A patient being treated at a Dallas hospital is the first person diagnosed with Ebola in the United States, health officials announced Tuesday. The unidentified man left Liberia on September 19 and arrived in the United States on September 20, said Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention. At that time, the individual did not have symptoms. "But four or five days later," he began to exhibit them, Frieden said. The individual was hospitalized and isolated Sunday at Texas Health Presbyterian Hospital.