One Health Interactions of Chagas Disease Vectors, Canid Hosts, and Human Residents along the Texas-Mexico Border

Abstract

BackgroundChagas disease (Trypanosoma cruzi infection) is the leading cause of non-ischemic dilated cardiomyopathy in Latin America. Texas, particularly the southern region, has compounding factors that could contribute to T. cruzi transmission; however, epidemiologic studies are lacking. The aim of this study was to ascertain the prevalence of T. cruzi in three different mammalian species (coyotes, stray domestic dogs, and humans) and vectors (Triatoma species) to understand the burden of Chagas disease among sylvatic, peridomestic, and domestic cycles.Methodology/Principal FindingsTo determine prevalence of infection, we tested sera from coyotes, stray domestic dogs housed in public shelters, and residents participating in related research studies and found 8%, 3.8%, and 0.36% positive for T. cruzi, respectively. PCR was used to determine the prevalence of T. cruzi DNA in vectors collected in peridomestic locations in the region, with 56.5% testing positive for the parasite, further confirming risk of transmission in the region.Conclusions/SignificanceOur findings contribute to the growing body of evidence for autochthonous Chagas disease transmission in south Texas. Considering this region has a population of 1.3 million, and up to 30% of T. cruzi infected individuals developing severe cardiac disease, it is imperative that we identify high risk groups for surveillance and treatment purposes.

Seroprevalence for the tick-borne relapsing fever spirochete Borrelia turicatae among small and medium sized mammals of Texas

“…Shelter dogs and wild canids and raccoons were also sampled. Serum samples from stray domestic dogs located in Brownsville, TX were collected, as previously described [ 21 ]. Coyote, gray fox, and raccoon serum samples were collected as part of the Texas Department of State Health Services rabies surveillance program.…”

Prevalence and Seroprevalence of Trypanosoma cruzi Infection in a Military Population in Texas

“…Statistical modeling estimates that one case of vectorial transmission requires 900–4,000 contacts with an infected triatomine. 27 Second, triatomines opportunistically feed on a variety of vertebrate species—many of which are present on JBSA and have tested positive for T. cruzi infection in south-central Texas 28 , 29 —offering competitive, nonhuman blood meal sources. Third, species-specific vector competency may vary based on environmental distribution, flying and dispersal capacity, inclination to invade human dwellings, and feeding and defecation patterns.…”

“… 34 , 37 , 38 Risk for autochthonous human infection is associated with increased age, 39 Hispanic ethnicity, and living in rural 40 , 41 or poverty-stricken 39 areas or near the United States–Mexico border. 29 , 42 Wild and domestic animals, including military working dogs, may have an increased risk due to oral ingestion of triatomines. 29 …”

Assessing the Effectiveness of Chagas Disease Education for Healthcare Providers in the United States

“…(15,21,22) In several studies of triatomines collected in Texas, more than 60% were infected with T. cruzi and of those infected many had human blood in their gut. (22)(23)(24)(25)(26) Many of these studies suggest that locally acquired infections in the United States may occur more frequently than previously thought, however due to a lack of knowledge about Chagas disease in the United States it is often overlooked. (18,27) Regardless of where a person is infected, less than 1% of people in the United States will ever receive a clinical diagnosis of Chagas disease and even fewer will ever receive treatment.…”

“…As a result, the Texas Chagas Taskforce (TCTF) was developed and focused on using a One Health approach to information dissemination. (25,33) The TCTF recognized the need for a structured education program and therefore developed an online webinar on Chagas disease targeting healthcare providers, veterinarians and public health professionals. The purpose of this paper is to analyze the e cacy of an online education program for health professionals in raising awareness of Chagas disease and to determine key focus areas for improving knowledge on this complex disease.…”