He has drug-resistant TB and willfully disobeyed advice not to travel:

Federal and international officials are tracking down passengers and crew members on two trans-Atlantic flights earlier this month who may have been exposed to a man infected with an exceptionally dangerous form of tuberculosis.

The male passenger flew to Paris from his home in Atlanta on May 12 on Air France 385 and arrived in Paris on May 13. He returned to the United States on May 24 after taking Czech Air 104 to Montreal from Prague. The man drove into the United States that day and entered a hospital in New York City on May 25.

The man is now in an Atlanta hospital under federally enforced isolation after he was flown there from New York City on Monday in a plane owned by the Centers for Disease Control and Prevention in Atlanta.