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Researchers from one Washington, D.C., center confirmed that there was a high prevalence of Chagas disease in a sample of Latin American immigrants hospitalized with cardiac conditions.

Of 97 adults who underwent a transthoracic echocardiogram for cardiac symptoms and immigrated from a Chagas disease-endemic country in Latin America, 16 tested positive for Trypanosoma cruzi infection, reported Ajay Kerai, MD, of MedStar Washington Hospital Center, and colleagues.

The seroprevalence of Chagas disease rose to 25% in the subgroup of patients with a left ventricular ejection fraction (LVEF) of 50% or lower. In those with right bundle branch block, the seroprevalence was as high as 31.6%, Kerai and colleagues noted in a research letter in .

However, 91.7% of the patients had never heard of Chagas disease, despite being from an endemic region, the investigators said. "This underscores the critical need for increased awareness initiatives and community outreach efforts in the U.S. educating patients, which can play a pivotal role in enhancing screening rates."

Caryn Bern, MD, MPH, of the University of California San Francisco, agreed that the report "reinforces the need to screen people with epidemiological risk factors for Chagas disease."

She pointed to the , which list people who were born or lived for a prolonged period in Mexico and Central and South America -- whether or not they exhibit visible signs or symptoms -- among groups that should be screened.

Chagas disease, also known as American trypanosomiasis, is caused by T. cruzi infection and is endemic in all continental Latin American countries. Left untreated, some chronic infections can progress to cardiac complications such as heart failure, ventricular arrhythmias, conduction disturbances, and stroke. The CDC estimates that 20% to 30% of people with chronic T. cruzi infection .

Infection usually occurs in early childhood. The parasite can be transmitted by the triatomine bug, by food, during pregnancy or birth, through blood products, and through organ transplantation. While some people may not get sick at all, others develop symptoms such as swelling eyelids, fever, rash, and diarrhea.

Chagas can be cured if treatment is given in the acute phase, or the first weeks or months of infection. There are two antiparasitic treatments approved by the FDA: benznidazole for children ages 2 to 12 years, and nifurtimox (Lampit) for children from birth up to their 18th birthday.

The World Health Organization estimates that , mostly in Latin America, are infected with T. cruzi. Estimates place Chagas disease as the most frequent indication for pacemaker implants in Brazil.

Meanwhile, with human migration, the American Heart Association said the chronic disease has affected more than 300,000 people in the U.S. as of 2018.

Bern told 乌鸦传媒 that the 16.5% seroprevalence of Chagas infection in this study was not surprising and in line with the literature. For example, reported a 13% point prevalence of Chagas disease in Latin American immigrants with dilated cardiomyopathy. Another group reported a prevalence of 19% in people with an .

The present cross-sectional study was conducted at MedStar Washington Hospital Center from July 2021 to November 2022. Included were all adults who had undergone a transthoracic echocardiogram there due to symptoms such as chest pain, arrhythmia, stroke, syncope, abnormal electrocardiogram, non-ST-segment elevation myocardial infarction, or heart failure (excluding patients with known significant coronary artery disease and pregnancy). The study population was further narrowed down to those who had immigrated from a Chagas disease-endemic country in Latin America.

Ultimately, 97 people met study criteria and agreed to participate (mean age 59.9 years, 34% women, 65% from El Salvador). Their blood samples were sent out for commercial T. cruzi serology testing; positive samples were later sent to the CDC for additional confirmatory testing.

Among those who tested positive for Chagas, 81.3% said they had come from rural endemic regions. All recognized the vector triatomine insect when shown a color picture of it.

"Based on these findings, and per published recommendations, we recommend diagnostic serologic T. cruzi infection testing in patients who lived in rural endemic regions or recognize the triatomine insect and have clinical suspicion for [Chagas disease]," Kerai and colleagues wrote.

Chief among the study's limitations, however, was its highly selected and small sample, which limits the generalizability of the results.

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