Endemic potential of Chagas disease in the U.S. southwest: updated surveillance of infected Triatomines from the U.S.-Mexico border region.

Trypanosoma cruzi, the etiological agent of Chagas disease, is a vector-borne parasite traditionally associated with sylvatic environments. We investigated the prevalence of T. cruzi in triatomines collected from El Paso County, Texas, and southern New Mexico. Specimens were morphologically identified as Triatoma rubida and subjected to quantitative PCR for parasite detection. Molecular sequencing of satellite and microsatellite DNA targets was performed to confirm species identity and assess strain lineage. Infected vectors were collected from both sylvatic and urban locations, including Franklin Mountains State Park and residential areas in El Paso (TX) and Las Cruces (NM). Of the 26 triatomines tested, 88.5% were positive for T. cruzi, representing a significant increase compared to a previous regional study, which reported an infection rate of 63.3%. The high prevalence of T. cruzi-infected T. rubida, particularly in urban and peri-urban areas of El Paso and Las Cruces, underscores the increasing public health significance of Chagas disease along the U.S.-Mexico border. These findings highlight the urgent need for sustained vector surveillance, advanced molecular characterization, and focused public health interventions to reduce transmission risks and raise clinical awareness in affected regions.