Prevalent among persons who have lived in Mexico, Central America, and South America, Chagas disease can cause chronic and potentially severe cardiac and gastrointestinal disease decades after infection. The disease is named for Carlos Chagas, a Brazilian scientist who discovered a new species of Trypanosoma in the intestines of triatomine insects (called barbeiro or barber because they often bite the face). In 1908, Chagas named the new species T. cruzi after his mentor, Oswaldo Cruz. The next year, he identified the parasite in the blood of an ill 2-year-old girl named Bérénice, in what became the first description of this new human disease.