ATLANTA -- A man with a rare and dangerous form of tuberculosis may have spread the disease to passengers and crew on two trans-Atlantic flights earlier this month, federal health officials said Tuesday.

Centers for Disease Control officials released information about the passenger and called for people on the same flights -- especially those who sat within two rows of him -- to get checked for the infection.

The infected patient traveled on two trans-Atlantic air flights and, in doing so, may have exposed passengers and crew to the extensively drug-resistant tuberculosis.

Which Flights?

The patient flew from Atlanta to Paris on May 12, arriving on May 13, on Air France flight 385. He returned to North America on May 24, on Czech Air flight 104, from Prague to Montreal. (Note: Earlier versions of this story incorrectly listed the Czech Air flight number.)

The man then drove into the U.S. He is hospitalized in respiratory isolation, according to the World Health Organization. It was reported that he was under federal quarantine, the first time a patient has been placed in that situation since 1963. The president must sign off on that step.

The patient was potentially infectious at the time of the flights to and from Europe, and so CDC officials recommended medical evaluation of cabin crew members on those flights, as well nearby passengers, according to the World Health Organization.

Dr. Julie Gerberding, director of the CDC, said the government was not mandating testing for others on the flight, though it was a strong recommendation.

She said the agency was trying to balance individual freedom with the responsibility to protect the public.

What Is TB?

Tuberculosis is a disease caused by germs that are spread from person to person through the air. The disease usually affects the lungs, and can lead to symptoms such as chest pain and coughing up blood. Globally, it kills nearly 2 million people each year.

Thanks to antibiotics and other measures, the TB rate in the U.S. has been falling for years. Last year, it hit an all-time low -- a total of 13,767 cases, or about 4.6 cases per 100,000 Americans.

But health officials worry about "multidrug-resistant" TB, which can withstand the mainline antibiotics isoniazid and rifampin. About 1.2 percent of U.S. TB cases fall into that category, according to CDC statistics.

A more rare, even-worse category of "extensively drug-resistant" TB -- or XDR-TB -- does not respond to at least three of six classes of second-line drugs. Last year, there were two U.S. cases of that infection.