Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice. If you suspect exposure or experience symptoms, consult a qualified healthcare provider promptly.

Chagas Disease (“Kissing Bug Disease”) Is Spreading Across the U.S.: What You Need to Know

Chagas disease, often called “kissing bug disease,” is becoming a growing public health concern in the United States. Once considered rare and mostly linked to Latin America, evidence now shows that the parasite Trypanosoma cruzi is being transmitted locally in parts of the U.S., with many cases going undiagnosed.

What Is Chagas Disease and How It Spreads

Chagas disease is caused by a parasite called Trypanosoma cruzi. The primary vector is the triatomine bug, also known as the kissing bug, which carries the parasite. Infection typically occurs when the bug bites and then defecates near the wound. If the feces enter the body through broken skin, eyes, or mouth, parasite transmission can occur. Other routes include blood transfusions, organ transplants, congenital transmission from mother to baby, and contaminated food.

Spread and States Affected

Research indicates that Chagas disease is now considered locally transmitted in parts of the U.S. Texas is a hotspot, with dozens of locally acquired human cases reported in the past decade.

The kissing bug has been found in more than 30 U.S. states, and confirmed human infections acquired within the country have been documented in several states including Texas, California, Arizona, Louisiana, Missouri, Mississippi, Arkansas, and Tennessee. Animal infections have also been detected in multiple regions, suggesting that the parasite is circulating more widely than once believed.

Symptoms and Stages

Chagas disease has two phases:

• Acute phase: This occurs shortly after infection. Symptoms are often mild or absent. When present, they can include fever, fatigue, headache, body aches, swelling (especially eyelid swelling), rash, loss of appetite, diarrhea, nausea, and vomiting. Many people do not notice anything during this stage.

• Chronic phase: After months or years, about 20–30% of infected individuals may develop complications if untreated. These include heart problems such as an enlarged heart, irregular heartbeats, and heart failure, as well as digestive issues such as an enlarged esophagus or colon, difficulty swallowing, and chronic constipation.

Why Many Cases Go Undetected

Awareness among the public and healthcare providers remains low. Many doctors are unfamiliar with Chagas disease, and it is rarely considered during routine care unless the patient has a history of travel or exposure. Because the acute symptoms can be mild or vague, many people only discover the disease once serious complications develop, when treatment is less effective at reversing damage.

Prevention and Risk Reduction

Since there is currently no vaccine, prevention focuses on avoiding exposure to kissing bugs and other transmission routes. Helpful measures include:

• Sealing cracks in walls, roofs, and screens to keep kissing bugs out.

• Using insecticide sprays around homes in areas where bugs are present.

• Sleeping under insecticide-treated bed nets if living or camping in high-risk areas.

• Wearing protective clothing at night.

• Avoiding consumption of potentially contaminated food.

• Ensuring blood and organ donations are screened for the parasite.

• Pregnant women with possible exposure should consider screening.

Treatment Options

Two main medications are available to treat Chagas disease: benznidazole and nifurtimox. These medicines are most effective when used during the acute or early chronic phase. Their ability to reverse damage decreases the longer the disease has been untreated. Treatment may also involve managing heart or digestive symptoms for those in the chronic phase.

What You Should Do

If you live in or travel to southern U.S. states or other areas where kissing bugs are present:

• Be alert to insect bites, especially on the face, eyelids, or near the mouth.

• Do not ignore symptoms like unexplained fatigue, swelling of eyelids, fever, or irregular heartbeats.

• Talk to your doctor about testing if you believe you may have been exposed.

• Report sightings of kissing bugs to local public health agencies to help with monitoring.

Why Awareness Matters

Recognizing Chagas disease as endemic in parts of the U.S. can improve surveillance, diagnosis, and treatment access. Raising awareness, screening at-risk populations, and improving housing conditions can prevent serious illness and save lives. With hundreds of thousands of people in the U.S. estimated to be living with the infection—many unaware—public health education is key.