Chagas Disease in Pets

Chagas Disease is a serious illness that's caused by a zoonotic protozoan parasite known as Trypanosoma cruzi. This parasite eventually works its way into the body's circulation system, where it spreads to all the other organs, although the heart and brain are the organs on which it has the most adverse effects.

This disease is transmitted via “kissing bugs” or “assassin bugs.” Animals who live in South and Central America are particularly at risk of contracting the disease. In the U.S., cases are also commonly reported in Texas, Louisiana, New Mexico, South Carolina, Oklahoma, Virginia, California, Florida, Georgia, North Carolina, and Maryland. Chagas Disease also may infect humans.

Dogs who contract Chagas Disease may live with it for months or even years before any signs and symptoms may arise. Even when the disease is in its asymptomatic stage, it can still be doing damage to the animal. From the moment a dog contracts the parasite, the disease can cause heart degeneration and inflammation. As a result, Chagas Disease can cause heart failure in affected dogs.

In most cases, younger dogs contract the acute form of the disease, while older dogs are more likely to suffer from a chronic form of Chagas Disease. In its acute form, the usual symptoms may include depression, diarrhea, anemia, lethargy, seizures, difficulty walking, increased heart rate, enlarged spleen, swollen lymph nodes, and congestive heart failure. In cases of chronic Chagas Disease, a pet will normally show signs of weakness, fainting, and increased heart rate.

Cats are more likely to be carrier hosts for Chagas Disease than they are to suffer acute problems resulting from it. But despite this, the disease can cause some cats to suffer convulsions and/or paralysis of the hind limbs. In cases where many the host's cells rupture at the same time, a fever also can occur.

If you live in an area that is prone to kissing or assassin bugs, and you notice signs that your pet may have a form of Chagas Disease or that he is acting differently, schedule an appointment with your veterinarian immediately.

Your veterinarian may perform a thorough examination of your pet, and in most cases, also will order a complete blood profile, urinalysis, serology, and an electrolyte panel to search for markers of a parasitic infection. An X-ray and echocardiogram also can be used to look for signs of any pulmonary diseases.

Chagas Disease has no known cure, and because it can be transmitted easily to humans, dogs and cats who contract the parasite commonly are euthanized. However, some drugs have shown promise when administered in the acute stage of the disease. Benznidazole has been shown to help control the development and progression of the disease, but total suppression has yet to be accomplished.

More common is the treatment of the conditions caused by the disease, such as heart arrhythmias and other complications.

The most-effective way to protect your pet from contracting Chagas Disease is to minimize the chances of him being exposed to parasite-carrying bugs like the kissing and the assassin bug. This can be a challenge if you live in a high-population area for these types of bugs.

Pesticides may help control the population in your yard, but before applying it, make sure that the chemicals are safe for use around pets. Pay attention to cracks and crevices when applying the solution, as these bugs often will crawl deep inside where they will be protected from the pesticide.