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.

Frequent detection but lack of infectivity of SARS-CoV-2 RNA in pre-symptomatic, infected blood donor plasma

Respiratory viruses such as influenza do not typically cause viremia; however, SARS-CoV-2 has been detected in the blood of COVID-19 patients with mild and severe symptoms. Detection of SARS-CoV-2 in blood raises questions about its role in pathogenesis as well as transfusion safety concerns. Blood donor reports of symptoms or a diagnosis of COVID-19 after donation (post-donation information, PDI) preceded or coincided with increased general population COVID-19 mortality. Plasma samples from 2,250 blood donors who reported possible COVID-19–related PDI were tested for the presence of SARS-CoV-2 RNA. Detection of RNAemia peaked at 9%–15% of PDI donors in late 2020 to early 2021 and fell to approximately 4% after implementation of widespread vaccination in the population. RNAemic donors were 1.2- to 1.4-fold more likely to report cough or shortness of breath and 1.8-fold more likely to report change in taste or smell compared with infected donors without detectable RNAemia. No infectious virus was detected in plasma from RNAemic donors; inoculation of permissive cell lines produced less than 0.7–7 plaque-forming units (PFU)/mL and in susceptible mice less than 100 PFU/mL in RNA-positive plasma based on limits of detection in these models. These findings suggest that blood transfusions are highly unlikely to transmit SARS-CoV-2 infection.