Dataset Information

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

ABSTRACT:

Background

Chagas 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 findings

To 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/significance

Our 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.

SUBMITTER: Garcia MN

PROVIDER: S-EPMC5104435 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

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

Garcia Melissa N MN O'Day Sarah S Fisher-Hoch Susan S Gorchakov Rodion R Patino Ramiro R Feria Arroyo Teresa P TP Laing Susan T ST Lopez Job E JE Ingber Alexandra A Jones Kathryn M KM Murray Kristy O KO

PLoS neglected tropical diseases 20161110 11

<h4>Background</h4>Chagas 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 ...[more]

PMID: 27832063

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Project description:BackgroundChagas disease is increasingly recognized in the southern U.S., where triatomine vectors transmit Trypanosoma cruzi among wildlife and domestic dogs with occasional vector spillover to humans. As in humans, clinical outcome in dogs is variable, ranging from acute death to asymptomatic infections or chronic heart disease. In order to characterize cardiac manifestations of T. cruzi infections, we tracked a cohort of naturally-infected dogs and a matched cohort of uninfected dogs. We hypothesized that selected measures of cardiac disease (abnormal rate, abnormal rhythm, and elevated cardiac troponin I (cTnI; a biomarker of cardiac injury)) would occur more commonly in infected than uninfected dogs matched by age, breed, sex and location. In addition to the clearly positive and negative dogs, we specifically tracked dogs with discordant test results across three independent serological assays to gather clinical data that might elucidate the infection status of these animals and inform the utility of the different testing approaches.ResultsWe placed an ambulatory ECG monitor (Holter) on 48 government working dogs and analyzed 39 successful recordings that met length and quality criteria from 17 T. cruzi-infected, 18 uninfected dogs and 4 dogs with discordant results. Overall, 76.5% of positive, 100.0% of discordant, and 11.1% of negative dogs showed > 1 ECG abnormality (p < 0.0001), and positive and discordant dogs had a higher mean number of different types of ECG abnormalities than negative dogs (p < 0.001-0.014). The most common cardiac abnormalities included supraventricular and ventricular arrhythmias and atrioventricular block. Positive dogs had higher serum concentrations of cTnI than both negative dogs (p = 0.044) and discordant dogs (p = 0.06). Based on dog handler reports, nearly all (4/5; 80%) dogs with reported performance decline or fatigue were T. cruzi-infected dogs.ConclusionsFurther understanding cardiac manifestations in dogs naturally infected with T. cruzi is critical for prognostication, establishing a baseline for drug and vaccine studies, and better understanding of zoonotic risk.

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Dataset Information

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

Background

Methodology/principal findings

Conclusions/significance

Publications

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

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