U.S. patients with XDR TB were 64% more likely to die during treatment than patients with multidrug-resistant tuberculosis, according to a data collected from 1993 to 2002.
"It's basically a death sentence," said Dr. Marcos Espinale, executive secretary of the World Health Organization's Stop TB Partnership.
The heightened concern comes as U.S. tuberculosis cases fell to 14,093 in 2005 from 14,516 in 2004, the CDC said. The rate of infection, 4.8 cases per 100,000 people, was the lowest since reporting began in 1953.
However, the TB rate in foreign-born people in the United States was 8.7 times that of U.S. natives, the CDC said. Most of the foreign-born cases in 2005 involved people from Mexico, the Philippines, Vietnam, India and China.
Untreatable Tuberculosis called 'a death sentence'