Tracking contacts of woman with rare TB

BETHESDA, Maryland (WPVI) -- Health authorities in 3 states are working overtime, to find out who had contact with a woman sick with a dangerous form of tuberculosis.

It is a tedious process, going through travel records to determine who this woman may have had prolonged, direct contact with.

However, it is vital to make sure no one else contracts this rare T-B.

The strain is extremely resistant to multiple drugs.

Three to four cases are reported each year in the United States, on average.

Federal officials say the woman traveled from India to the U.S., flying into Chicago's O'Hare International Airport in April.

She traveled to Missouri and Tennessee before she became sick enough to be admitted to a Chicago hospital, where she was quickly put into isolation.

"If you get this XDR-TB, 70% of the time, it's fatal. And she got her infection the way most people do, which is starting TB treatment, which can take 6 months of a year, and not completing the drug therapy," says Dr. Richard Besser, ABC News chief medical editor.

She is now in isolation at the National Institutes of Health outside Washington.

T-B isn't as easily spread as the flu - it takes close, prolonged contact.

But it can be very dangerous for people with weakened immune systems.

Tuberculosis is caused by bacteria spread from person to person through the air. It usually affects the lungs and can lead to symptoms such as chest pain and coughing up blood.

TB has been declining in the United States. But globally, each year it sickens about 9 million people and is a cause of 1.5 million deaths.