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Vida Human Health

Hope for humans
Our efforts on behalf of dogs hold promise for people with Chagas. Visit often to learn about our progress toward a treatment.
300,000+ people in the U.S. are infected, many of whom don’t know it
Triatomines are also known as kissing bugs, cone-nosed bugs, and blood suckers.


Chagas disease is prevalent in the United States, Mexico, Central and South America. Trypanosoma cruzi is the parasite that causes Chagas. T. cruzi is spread by triatomine bugs, also known as kissing bugs. Kissing bugs emerge at night and tend to feed on people’s faces as they sleep. Infected kissing bugs bite humans, ingest blood, and then defecate on the person, spreading the parasite via a break in the skin or a mucous membrane. Often, the sleeping person unknowingly scratches or rubs the feces into the bite wound, eyes, or mouth.

T. cruzi can also be transmitted through blood trans- fusions. The U.S. Food and Drug Administration has approved screening tests for T. cruzi, making the blood supply safer for everyone.

What Should I Look For?

Chagas has two phases: an acute phase and a chronic phase.

The acute phase lasts for a few weeks or months after infection. People often don’t realize that they have been infected, because they might not have symptoms—or mild symptoms such as fever, fatigue, body aches, headache, rash, loss of appetite, diarrhea, and vomiting—that can easily be mistaken for something else.

A physical examination can reveal an enlarged liver or spleen, swollen glands, and local swelling (a chagoma) where the parasite entered the body. The most recognizable mark of acute Chagas disease is called Romaña’s sign, which includes swelling of the eyelids on the side of the face near the bite wound or where bug feces were deposited. Even if symptoms develop during the acute phase, they usually fade away on their own, within a few weeks or months. The infection can be more severe in young children and people with weakened immune systems.

During the chronic phase, the infection may remain silent for decades or even for life. However, some people develop:

Cardiac complications, which can include an enlarged heart, heart failure, altered heart rate or rhythm, and cardiac arrest (sudden death)

Intestinal complications, which can include an enlarged esophagus or colon and can lead to difficulties with eating or with passing stool

What Should I Do?

Physicians traditionally use antiparasitic drugs to treat acute and congenital Chagas infections, chronic infections in children 18 years or younger, and reactivated latent infections in people with weak immune systems. Anti-parasitic treatment is most effective when used early in the course of infection.

Many physicians in the U.S. are unfamiliar with Chagas, or they believe it’s limited to immigrants from Latin America. However, kissing bugs and Chagas disease are commonly found in Texas and the southern United States. People traveling to Central and South America are at risk if they visit areas with endemic triatomine bugs. If you think you might have Chagas or been bitten by a kissing bug, visit your healthcare provider. Chagas can be diagnosed by blood tests.