Scientists support the inclusion of the United States as an endemic country for Chagas disease

Scientists from the University of Florida, Texas A&M University, and the University of California have published an article proposing an official classification for the United States as a Chagas disease endemic country.

The Centers for Disease Control and Prevention (CDC) estimates that around 300,000 people in the United States are affected by Chagas disease, most of them undiagnosed and untreated. However, this estimation is mostly associated with people originally from Latin America, as the disease is often perceived as something foreign to the country, associated with travel-related issues in the media.

But the true incidence of Chagas disease remains unknown, as human Chagas disease is a notifiable disease in only 8 states (Arizona, Arkansas, Louisiana, Mississippi, Tennessee, Texas, Utah, and Washington) and two health jurisdictions in California (San Diego and Los Angeles).

However, Trypanosoma cruzi, the parasite that causes Chagas disease, has been around in the United States for a long time, even since prehistoric times, according to the experts. Since records have been kept, the first autochthonous case occurred in 1955, in a house infested with triatomine bugs. These insects, or “kissing bugs”, inhabit 32 states in the southern United States and, of the 11 species found, 9 have been discovered to carry the T.cruzi.

In recent years, efforts to detect people affected by Chagas disease have increased due to the continued reporting of cases since 2013. Between 2000 and 2018, 29 cases of autochthonous T. cruzi infection in humans have been confirmed in 8 states: California, Arizona, Texas, Tennessee, Louisiana, Missouri, Mississippi, and Arkansas; and the Texas Department of State Health has documented 50 probable and confirmed cases, either due to direct exposure to the vector or due to the lack of contact with Chagas disease–endemic areas of Latin America.

The prevalence of the vector in a population within a geographic area provides, in the opinion of the researchers, sufficient evidence to support the inclusion of the United States as a Chagas disease endemic country, more specifically, as “hypoendemic”, according to the definitions of the World Health Organization (WHO).

The United States has contributed 23.3% of global research on Chagas disease, but mostly focusing on drug development, diagnostics, and immunology. Acknowledging the endemic status of the country would also promote a better institutional response, and would help raise awareness of the risks, strengthening surveillance and increasing funding for research. All of this implies a broader understanding of epidemiology, aligned with a One Health approach.

Full Article: Chagas Disease, an Endemic Disease in the United States
Research article: Field evidence of Trypanosoma cruzi infection, diverse host use and invasion of human dwellings by the Chagas disease vector in Florida, USA (Beatty et al., 2025)