Researchers are now suggesting that Chagas disease, a potentially fatal parasitic illness often overlooked, has become endemic within the United States, according to a recent study.
This condition is frequently termed a silent killer because it can remain undetected for many years before leading to severe health issues. It is transmitted by insects called kissing bugs, known for biting near the mouth.
The infection progresses through two main stages. Initially, the acute phase may show no symptoms or mild ones like fever and headache. Years later, the chronic phase can cause serious damage to the heart and digestive system, affecting about one-third of patients with cardiac disorders.
Globally, over 7 million people are infected with Chagas, resulting in thousands of deaths annually, primarily in Central and South America. While many U.S. cases were previously linked to travel, new evidence points to local transmission.
In a paper published this month, experts identified eight states—California, Arizona, Texas, Tennessee, Louisiana, Missouri, Mississippi, and Arkansas—with confirmed human cases from local sources, supporting the argument for endemic status.
"Acknowledging the endemicity of Chagas disease in the United States is crucial for achieving global health goals," the authors write in the study.
Most states do not monitor Chagas cases, making the true infection count unknown, but indicators suggest it is more widespread than thought. For example, Texas reported 51 locally transmitted human cases from 2013 to 2023 and over 400 cases in dogs during that period, with infected dogs found in many other states.
Gabriel Hamer, an entomologist at Texas A&M, told the Los Angeles Times that the known cases of Chagas likely represent "just the tip of the iceberg" of the disease’s actual spread.
Kissing bug species that carry Chagas have been detected in 32 states, covering much of the southern U.S.
Key Information on Chagas
Early detection is vital, as antiparasitic drugs can cure Chagas if administered soon after infection. However, effectiveness decreases over time.
"If we screened for it and caught it early, most patients could be cured," Dr. Salvador Hernandez, a cardiologist, told NewsNation. "The problem is, we don’t, and people end up dying or requiring terrifically expensive care, including organ transplants and surgery."
Once chronic, Chagas cannot be cured with medication, but treatment can delay serious complications. In advanced cases, patients may need pacemakers or heart surgery.
Early symptoms, if present, are often mild and resemble common illnesses like the flu, including fatigue and body aches. A distinctive sign is Romaña's sign, eyelid swelling from eye entry. Chronic signs involve heart and digestive problems.
Dogs may show no symptoms initially but can develop issues like swollen lymph nodes or heart problems later. The study emphasizes that recognizing Chagas as endemic will enhance efforts to address this disease, which is not limited to tropical regions.
