Molecular detection and lineage differentiation of Trypanosoma cruzi in dogs from a metropolitan area of Central México: Implications for urban zoonotic transmission

Trypanosoma cruzi is the etiological agent of Chagas disease, a zoonotic infection that affects millions of people across the Americas. Despite its well-documented presence in rural and wild environments, little is known about its transmission dynamics in rapidly urbanizing areas. This study aimed to investigate the prevalence and genetic diversity of T. cruzi in domestic dogs from the Metropolitan Area of Querétaro, Mexico, a region where no formal studies of Chagas disease transmission have been conducted. A total of 303 canine blood samples were analyzed using PCR, and 5.9 % tested positive for T. cruzi. Lineage-specific PCR revealed that both TcI and TcII strains were present, suggesting complex transmission cycles potentially involving both wild and domestic reservoirs. These findings underscore the need for further research on vector ecology and the role of urban wildlife in maintaining T. cruzi transmission, highlighting an emerging risk for urban populations.