Learning About Chagas Disease

Chagas disease is a potentially life threatening disease that typically found in parts of Latin America.  It is also called American trypanosomiasis named after the parasite Trypanosoma cruzi, which it is caused by.  This parasite and disease is spread through a 6 legged vector, or insect dubbed the “kissing bug” which carries the parasite.  You might be asking yourself why the triatomine bug is nicknamed the “kissing bug”, and the reason is not as cute as the name might let on.  They are called “kissing bugs” because their favorite place to feed, or suck blood, is the face. 

Chagas disease is spread through the feces of these insects, which defecate next to the bite where they feed from and parasites are able to enter a human’s blood stream through this break in the skin.  The infected bugs get the disease from an already infected animal or person, and emerge at night, many times in homes and bite unsuspecting humans, effectively spreading the disease.  According to the CDC, up to 8 million people throughout Central and South America, including Mexico are affected by Chagas disease.  Unfortunately, most don’t even know that they are infected, making treatment and prevention more difficult.


What are the symptoms?

The symptoms of Chagas disease present in two phases.

·         Acute phase: Either no symptoms or very mild symptoms, not unique to Chagas.  These include fever, fatigue, body aches, headache, and rash, loss of appetite, diarrhea, muscle pain, difficulty breathing, and vomiting. The one distinct symptom is swelling in the face or eyelids, near where the “kissing bug” bite was.  This visible sign, however, is present in less than 50% of cases.

·         Chronic phase: After remaining silent for decades, some people develop cardiac and intestinal complications, which can include enlargement of the heart, heart failure, altered heart rhythm and cardiac arrest, or enlarged esophagus or colon.

During the acute phase of the first few weeks or months of infection, the parasites circulate and high numbers within the blood, causing the symptoms mentioned.  After that symptoms usually dissipate, but if the infection is not treated it will persist and the affected person will enter into the chronic phase of the disease. 

In the chronic phase, the tropanisome parasites hide in the heart and digestive muscle causing the heart and digestive issues mentioned.  According to the World Health Organization, up to 30% of those with chronic Chagas will develop heart issues, and 10% will have neurological or digestive problems. This infection can eventually destroy the heart muscle causing heart failure and death. 

How is it treated?

If treatment is given early on into the infection during the acute phase, the cure rate is about 100%.  The medications given to kill the parasite are Benznidazole and nifurtimox.  The longer the infection persists, however, without treatment, the less likely or effective treatment becomes.  Currently, there is no vaccine available for Chagas disease.

Who is at risk?

·         Living in impoverished rural areas of Central America, South America and Mexico

·         Living in a residence that contains triatomine bugs

·         Residence in mud, adobe or thatch buildings

·         Blood transfusion/organ transplant from a person affected by Chagas disease

For anyone traveling to Central or South America, contracting the disease is rare.  This is because travelers typically stay in well-constructed buildings where the bugs don’t congregate.