Trypanosoma cruzi infection diagnosed in dogs in nonendemic areas and results from a survey suggest a need for increased Chagas disease awareness in North America

Abstract

OBJECTIVE To describe the clinical presentation and outcome in dogs diagnosed with Trypanosoma cruzi infection in nonendemic areas and to survey veterinary cardiologists in North America for Chagas disease awareness. ANIMALS 12 client-owned dogs; 83 respondents from a veterinary cardiology listserv. PROCEDURES A retrospective, multicenter medical records review to identify dogs diagnosed with American trypanosomiasis between December 2010 and December 2020. An anonymous online survey was conducted August 9 to 22, 2022. RESULTS Diagnosis was made using indirect fluorescent antibody titer (n = 9), quantitative PCR assay (1), or postmortem histopathology (2). Time spent in Texas was < 1 year (n = 7) or 2 to 8 years (5). Time in nonendemic areas prior to diagnosis was < 1 year (n = 10) and > 3 years (2). Eleven had cardiac abnormalities. Of the 12 dogs, 5 had died unexpectedly (range, 1 to 108 days after diagnosis), 4 were still alive at last follow-up (range, 60 to 369 days after diagnosis), 2 were euthanized because of heart disease (1 and 98 days after diagnosis), and 1 was lost to follow-up. Survey results were obtained from 83 cardiologists in North America, of which the self-reported knowledge about Chagas disease was limited in 49% (41/83) and 69% (57/83) expressed interest in learning resources. CLINICAL RELEVANCE Results highlight the potential for encountering dogs with T cruzi infection in nonendemic areas and need for raising awareness about Chagas disease in North America.

The Unfortunate Abundance of Trypanosoma cruzi in Naturally Infected Dogs and Monkeys Provides Unique Opportunities to Advance Solutions for Chagas Disease

“…A similar level of infection was reported among shelter dogs in Louisiana [33]. Much like the situation with human Chagas disease, there is increasing recognition of the translocation of infected dogs, often from the southern to northern U.S., where the veterinary community may have minimal awareness of Chagas disease [34].…”

Positive clinical outcome using a modified dosing regimen of benznidazole in dogs at high risk for infection or acutely infected with Trypanosoma cruzi

“…5,17,18 Investigation into the role of benznidazole treatment for T cruzi infection in naturally infected dogs has been limited partly because of the lack of availability of the medication, knowledge of which animals will benefit from treatment, and lack of veterinary awareness of Chagas disease. 4,17 Consequently, the role of benznidazole treatment for T cruzi infection in dogs has not been well established, and treatment options remain limited.…”

“…Although the observed trypanocidal effects and limitation of cardiac damage, ECG, and echocardiographic abnormalities are encouraging, none of the studies has reported clinical outcomes related to progression of heart failure, mortality rates, survival time, or quality of life in affected dogs 5,17,18 . Investigation into the role of benznidazole treatment for T cruzi infection in naturally infected dogs has been limited partly because of the lack of availability of the medication, knowledge of which animals will benefit from treatment, and lack of veterinary awareness of Chagas disease 4,17 . Consequently, the role of benznidazole treatment for T cruzi infection in dogs has not been well established, and treatment options remain limited.…”

“…Chagas disease is a zoonotic parasitic infection caused by the protozoan hemoflagellate, Trypanosoma cruzi , and transmitted by triatomine insect vectors, commonly known as “kissing bugs.” Infection with T cruzi can cause cardiomyopathy, heart failure, and sudden death in dogs and is endemic in the southern United States and the temperate areas of southern South America 1‐4 . Benznidazole, a nitroimidazole prodrug with trypanocidal activity, is routinely used to treat T cruzi infection in humans.…”