Many of our furry four-legged friends love to bask in the
sun or wrestle with other dogs in the soft green grass. As owners, we know how
essential outdoor exercise is for our dogs, especially certain breeds. It would
be comforting to believe our pets are completely safe while enjoying the
outdoors, but this is rarely the case.
Chagas, a potentially fatal disease transmitted to animals
through insects, is a danger for both inside and outside dogs. The disease is
caused by the protozoan parasite Trypanosoma cruzi, which is
spread to dogs through insects in the Reduviidae family, also commonly known as
cone-nose or kissing bugs. Dr. Ashley Saunders, associate professor of
cardiology at the Texas A&M College of Veterinary Medicine & Biomedical
Sciences, explains how insects are effective at spreading the disease.
“The T. cruzi organism is transmitted to
the host from a bite from an infected bug or ingestion of an infected bug,”
Saunders said. She also added that dogs can contract the disease without coming
into contact with an insect. “Transplacental transmission has also been
reported as a method of transmission.” This means the disease can be spread
from a mother to her offspring.
Once the dog has been exposed to the T. cruzi organism,
the parasite spreads through the body by becoming intracellular and invading
the blood stream of the dog. The brain and heart of the dog are the organs that
are most vulnerable to the disease.
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| Photo: Gabriel L. Hamer |
Chagas symptoms can be categorized as acute or chronic,
while some dogs can even be asymptomatic of the disease. In this case the
protozoan parasite can have months or years to cause inflammation and damage to
the heart. If clinical signs develop the disease can become even more fatal,
causing sudden death or heart failure. Acute symptoms include diarrhea,
lethargy, seizures, swollen lymph nodes, and increased heart rate, while
chronic symptoms include weakness, fainting, increased heart rate, and fatigue.
Dogs that experience acute symptoms are typically younger than two years old.
Insect control is a major key in managing the disease since
no vaccine currently exists. To protect your resting pup at night, reduce
lighting to decrease the amount of bugs that may come into contact with your
pet. Kennels with protective screens can also be effective in preventing the
dangerous bite of a kissing bug. Wood piles and other brushy areas can serve as
a breeding ground for infected insects, so try to keep your pet’s backyard area
clean and free of potential dangers.
Saunders explains that Chagas is commonly found in Latin
America and in southern states in the United States, including Texas. She urges
owners to contact a veterinarian if they think their dog is experiencing
symptoms of Chagas. If a dog becomes infected with Chagas, it is important to
test the other dogs in the household or litter as well. Females who are
infected should not be used for breeding as they can transmit the disease to
the litter via the placenta.
Whether your dog prefers the outdoors or only embraces the
wilderness for potty breaks, your pet is at risk for Chagas. With no vaccine or
treatment available, awareness and prevention is critical in protecting your
pet from Chagas disease.
Learn more about Chagas and identificationpictures of kissing bugs.
Pet Talk is a service of the College of VeterinaryMedicine & Biomedical Sciences, Texas A&M University.