Chagas disease: an overview and more

Chagas disease is an infectious disease caused by the Trypanosoma cruzi (T. cruzi) parasite. The insect that carries this parasite lives in Central, South America, and Mexico, where the vast majority of infections occur, although some cases have recently been detected in the southern United States.

It is estimated that around 8 million people in Latin America have Chagas disease and most people do not know that they are infected.

If left untreated, Chagas disease can persist for a lifetime and cause serious heart and digestive problems.

Symptoms of Chagas disease

Chagas disease has two phases: an acute phase and a chronic phase. In each of these phases, the infection can cause little or no symptoms , or life-threatening consequences.

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Acute phase

Acute Chagas disease usually begins 1 to 16 weeks after infection with the T. cruzi parasite. Acute Chagas disease is usually a fairly mild illness, often without symptoms.

This sometimes causes flu-like symptoms, such as:

  • Hot
  • Fatigue
  • Headache
  • Rash
  • Muscle pain
  • Swollen lymph nodes

You may also notice the following symptoms:

  • Swelling where the bug bit you
  • Swollen eyelid
  • Loss of appetite
  • Digestive problems such as nausea, vomiting, or diarrhea.

Acute symptoms can persist for weeks or months and usually go away on their own, but the infection does not go away without treatment.

This infection can become chronic and cause later life-threatening complications, so treatment is important during the acute phase.

Heart damage: Sometimes acute Chagas disease can affect your heart. People with cardiac (heart) damage have symptoms of acute myocarditis (inflammation of the heart muscle) and may also have acute pericarditis (inflammation of the tissue around the heart).

Symptoms and signs of heart disease can include:

Most often, the heart problems seen in acute Chagas disease go away completely after a few months. However, some people with acute Chagas heart disease develop chronic heart failure rapidly, and about 5% die of heart disease in the acute phase of the disease.

Chronic phase

After the acute phase of Chagas disease passes, most people who do not receive treatment enter the chronic or latent phase of the disease. This phase of Chagas disease is characterized by the total absence of symptoms or consequences of the disease.

If you have undefined Chagas disease, you look and feel completely normal and you have a normal heart exam, including an EKG and echocardiogram. However, a blood test will show that you have a chronic T. cruzi infection. Many people remain in this latent phase without any symptoms for the rest of their lives.

The chronic phase of Chagas disease affects 20 to 30% of people and can last for decades.

Signs and symptoms of severe or life-threatening chronic Chagas disease may include:

  • Arrhythmia
  • Heart failure
  • Enlargement of the heart
  • Enlargement of the colon, which can cause severe constipation and abdominal pain.
  • Enlargement of the esophagus, which can cause pain and difficulty swallowing.
  • Sudden death

If you are in the chronic phase of Chagas disease, your lifetime risk of developing one or more of these cardiac or gastrointestinal complications is approximately 30%.

Chagas heart disease usually begins at least five years after the acute illness and can last much longer.

Chagas heart disease is a very serious problem, often resulting in death or serious disability. In fact, along with coronary artery disease, Chagas disease is the most common cause of heart failure in Latin America .


Chagas disease is caused by the parasite Trypanosoma cruzi (T. cruzi) , which is found in the feces of infected triatomeaceous bugs in South America, Central America, and Mexico. Triatomic bed bugs are common in rural areas, especially in dwellings made of mud, mud, straw, or straw, and they feed on the blood of humans and animals. Chagas disease is not common among urban dwellers and is generally limited to rural areas of Latin America, although cases occur worldwide.

T. cruzi has also been found in the intestines of Reduviid bed bugs in the southern United States, and transmission has rarely occurred in the southern United States.

Most people contract the disease when they are bitten by a triatomic insect that has infected the parasite from an infected person or animal.

Triatom bugs are nocturnal and tend to bite people at night when they sleep, which is why they are also called "healing bugs." They defecate immediately after being bitten, leaving the parasite on the skin where it can enter the body through a bite or by rubbing the parasite in the eyes, mouth, cut or scratch.

Chagas disease can also be contracted in the following ways:

  • In utero (infected mothers can pass it on to babies)
  • Obtaining an infected organ by transplant
  • Blood transfusion from an infected person.
  • Eating contaminated, undercooked or raw food;
  • Exposure in the laboratory


If you suspect that you have Chagas disease, your healthcare provider will ask about your symptoms and possible exposure to T. cruzi , and perform a physical exam. They may also order a blood test to check for antibodies to the parasite, which can confirm or rule out that you have Chagas disease.

Chagas Disease Discussion Guide

Get our printable guide to your next doctor's appointment to help you ask the right questions.

If your blood test is positive, your healthcare provider may perform additional tests to see if you are in an active or chronic phase and if you have developed any complications. These additional tests may include an echocardiogram, electrocardiogram (ECG), chest X-ray, abdominal X-ray, or upper endoscopy.

Watch out

Treatment of Chagas disease includes killing the T. cruzi parasite and treating the signs and symptoms of any complications, such as heart failure or cardiac arrhythmias. Acute Chagas disease and early unspecified Chagas disease are sometimes treated with antiparasitic drug therapy.

Benznidazole and nifurtimox are two drugs that may be effective against T. cruzi.

Both drugs can cause significant toxicity and only benznidazole is approved for use by the Food and Drug Administration (FDA). However, none of these are available in US pharmacies, so American healthcare professionals who need to treat a patient for T. cruzi should obtain these drugs directly from the Centers for Disease Control and Prevention. of Diseases (CDC). When taken early enough, these drugs are almost 100% effective in treating Chagas disease.

There is little evidence that treating adults with chronic or indeterminate Chagas disease with antiparasitic therapy markedly improves outcome. However, health professionals prescribe these drugs to people under 50 who have chronic or vague Chagas disease because the drugs can delay complications, but not cure the disease.


Chagas disease prevention is rarely a problem for Americans unless they live or travel to rural areas of Latin America.

If you are in a high-risk area, the following strategies may be helpful:

  • Remember to store and eat food.
  • Keep your living space, especially your bedroom, clean (this also applies to living areas for pets).
  • Ask your home demolition specialist to treat you with insecticide
  • Make sure all the holes and cracks in your house are covered.

Get the word of drug information

If you have contracted Chagas disease, do not be alarmed. In most cases, hospitalization is not required. And if it is treated immediately, the disease can be cured. Even if you don't realize you have a disease and are in the chronic phase, treatment can still help and you have a more than 70% chance of not developing any complications. If you have a complication, your symptoms can be significantly reduced, your quality of life can be significantly improved, and your survival can be prolonged with treatment.

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