Chagas Disease Risk for Dogs in a Kennel Environment
Chagas disease is caused by infection with the protozoal parasite Trypanosoma cruzi. Dogs become infected when they ingest the feces or bodies of infected kissing bugs. They can also become infected by blood transfusions or via transmission from a dam to her puppies. The disease is found in South and Central America, Mexico, and in the southern United States – especially in dogs housed in multi-dog kennels. Wildlife such as raccoons and opossums can also be infected with T. cruzi and serve as a reservoir for the parasite near dog kennels and human housing. Symptoms of Chagas disease vary and can be acute or chronic and mild or severe, including sudden death. Damage to the heart muscle, resulting in progressive heart disease, is the most common sign of infection. There is no gold standard diagnostic test for T. cruzi infection in dogs, but several serologic and PCR tests are available. Unfortunately, there is no known treatment for Chagas disease. Therefore, preventive strategies aimed at reducing exposure to the kissing bug vector are key.
Chagas disease also affects people, causing similar clinical signs and with similarly limited treatment options. Since T. cruzi infection rates in dogs may signal areas where people are at higher risk for the disease, understanding infection rates in the kissing bug vector and dogs provides valuable information to keep people and dogs protected. With funding from AKC Canine Health Foundation (CHF) Grant 02448: Canine Chagas Disease: Characterizing Cardiac Abnormalities, Vector Infection and Control Strategies, and Parasite Strains in Kennel Environments, investigators from Texas A&M University College of Veterinary Medicine studied the prevalence of Chagas disease and heart abnormalities in infected dogs.
Recently published results from this study documented a surprisingly high incidence or risk of infection in dogs housed in 10 different kennels in Texas. 64 dogs (half Chagas positive and half Chagas negative) were tested three times over a one-year period. 29 of the 30 infected dogs remained positive on multiple serology and PCR tests over time. 10 of the 34 negative dogs became positive during this one-year monitoring period. Overall, this means that a dog housed in these kennels has a 30.7% chance of becoming infected with T. cruzi within a year, despite numerous methods employed to control kissing bug exposure.
A dog housed in these kennels has a 30.7% chance of becoming infected with T. cruzi within a year.
Until successful prevention and treatment strategies are designed for the T. cruzi parasite, we must focus on controlling the disease vector – kissing bugs. Managing vegetation to keep wildlife away from kennels, use of insecticides, screens, and netting, avoiding outdoor lighting that attracts bugs, and housing dogs indoors are recommended measures to prevent dog and human exposure to infected kissing bugs. CHF and its donors continue to support research into the effects of T. cruzi infection in dogs and the development of more accurate diagnostic tests.
Learn more about canine Chagas disease from these CHF resources:
American Trypanosomiasis (Chagas Disease) - Information for Dog Owners
Webinar - Canine Chagas Disease - Studies of Naturally Infected Dogs and Kissing Bug Vectors
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