Seroepidemiological survey and seropositivity rate for Trypanosoma cruzi infection in a community-based cardiac screening initiative in Feira de Santana, Bahia, Brazil

Abstract

Chagas disease (CD), caused by Trypanosoma cruzi, is a significant public health issue in Latin America, particularly in endemic regions. This study integrates a seroepidemiological survey with large-scale echocardiographic screening conducted in Feira de Santana, a highly endemic city in Bahia, Brazil, to estimate the seropositivity rate of T. cruzi infection and identify associated risk factors. Peripheral blood samples were analyzed using in-house ELISA based on IBMP chimeric antigens and an indirect hemagglutination assay. Among 1,115 participants enrolled in the cardiac screening initiative, 140 underwent serological testing comprising individuals who screened positive based on clinical data, conventional ECG, and ECG-AI, and controls matched in a 2:1 ratio. Of these, 8.5% tested seropositive, with household exposure to triatomines identified as the strongest risk factor (prevalence ratio = 4.38, p = 0.004). Most seropositive individuals were migrants from other endemic areas, underscoring the influence of population mobility on CD epidemiology. This study highlights the importance of integrating diagnostic tools and vector control strategies into community-based health initiatives to improve early detection, reduce disease burden, and inform public health interventions in underserved regions.