Chagas Disease

What causes Chagas disease?

When people become infected by the parasite Trypanosoma cruzi, they can get Chagas disease. The feces of insects called triatomine, or “kissing” bugs, pass the parasite to humans. These bugs feed on the blood of animals and humans at night. Then they defecate. Infection can occur if you unknowingly wipe the feces into your eyes, nose, mouth, or a sore. 

The insects are usually found in rural Latin America, in places of widespread poverty. Experts believe that as many as 8 million people in South and Central America and Mexico have the disease. People in North America can also become infected, in much smaller numbers. But the disease is spreading as people travel more widely.

In addition to contact with feces from infected bugs, you can also get Chagas disease from:

• Blood transfusion
• Organ transplant
• Birth (mother-to-baby)
• Exposure in the lab
• Uncooked food contaminated with feces from infected bugs

You can't get Chagas disease from another person the way you can get a cold or the flu from someone else. You have to be exposed to the bug feces yourself. But you could get the disease if you get blood or an organ from a family member or anyone else with the infection.

Who is at risk for Chagas disease?

You're most at risk for Chagas disease if you:

• Have visited or traveled in rural Latin America
• Have been exposed to the blood products or received organs from someone infected with Chagas disease

What are the symptoms of Chagas disease?

Symptoms of Chagas disease vary from minimal to severe and life-threatening. They might be hard to tell apart from other illnesses. In some people, symptoms may be mild at first and then disappear for years or even decades, possibly never returning. But in the chronic phase of the disease, the parasite causes disease by long-term effects on your heart or intestinal muscles. This is why later symptoms often involve the heart or the digestive tract.

Symptoms of Chagas disease in the acute phase (the first few weeks or months) are:

• Mild, flu-like symptoms, such as fever, fatigue, body aches, and headaches
• Rash
• Loss of appetite
• Diarrhea
• Vomiting
• Swelling or a sore near the eye or on the side of the face where the bite or infection occurred (visible in fewer than half of infected people)
• Enlarged glands

Symptoms of Chagas disease in the chronic (or long-term) phase may include:

• Heart failure
• Abnormal heart rhythm 
• Trouble eating
• Trouble passing stool

The symptoms of Chagas disease may look like other health problems. Always see your healthcare provider for a diagnosis.

How is Chagas disease diagnosed?

To diagnose the condition, your healthcare provider will consider:

• Your overall health and health history
• Your description of symptoms
• Your travel history. This is because Chagas is often, though not always, caught in Latin America.
• A physical exam
• Lab blood tests
• Heart function tests, such as an electrocardiogram or echocardiogram once Chagas is confirmed

How is Chagas disease treated?

Treatment will depend on your symptoms, age, and general health. It will also depend on how severe the condition is.

Early treatment for Chagas disease is the most successful. When the disease is diagnosed later on, treatment for the parasite itself may no longer work. But treatment may improve complications. Recommended treatment may include:

• Antiparasitic medicine, which you may need to take for up to 3 months
• Continued watching of your heart function and getting treatments for heart failure
• Treatment of complications, such as arrhythmia, enlarged esophagus, or enlarged intestines

If you have a weak immune system, such as from HIV or cancer, you may need other treatment. Chagas disease can be more severe in people with these conditions and may lead to earlier death.

What are possible complications of Chagas disease?

If you have Chagas disease, you have about a 30% chance of developing complications.

They include:

• Infected heart muscle (myocarditis)
• Brain infection (meningoencephalitis)
• Enlarged heart
• Enlarged esophagus
• Enlarged colon
• Death

Can Chagas disease be prevented?

If you are planning to visit rural areas in Latin America, choose clean, well-built lodgings. Ask about pest management where you are staying. Consider using bed nets, wearing long sleeves and pants, and using bug repellent day and night.

When should I call my healthcare provider?

Chagas disease is not an emergency. But its effect on the heart and intestines might lead to an emergency. Get medical care right away if you have signs of heart failure, such as:

• Shortness of breath
• Ongoing cough
• Tiredness
• Confusion
• Rapid heart rate

This is especially the case if you have recently been to rural Latin America.

Key points about Chagas disease

• Chagas disease is a disease caused by a parasite.
• You’re most at risk for Chagas disease if you have visited or traveled in rural Latin America or if you have been exposed to the blood products or received organs from someone infected with Chagas disease.
• The symptoms may be mild at first and then disappear for years or even decades.
• In the chronic phase of the disease, the parasite causes problems inside your heart muscle or intestine.
• If you have Chagas disease, you have about a 30% chance of developing complications.
• Treatment for Chagas disease includes taking an antiparasitic medicine for up to 2 months and supportive therapies.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your provider tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your provider if you have questions.