PetMD Seal

Chagas Disease in Dogs

3 min read

American Trypanosomiasis Parasitic Infection in Dogs


Chagas disease is an illness caused by the protozoan parasite Trypanosoma cruzi, which may infect dogs in several ways, including through blood exposure to the feces of “kissing bugs,” the ingestion of infected kissing-bugs, kissing-bug feces or prey (e.g., rodents), or congenitally from a mother to her offspring.


Once the parasites enter the cells in a dog’s body (often the heart muscle), they multiply and eventually rupture the infected cells. This is why Chagas disease is commonly associated with heart disease in dogs.


Chagas disease is endemic in South and Central America, but it is also found in the United States, typically in in Texas, Louisiana, Oklahoma, South Carolina, and Virginia. But the disease’s range is expanding as our climate warms.


Symptoms and Types of Chagas Disease


Two forms of Chagas disease are observed in dogs: acute and chronic. Some dogs experience an extended asymptomatic period between the two forms, which can last for months to years.


Acute Symptoms      

  • Fever
  • Depression
  • Lethargy
  • Diarrhea
  • Loss of appetite
  • Swollen lymph nodes
  • Enlarged liver or spleen
  • Neurologic abnormalities (e.g., seizures)
  • Sudden death


These symptoms may not be noticed by owners because they often resolve without treatment.


Chronic Symptoms

  • Weakness
  • Exercise intolerance
  • Increased heart rate (tachycardia)
  • Abnormal heart rhythms
  • Fluid accumulation throughout the body
  • Coughing
  • Death         


Causes of Chagas Disease


Although Chagas disease can only be acquired through an infection with the T. cruzi parasite, there are a variety of ways a dog may come in contact with the organism. Illness may occur when a vectora kissing bug (Triatominae)—bites the dog on the skin or on a mucous membrane (such as the lips) and leaves infected feces in the wound. It can also occur when a dog eats an infected prey animal (e.g., rodent) or ingests the feces from a kissing bug. The parasite can also be passed from a mother to her offspring.



Related Articles

Flatworm Parasite (Heterobilharzia) in Dogs

Heterobilharzia americanum is a waterborne flatworm trematode parasite that typically infects raccoons and dogs. The parasite follows a cycle...

Racoon Disease in Dogs

Most commonly called “raccoon disease” because of its prevalence in the raccoon population, baylisascariasis comes from contact with raccoon...

Hookworms in Dogs

Hookworms can be fatal, especially in puppies. As such, pet owners need to be vigilant for signs of hookworms in their dogs. These blood-sucking...

Rickettsial Infection in Dogs

Ehrlichiosis in dogs is a rickettsia infection caused by the organisms Ehrlichia canis and Ehrlichia lewinii. These bacteria are spread by the...