Análise temporal e aglomerados espaciais de elevado risco para a Doença de Chagas Aguda no Brasil: Estudo ecológico de base populacional

Abstract

Introduction: Chagas disease (CD) is an anthropozoonosis with a variable clinical presentation, which can be both asymptomatic and a disease capable of causing cardiomyopathy, gastrointestinal dysfunction, and other symptoms, often associated with significant morbidity and loss of quality of life, potentially leading to death. Despite its great relevance, there are still few studies that prove its true impact on Brazilian public health. Objective: To analyze the temporal trend and spatial distribution of notifications of acute Chagas disease (ACD) in Brazil, from January 2010 to December 2022, considering spatial clusters and their relationships with socioeconomic indicators. This is a population-based ecological study referring to all cases of ACD that occurred in Brazil between January 2010 and December 2022. Information on ACD cases was obtained from the Notifiable Diseases Information System (SINAN). Data on the Social Vulnerability Index was obtained from the Institute for Applied Economic Research (IPEA) and population data extracted from the 2010 census. For the temporal analysis, the Seasonal-Trend Model (STM) method was used, while for the spatial analysis, after mapping the incidence per 100,000 inhabitants with data from the Brazilian Institute of Geography and Statistics (IBGE), the municipalities were grouped and stratified, and the Global Moran Index was then calculated to identify spatial correlations, with the Local Spatial Association Index (LISA) used later to quantify the degree of spatial association. To evaluate the correlation between the variables and the Social Vulnerability Index (SVI), the Bivariate Global Moran statistic was used, with the subsequent bivariate LISA, which resulted in Moran dispersion diagrams identifying critical correlation areas. Results: During the study period, an increasing trend in the incidence of ACD was noted, with seasonality in the incidence of ACD between August and November, as well as statistically significant spatial dependence between some of the studied municipalities. At the same time, it was also found that municipalities with a high SVI were associated with higher ACD incidence rates and that, currently, the main form of transmission of ACD is the oral transmission route, which is strongly associated with the North region of Brazil. Conclusion: Despite the great advances in the control of CD in recent times, mainly in vector-borne transmission, the incidence of new cases of CD is currently on the rise, being strongly linked to social vulnerability, especially regarding poor urban infrastructure.