Tuberculosis (TB) was once thought to be totally under control, an ancient, historical disease that has been handled easily with a course of antibiotics over a few to several months.
Now, TB is making a strong comeback mostly among the less well-off financially and the more immune challenged. This TB surge's bacteria has figured out most of the current antibiotics that once dominated them. It's simply termed "multi-drug resistant tuberculosis" or MDR-TB.
So far, this TB variation plagues the less fortunate in less developed nations or immune compromised individuals. But among those actually infected, there are around a third who don't manifest symptoms but are carriers. And this multi-drug resistant TB bug is getting around.