Prevalence analysis of Chagas disease by age group in an endemic region of Brazil: possible scenario of active vectorial transmission.

Objectives: Chagas disease (CD) is an infectious disease that predominantly affects poor and vulnerable populations. The last estimate conducted by the World Health Organization in Latin America regarding the prevalence of CD occurred more than 10 years ago. However, there is a scarcity of data assessing the magnitude of CD in populations residing in considered high-risk regions. Therefore, this study aimed to assess the seroprevalence of CD in an endemic region in Northern Minas Gerais through serologic screening. Methods: This is a prevalence study conducted in the municipalities of Catuti, Mato Verde, Mirabela, Montes Azul, and São Francisco, Minas Gerais, Brazil. Data collection occurred between December 2021 and December 2022, involving a questionnaire with closed-ended questions. The variables analyzed included serologic test results, stratified age groups, health indicators, and housing conditions. Results: Of the 2978 participants, 272 individuals (9.1%) tested positive for CD serology. In the age group of 4 to 14 years, 15 to 49 years, and 50 years or older, the prevalence of positive serology was 0.8% (95% confidence interval [CI] 0.16-1.43), 5.5% (95% CI 4.20-6.83), and 18.8% (95% CI 16.48-21.11), respectively. Among the participating municipalities, Mato Verde had the highest prevalence of positive serology for CD (17%). For participants aged 4 to 14 years with positive serology for CD, first-degree relatives were invited to undergo serologic testing. It was possible to collect samples from relatives of all participants in this age group. However, none of the relatives tested positive. Conclusion: This study identified a 9.1% prevalence of individuals affected by CD who were unaware of their condition. In addition, having infected children in the 4 to 14 age group with mothers with negative serology would rule out congenital transmission of the disease.

Association between positive serology for COVID-19 and chagas cardiomyopathy progression: The SaMi-Trop project.

BACKGROUND: Chagas Disease (CD) can cause Chagas cardiomyopathy. The new coronavirus disease (COVID-19) also affects the cardiovascular system and may worsen Chagas cardiomyopathy. However, the cardiac evolution of patients with CD infected by COVID-19 is not known. Thus, the objective of this study is to assess, within one year, whether there was cardiac progression after COVID-19 in CD. METHODS: Longitudinal study with CD patients. The outcome was cardiac progression, defined as the appearance of new major changes in the current ECG compared to the previous ECG considered from the comparison of electrocardiograms (ECGs) performed with an interval of one year. Positive Anti-SARS-CoV2 Serology was the independent variable of interest. For each analysis, a final multiple model was constructed, adjusted for sociodemographic, clinical, and pandemic-related characteristics. RESULTS: Of the 404 individuals included, 22.8 % had positive serology for COVID-19 and 10.9 % had cardiac progression. In the final model, positive serology for COVID-19 was the only factor associated with cardiac progression in the group as a whole (OR = 2.65; 95 % CI = 1.27-5.53) and for new-onset cardiomyopathy in the group with normal previous ECG (OR = 3.50; 95 % CI = 1.21-10.13). CONCLUSION: Our study shows an association between COVID-19 and progression of Chagas cardiomyopathy, evaluated by repeated ECGs, suggesting that COVID-19 accelerated the natural history of CD.

Contextual influence on poor self-rated health in patients with Chagas disease: multilevel study.

Chagas disease (CD) is recognized by the World Health Organization as one of the thirteen most neglected tropical diseases in the world. Self-perceived health is considered a better predictor of mortality than objective measures of health status, and the context in which one lives influences this predictor. This study aimed to evaluate the prevalence and individual and contextual factors associated with poor self-rated health among CD patients from an endemic region in Brazil. It is a multilevel cross-sectional study. The individual data come from a cross-section of a cohort study named SaMi-Trop. Contextual data was collected from publicly accessible institutional information systems and platforms. The dependent variable was self-perceived health. The analysis was performed using multilevel binary logistic regression. The study included 1,513 patients with CD, where 335 (22.1%) had Poor self-rated health. This study revealed the influence of the organization/offer of the Brazilian public health service and of individual characteristics on the self-perceived health of patients with CD.

Genome-wide association study for Chagas Cardiomyopathy identify a new risk locus on chromosome 18 associated with an immune-related protein and transcriptional signature.

BACKGROUND: Chronic Chagas Cardiomyopathy (CCC) usually develops between 10 and 20 years after the first parasitic infection and is one of the leading causes of end-stage heart failure in Latin America. Despite the great inter-individual variability in CCC susceptibility (only 30% of infected individuals ever present CCC), there are no known predictors for disease development in those chronically infected. METHODOLOGY/PRINCIPAL FINDINGS: We describe a new susceptibility locus for CCC through a GWAS analysis in the SaMi-Trop cohort, a population-based study conducted in a Chagas endemic region from Brazil. This locus was also associated with CCC in the REDS II Study. The newly identified locus (rs34238187, OR 0.73, p-value 2.03 x 10-9) spans a haplotype of approximately 30Kb on chromosome 18 (chr18: 5028302-5057621) and is also associated with 80 different traits, most of them blood protein traits significantly enriched for immune-related biological pathways. Hi-C data show that the newly associated locus is able to interact with chromatin sites as far as 10Mb on chromosome 18 in a number of different cell types and tissues. Finally, we were able to confirm, at the tissue transcriptional level, the immune-associated blood protein signature using a multi-tissue differential gene expression and enrichment analysis. CONCLUSIONS/SIGNIFICANCE: We suggest that the newly identified locus impacts CCC risk among T cruzi infected individuals through the modulation of a downstream transcriptional and protein signature associated with host-parasite immune response. Functional characterization of the novel risk locus is warranted.

Contextual influence on poor self-rated health in patients with Chagas disease: multilevel study / Influência contextual na pior autopercepção em saúde de portadores de Doença de Chagas: estudo multinível

Abstract Chagas disease (CD) is recognized by the World Health Organization as one of the thirteen most neglected tropical diseases in the world. Self-perceived health is considered a better predictor of mortality than objective measures of health status, and the context in which one lives influences this predictor. This study aimed to evaluate the prevalence and individual and contextual factors associated with poor self-rated health among CD patients from an endemic region in Brazil. It is a multilevel cross-sectional study. The individual data come from a cross-section of a cohort study named SaMi-Trop. Contextual data was collected from publicly accessible institutional information systems and platforms. The dependent variable was self-perceived health. The analysis was performed using multilevel binary logistic regression. The study included 1,513 patients with CD, where 335 (22.1%) had Poor self-rated health. This study revealed the influence of the organization/offer of the Brazilian public health service and of individual characteristics on the self-perceived health of patients with CD.

Resumo A Doença de Chagas (DC) é reconhecida pela Organização Mundial da Saúde como uma das treze doenças tropicais mais negligenciadas do mundo. A autopercepção de saúde é considerada um melhor preditor de mortalidade do que medidas objetivas do estado de saúde, e o contexto em que se vive influencia esse preditor. O objetivo deste estudo foi avaliar a prevalência e os fatores individuais e contextuais associados à pior autopercepção em saúde de pacientes com DC de uma região endêmica do Brasil. É um estudo transversal multinível. Os dados individuais vêm de um corte transversal de um estudo de coorte denominado SaMi-Trop. Os dados contextuais foram coletados a partir de plataformas e sistemas de informações institucionais acessíveis ao público. A variável dependente foi a autopercepção de saúde. A análise foi realizada por meio de regressão logística binária multinível. Participaram do estudo 1.513 pacientes com DC, sendo 335 (22,1%) com pior autopercepção de saúde. Este estudo revelou a influência da organização/oferta do serviço público de saúde brasileiro e de características individuais na autopercepção de saúde de pacientes com DC.