Chagas Disease
A parasitic infection that can affect the heart and digestion
Quick Facts
- Type: Parasitic infection
- Cause: Trypanosoma cruzi parasite
- Main spread: Triatomine (kissing) bug bites
- Long-term risk: Heart and digestive damage
Overview
Chagas disease, also called American trypanosomiasis, is an infection caused by a parasite called Trypanosoma cruzi. It is most common in parts of Latin America, where it spreads mainly through contact with the feces of triatomine insects, often called kissing bugs. With migration and other routes of spread, cases also occur outside these regions.
The disease has an early (acute) phase that is often mild or unnoticed, followed by a long-term (chronic) phase that can last for life. Many people never develop serious problems, but in a portion of those infected, the parasite slowly damages the heart or digestive tract over years to decades. Early treatment can cure the infection or reduce later complications.
Symptoms
Symptoms differ by phase:
- Acute phase (first weeks to months): Often mild or absent. May include fever, fatigue, body aches, headache, rash, loss of appetite, and swelling at the site of infection. A classic but uncommon sign is swelling around one eye.
- Chronic phase (years later): Many people have no symptoms. In those who develop complications, the heart or digestive system is affected.
Heart involvement can cause an irregular or slow heartbeat, palpitations, shortness of breath, and heart failure. Digestive involvement can cause difficulty swallowing or severe constipation due to an enlarged esophagus or colon.
Causes
Chagas disease is caused by the Trypanosoma cruzi parasite. It spreads in several ways:
- Kissing bug bites: The insect deposits infected feces near the bite or eyes; scratching rubs the parasite into the body.
- From mother to baby during pregnancy.
- Blood transfusion or organ transplant from an infected donor (now screened in many countries).
- Contaminated food or drink in some outbreaks.
The disease is not spread by ordinary person-to-person contact such as touching or sharing food at the table.
Risk Factors
- Living in or coming from rural areas of Latin America where kissing bugs are common
- Living in poor-quality housing where the insects can hide
- Being born to a mother infected with the parasite
- Receiving blood or an organ from an infected donor in settings without screening
Diagnosis
In the acute phase, the parasite can sometimes be seen directly in a blood sample under the microscope. In the chronic phase, diagnosis relies on blood tests that detect antibodies to the parasite, usually with more than one test for confirmation.
If chronic infection is confirmed, doctors evaluate the heart with an electrocardiogram (ECG) and other tests, and assess the digestive tract if symptoms suggest involvement, to look for complications and guide care.
Treatment
Treatment has two goals: killing the parasite and managing complications.
- Antiparasitic medication: Specific drugs can kill the parasite and are most effective in the acute phase, in children, and in early chronic infection. They may also be used in some adults to slow progression.
- Heart care: Medications for heart failure or irregular rhythms, and devices such as pacemakers, may be needed for heart damage.
- Digestive care: Treatments for swallowing problems or severe constipation, sometimes including surgery.
Treatment decisions depend on the person's age, phase of infection, and whether complications are present.
Prevention
- Improve housing and use insecticides to control kissing bugs in affected areas
- Sleep under insecticide-treated bed nets in high-risk regions
- Screen blood and organ donations for the parasite
- Test and treat pregnant women and newborns where infection is common
- Practice food safety to prevent contaminated food outbreaks
When to See a Doctor
See a doctor for testing if you have lived in or come from an area where Chagas disease is common, or if your mother was infected, even if you feel well, since chronic infection is often silent. Early detection allows treatment before complications develop.
Seek prompt or emergency care for symptoms of heart problems such as fainting, severe palpitations, chest pain, or shortness of breath, or for an inability to swallow or severe, persistent constipation, as these may indicate organ damage that needs urgent evaluation.
Frequently Asked Questions
How does Chagas disease spread?
It spreads mainly through the feces of triatomine (kissing) bugs, which enter the body when scratched into a bite or the eyes. It can also pass from mother to baby during pregnancy, through infected blood or organ donation, and occasionally through contaminated food or drink. It does not spread through ordinary contact.
Can Chagas disease be cured?
Antiparasitic medication can cure the infection, especially when given in the acute phase, in children, or early in chronic infection. In later stages, treatment may slow progression and complications are managed, but established organ damage cannot be reversed.
What long-term problems can it cause?
In a portion of those infected, the parasite slowly damages the heart, causing irregular rhythms and heart failure, or the digestive tract, causing an enlarged esophagus or colon with swallowing difficulty and severe constipation. Many people, however, never develop complications.
Why should someone get tested if they feel fine?
Chronic Chagas infection is often silent for years before causing heart or digestive damage. Testing people from areas where the disease is common allows early treatment, which can prevent or reduce serious complications later.
Is Chagas disease contagious between people?
Not through everyday contact. It does not spread by touching, sharing food at the table, or being near someone. It passes through specific routes such as the insect's feces, pregnancy, or infected blood or organ donation.
References
- Centers for Disease Control and Prevention (CDC). Chagas Disease.
- World Health Organization (WHO). Chagas disease (American trypanosomiasis).
- MedlinePlus, U.S. National Library of Medicine. Chagas disease.
- Pan American Health Organization (PAHO).