AHA Statement Warns of Chagas Disease Risk
Chagas disease is caused by a parasite, transmitted by a blood-sucking insect— Trypanosoma cruzi – and less frequently, from mother to fetus or by contaminated food or drink. About one-third of people infected with it develop chronic heart disease. It is found mostly in Central and South America, but there are now an estimated 300,000 infected persons in the United States
An American Heart Association Scientific Statement issued on Aug. 20 is a warning about Chagas disease, saying during the past 40 years the disease has spread to areas where it had not traditionally been seen, including the United States. The statement has been published in the AHA journal Circulation.
Chagas disease is caused by infection with a parasite called Trypanosoma cruzi (T cruzi), and it causes chronic heart disease in about one-third of those infected.
The statement summarizes the most up-to-date information on diagnosis, screening, and treatment of T cruzi infection. Infection occurs when feces from the infected blood-sucking insect triatomine enters the skin through the bite site or in the eye. Triatomine insects are found in Central and South America, where they infest adobe houses, and in the southern United States. The disease can also be passed through contaminated food or drink, from pregnant mothers to their babies, and through blood transfusions and organ transplants.
The health risks of Chagas disease are well known in Latin America, where most cases are found in countries that include Brazil, Argentina, Bolivia, Paraguay, Mexico, and El Salvador, but doctors outside Latin America are largely unaware of the infection and its connection to heart disease. Besides the United States, countries where infected individuals have been diagnosed include Spain, with at least 42,000 cases, and also Italy, France, Switzerland, the United Kingdom, Australia, and Japan.
"This statement aims to increase global awareness among physicians who manage patients with Chagas disease outside of traditionally endemic environments," said Dr. Maria Carmo Pereira Nunes, MD, Ph.D, co-chair of the committee that produced the statement. "This document will help healthcare providers and health systems outside of Latin America recognize, diagnose and treat Chagas disease and prevent further disease transmission." Pereira Nunes is a cardiologist at the Federal University of Minas Gerais in Belo Horizonte, Brazil.
While 60-70 percent of people infected with T cruzi never develop any symptoms, those who do can develop heart disease, including heart failure, stroke, ventricular arrhythmias (heart rhythm abnormalities), and cardiac arrest. If it is caught early, an infection can be cured with medications that have a 60 to 90 percent success rate, depending on when in the course of infection the patient is treated.
"Early detection of Chagas disease is critical, allowing prompt initiation of therapy when the evidence for cure is strong," said statement co-author Dr. Caryn Bern, MD, MPH, professor of epidemiology and biostatistics at the University of California in San Francisco.
The risk of infection is extremely low for most travelers and residents of endemic countries. To minimize risk, people should avoid sleeping in houses with un-plastered adobe walls and/or thatch roofs, and avoid unpasteurized sugar cane juice, açai fruit juice, and other juices when visiting affected countries.