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May 31, 2012 -- Chagas disease is being called the new "AIDS of the Americas."
The shocking comparison has put this neglected tropical disease in headlines around the world.
Who's at risk? Is Chagas really as bad as AIDS? Here's WebMD's Chagas disease FAQ.
Chagas disease is caused by a parasite called Trypanosoma cruzi. The parasites multiply within cells of the body. Infected cells burst, releasing parasites into the bloodstream.
Chagas disease was first recognized in the modern era by Brazilian doctor Carlos Chagas in 1909. But the disease has been around for 9,000 years. Chagas parasites have been found in the remains of mummies from the ancient Chinchorro culture of South America.
There are two phases of Chagas disease: the acute phase and the chronic phase.
The acute phase of Chagas disease lasts for several weeks or months after infection. It often goes unnoticed, as symptoms may be mild. Acute Chagas disease is only very rarely fatal. Most at risk are young children or people with weakened immune systems.
The chronic phase of Chagas disease is more serious. When the parasite is not eliminated, the infection may remain silent -- without symptoms -- for decades. Chronic-phase symptoms appear in about a third of patients. They can be devastating.
The most common complication of chronic Chagas disease is a heart condition called chronic Chagas cardiopathy. These complications include enlarged heart, heart failure, severely altered heart rhythm, and heart attack.
Some patients with chronic Chagas disease get intestinal complications. These may include enlarged esophagus (causing difficulty swallowing) or enlarged colon (causing difficulty passing stool).
There are several ways Chagas disease is spread.
The most common way is through the bite of a family of blood-sucking insects called triatomes. They're better known as kissing bugs, assassin bugs, cone-nosed bugs, and reduviid bugs.
While most cases of Chagas disease are in Central and South America, 11 different species of the bugs live in the Southern U.S. They may be found as far north as Pennsylvania in the East and Northern California in the West.
Inside houses, the most common places to find the bugs are near pet resting areas (a good reason not to sleep with your pets), in areas infested by rodents, and in or around beds (particularly under mattresses or bedside tables).
These bugs usually come out at night. They feed on the blood of humans and other mammals, birds, and reptiles. The bugs are attracted to the lips -- hence the nickname "kissing bug" -- although bites may occur on other parts of the body.
The bug bite itself doesn't spread Chagas parasites. But while feeding, bug droppings are left near the wound. When these droppings get into the wound or mucous membranes (as when a person touches the droppings and then rubs his or her eye), the parasites enter the body.