Barbara Burleigh, associate professor of immunology and infectious diseases, studies Chagas disease, a leading cause of infectious heart failure. The disease is a major health and economic burden in Latin America, where it’s endemic, with roughly 8 million people infected and another 100 million individuals at risk of infection, mostly in rural, resource-poor settings.
How does Chagas disease cause infectious heart failure, and does it affect many people in the U.S?
Chagas is one of a group of so-called “neglected tropical diseases”—diseases that mainly affect the poorest countries and that have typically been overlooked because of the world’s focus on the “big three” diseases with the highest mortality rates: HIV/AIDS, malaria, and tuberculosis. In people with Chagas disease, it takes decades after the initial infection for severe symptoms to appear—which is why the disease is sometimes referred to as “the silent killer.” Symptoms include heart failure as well as severe swelling of the esophagus and/or colon, which greatly interferes with digestion. Chagas appears in people chronically infected with Trypanosoma cruzi, typically transmitted via contact with the feces of a blood-sucking insect called the triatomine, or “kissing bug.” Although triatomine bugs are found in the U.S.—mostly in the southern half of the country—people here have rarely been infected through bug bites, because the bugs thrive mainly in cracks and holes in houses made of mud or adobe or thatch—the kind of housing you’ll find in poorer countries.