Chagas Disease: When a “Kiss” Can Make You Sick

It’s called the “kissing bug,” but the insect known as triatomine is more foe than friend. These bugs have been making headlines because they carry a parasite that can cause an infection known as Chagas disease. Once confined to Central and South America, the infection is becoming more prevalent in the United States.

“Until recently, we assumed that every case came from travel to or immigration from those other countries,” explains Keith Armitage, MD, an infectious disease specialist at University Hospitals. “But now, we’ve documented cases that were acquired here, particularly in southern states.”

From Silent Bite to Serious Illness

Chagas disease is caused by a parasite called Trypanosoma cruzi (T. cruzi). It spreads through bites from so-called kissing bugs, typically during outdoor activities such as camping or hiking. The bite itself is painless, but if a person scratches or rubs the area – or touches their eyes or mouth – the T. cruzi parasite can enter the body.

“The bugs feed on blood, and then the microscopic feces left behind can contaminate the wound,” says Dr. Armitage. That mode of transmission explains why the insects earned their nickname: They tend to bite around the face, especially near the lips, while people are asleep.

One of the challenges of tracing cases of Chagas disease is that infection can remain silent for years. “Some people may notice redness or swelling at the site of the bite or feel mildly unwell, but many have no early symptoms at all,” explains Dr. Armitage. If more severe symptoms do appear, they typically include fever, headache, rash, diarrhea or vomiting.

The danger comes later, as the parasite lingers in the body. Over years or even decades, Chagas disease can cause serious complications – damaging the heart and leading to arrhythmias or heart failure, or affecting the digestive tract in ways that make swallowing or digestion difficult. “The importance of recognizing Chagas is that untreated infection can eventually cause significant organ dysfunction,” says Dr. Armitage.

Understanding Your Risk

For most Americans, the risk of infection remains very low. Still, people who spend significant time in rural or agricultural settings in the southern United States – or who travel to parts of Central or South America where the condition is more common – should take precautions. Wearing long sleeves and pants, using insect repellent and avoiding poorly constructed dwellings that may harbor the insects are all sensible steps. “It’s really the same kinds of steps you’d take to avoid mosquitoes or ticks,” Dr. Armitage adds.

If you have traveled or lived in an area where Chagas disease is more common and are worried about exposure, a simple blood test can confirm whether you’ve been infected. Two antiparasitic medications, benznidazole and nifurtimox, are available and are most effective when the infection is caught early. There is no vaccine available for Chagas disease at this time.

Changing Risks with Climate Shifts

Locally acquired infections have been reported in Texas, Arizona and New Mexico. It reflects a larger truth about infectious disease: As climates shift and insect populations change, so do the risks. “Just as we’ve seen Lyme disease surge in Ohio and nearby states over the last few years, Chagas is now showing up in parts of the U.S. where we never saw it before,” says Dr. Armitage. “Infectious diseases evolve with the environment, so it’s important to stay informed.”

For most Americans, Chagas disease offers more of a reminder than a threat – a reminder that global health challenges don’t always stay far away, and that staying educated is one of the best tools we have to protect ourselves.

Related Links

University Hospitals infectious disease specialists provide expert care for patients with vector-borne and parasitic illnesses, including those acquired through international travel.