through any single metric but become apparent through their structured relationships. From a systems neuroscience perspective, the stability of these latent dimensions supports the view that adult cerebral microstructure reflects the steady-state outcome of neurodevelopmental dynamics operating under biophysical constraints. Rather than providing a regional atlas, this work proposes a conceptual framework for interpreting multimodal diffusion MRI as a projection of an underlying low-dimensional biophysical state space organizing cerebral microstructure in primate brains.