To analyse the completeness of the COVID-19 vaccination schedule and identify factors associated with vaccine uptake.

Cross-sectional study.

Data were collected through face-to-face interviews conducted in all 26 Brazilian state capitals and the Federal District between 2022 and 2023, using a sequential sampling approach.

A total of 1392 individuals aged 18 years or older experiencing homelessness for at least 6 months were included.

The primary outcome was the completeness of the COVID-19 vaccination schedule (complete vs incomplete), based on self-reported vaccination status. Secondary analyses examined sociodemographic, institutional and behavioural factors associated with vaccine uptake using binary logistic regression.

Completion of the vaccination schedule was positively associated with receiving government aid (OR: 1.58; 95% CI 1.09 to 2.30), visits from street clinic health agents (OR: 3.19; 95% CI 1.95 to 5.36), prior COVID-19 diagnosis (OR: 5.77; 95% CI 3.17 to 11.15), support for mandatory vaccination (OR: 3.76; 95% CI 2.48 to 5.76), trust in vaccine efficacy (OR: 3.92; 95% CI 2.63 to 5.89), seeking information from community sources (OR: 1.91; 95% CI 1.01 to 3.88) and trust in federal authorities (OR: 1.57; 95% CI 1.06 to 2.31).

This study identified structural, social and individual factors associated with complete COVID-19 vaccination among people experiencing homelessness in Brazil. Although overall coverage was substantial, gaps in vaccination completeness persisted. Social support, healthcare outreach and trust in vaccines were associated with higher uptake, highlighting important barriers and facilitators to vaccination in socially vulnerable populations.

Chagas disease affects millions of individuals across Latin America and imposes a substantial economic burden on healthcare systems, particularly in rural and underserved regions. Chronic Chagasic cardiomyopathy remains one of the leading causes of heart failure-related mortality in endemic countries. Tissue inhibitor of metalloproteinases-1 (TIMP-1) has emerged as a potential biomarker of myocardial fibrosis in cardiomyopathies. This study was designed to investigate the association between TIMP-1 and myocardial fibrosis in chronic Chagas disease and to assess its potential as an early biomarker of fibrotic remodelling.

Bottom of form: The PTICH trial is a single-centre, prospective observational cohort study conducted at a government reference clinic in Pernambuco, Brazil. The study aims to enrol 210 adults with Chagas heart disease: 140 without ventricular dysfunction (left ventricular ejection fraction (LVEF) ≥52% in women and ≥54% in men) and 70 with ventricular dysfunction (LVEF

The Research Ethics Committee (REC) of Chagas disease and heart failure outpatient clinic—PROCAPE approved the PTICH trial (CAAE number: 65746322.8.1001.5192). Written informed consent has been obtained from all participants enrolled to date, and data handling is in compliance with applicable privacy and data protection regulations. Study findings will be disseminated through targeted outreach to civil society, the scientific community, healthcare professionals and Brazilian Unified Health System (SUS) policymakers; school-based science communication activities conducted in collaboration with state education departments (potentially including oral health educational materials); policy briefs and targeted reports for public health managers; technical meetings and institutional presentations; a plain-language summary published on the institutional website; and submissions to peer-reviewed journals and presentations at academic and health policy conferences.

RBR-3dcrj98.

The interfaces between the fields of communication, education and health have been indicated by international institutions such as the WHO and the European Centre for Disease Prevention and Control. However, hegemonic scientific practices supersede dialogue between the three fields, isolating their practices. This fragmenting tendency is observed in scientific literature, which has created gaps in the dialogue and articulation between communication, education and health. Although health promotion requires both communicative and educational practices, the epistemological, historical, political, cultural and socioeconomic aspects have also engendered tensions between the fields. Communication is often seen as a mere instrument for other practices, rather than a phenomenon that (re)produces meanings and power dynamics. In opposing the reductionist and instrumentalising perspectives of knowledge fields, the primary objective of the scoping review is to map the scientific evidence on the interfaces between communication and education in health to indicate a conceptual framework that articulates communication and education practices within the context of health.

A transdisciplinary team developed this protocol based on the 2024 Joanna Briggs Institute Manual for Evidence Synthesis. The procedures required to conduct the review were guided by the frameworks proposed by Arksey and O'Malley, Levac et al and Peters et al. The study eligibility criteria were established based on the Problem, Concept and Context outlined in the research questions. Primary and secondary studies will be retrieved from nine sources, covering both conventional and grey literature. These sources include Embase, ERIC, LILACS, PubMed/MEDLINE, ScienceDirect, Scopus, Web of Science, the Brazilian Digital Library of Theses and Dissertations, and the Networked Digital Library of Theses and Dissertations. A categorised form will be used for data collection and subsequent analysis. The reporting of the review findings will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews.

The nature of the research and the use of secondary data sources do not require informed consent forms or approval from ethics committees in Brazil. The scientific findings from the review will be disseminated through peer-reviewed journals, academic conferences and other scientific communication channels.

The protocol was registered on the Open Science Framework (OSF) and is available at https://doi.org/10.17605/OSF.IO/Z3CX7.

SARS-CoV-2 infection provides protection against reinfection and severe COVID-19 disease; however, this protective effect may diminish over time. We assessed waning of natural immunity conferred by previous infection against severe disease and symptomatic reinfection in Brazil and Scotland.

We undertook a test-negative design study and nested case–control analysis to estimate waning of natural immunity against severe COVID-19 outcomes and symptomatic reinfection using national linked datasets. We used logistic regression to estimate ORs with 95% CIs. A stratified analysis assessed immunity during the Omicron dominant period in Brazil.

We included data from the adult populations of Brazil and Scotland from 1 June 2020 to 30 April 2022.

Severe COVID-19 was defined as hospitalisation or death. Reinfection was defined as reverse-transcriptase PCR or rapid antigen test confirmed at least 120 days after primary infection.

From Brazil, we included 30 881 873 tests and 1 301 665 severe COVID-19 outcomes, and from Scotland, we included 1 520 201 tests and 7988 severe COVID-19 outcomes. Against severe outcomes, sustained protection was observed for at least 12 months after primary SARS-CoV-2 infection with little evidence of waning: 12 months postprimary infection: Brazil OR 0.12 (95% CI 0.10 to 0.14), Scotland OR 0.03 (95% CI 0.02 to 0.04). For symptomatic reinfection, Brazilian data demonstrated evidence of waning in the 12 months following primary infection, although some residual protection remained beyond 12 months: 12 months postprimary infection: OR 0.42 (95% CI 0.40 to 0.43). The greatest reduction in risk of SARS-CoV-2 infection was in individuals with hybrid immunity (history of previous infection and vaccination), with sustained protection against severe outcomes at 12 months postprimary infection. During the Omicron dominant period in Brazil, odds of symptomatic reinfection were higher and increased more quickly over time when compared with the overall study period, although protection against severe outcomes was sustained at 12 months postprimary infection (whole study: OR 0.12 (95% CI 0.10 to 0.14); Omicron phase: OR 0.15 (95% CI 0.12 to 0.19)).

Cross-national analyses demonstrate sustained protection against severe COVID-19 disease for at least 12 months following natural SARS-CoV-2 infection, with vaccination further enhancing protection. Protection against symptomatic reinfection was lower with evidence of waning, but there remained a protective effect beyond 12 months from primary infection.