Evidence of likely autochthonous Chagas disease in the southwestern United States: A case series of Trypanosoma cruzi seropositive blood donors

Background: Chagas disease is a parasitic infection that can insidiously cause non-ischemic cardiomyopathy. Given the largely silent nature of this progressive disease, asymptomatic blood donors pose potential blood transfusion risk. Blood donation screening has become an unintentional form of Chagas disease surveillance, with thousands of new cases identified since national surveillance was initiated in 2007. Study Design and Methods: We recruited T. cruzi-positive blood donors identified from California and Arizona blood centers for confirmatory blood screening and assessment of lifetime infection risk. Results: Among eight suspected cases, we identified four confirmed US autochthonous infections. The current manuscript details the transmission sources, healthcare-seeking behaviors post-blood donation resulting, and clinical course of disease among persons without any history of travel to endemic Latin American countries. Discussion: This manuscript presents four additional US-acquired Chagas disease cases and identifies an opportunity for blood centers to assist in confronting barriers surrounding Chagas disease in the US.