Chagas Disease: A Growing Problem in the U.S.

Aileen M. Marty, M.D.

Director, FIU Health Travel Medicine Program

Triatoma infestans, “kissing bug”, a vector for Chagas disease

Chagas is a devastating disease that can cause serious heart damage, even death. Once considered localized to Latin America, where it is endemic, the Centers for Disease Control now estimates 300,000 cases in the United States; however, experts think the numbers are probably much higher, and they warn of a potential public health threat to Americans.

Chagas disease is caused by the parasite Trypanosoma cruzi (T. cruzi) and spread by bloodsucking insects called “kissing bugs” because they like to feed on people’s faces during the night.

How do you get it? The bug bites, sucks your blood, then it poops, and the parasites, which are in the insect poop can enter your body through the bite itself, or when you scratch. People infected with Chagas can pass it on through contaminated blood transfusions (the U.S. blood supply began to be screened for the Chagas parasite in 2007), organ transplantation, and pregnant mothers can transmit the parasite to their child. You also can get Chagas from food or beverages contaminated with feces from infected bugs or from infected bugs that get caught up in the food processing.

Swelling of the right eye known as Romaña's sign

Symptoms Acute phase: immediately after infection, the parasites start to swim around in your blood and most people experience symptoms, which may last a few weeks or months. These include fever, fatigue, body aches, headache, rash, loss of appetite, diarrhea, vomiting, and swelling around the bite site. A well-known symptom is “Romaña's sign”, a noticeable swelling of the eyelid. Sometimes early infection causes severe inflammation of the heart muscle or the brain, and 2% to 8% of people infected die during this phase of the disease. The infection may remain dormant for years or the rest of a person’s life. But in reality, although most people feel fine, and many never again experience symptoms, the parasite is usually hiding in the cells of the body. About 20% - 30% of infected people develop a Chronic phase, which is a debilitating and sometimes life-threatening disease that may include an abnormal heart rhythm that can cause sudden death, an enlarged heart that doesn’t pump properly, and an enlarged esophagus or colon that can lead to difficulties with eating or passing stool. There is no vaccine for Chagas, and despite great efforts in recent years; drug treatment for T. cruzi infection remains unsatisfactory.

Why WE should be concerned

Chagas is an emerging health concern for the nation and in particular for the southern United States where kissing bugs are common, and recent studies have shown they are just as capable of transmitting Chagas as their counterparts in Latin America. Another new study of Texas blood donors found that 1 in every 6,500 donors tested positive for the Chagas parasite. And if that’s not enough to raise red flags, a just-released study suggests that Chagas also can be transmitted by another bloodsucking relative of the kissing bug: the bed bug. It’s worth noting, the study has only been conducted on mice, but considering the rash of bed bug outbreaks all over the country, to be on the safe side, don’t let the bed bugs bite!