Its medical name is Chagas disease -- named for the doctor who discovered it a century ago. It's caused by the bite of the assassin, or kissing bug, which passes on its parasites to humans and animals. It is not contagious otherwise, but without early intervention it can be life threatening.
"It causes a horrific condition known as Chagasiscardiomyopathy which is severe heart disease. It can result in extreme disability and sudden death as well, said Dr. Peter Hotez, with the Baylor College of Medicine's School of Tropical Medicine.
It was once thought to be restricted to tropical regions of Central, South America, and Mexico. However, Chagas and the bug that causes it are migrating north. Theories include climate change and international trade to the southern U.S., which puts Texas and Houston on the threat map.
Because Chagas often shows no symptoms, one Katy resident was stunned with her diagnosis in 2007.
"I was just -- what does this mean to me about a disease because I feel fine," said Rosemary Vorpahl.
She learned she was infected after a donation to the Gulf Coast Regional Blood Bank. The group began testing for Chagas several years ago.
"We found Chagas was becoming more prevalent in the United States and could be transmitted by a blood transfusion," Dr. Beth Hartwell with Gulf Coast Regional Blood Center said.
The most common way people are diagnosed in Texas is through testing at blood banks. Many doctors are unfamiliar with what was thought to be the ailment of other countries.
Now, Baylor College of Medicine has its National School of Tropical Medicine working on a vaccine for Chagas and other serious diseases that have spread from the third world to home soil.
"I like to call them the most important diseases that you've never heard of," Hotez said.
The CDC says often the disease goes unnoticed because those infected are either symptom free or exhibit signs that are common with other medical problems.
Symptoms for Chagas can include:
- Body aches
- Loss of appetite
The most recognizable sign of Chagas is eyelid swelling on the side of the face near the bite wound, or where the bug's feces was accidentally rubbed into the eye.
Symptoms may fade away on their own, but the CDC warns that the infection will persist if untreated.