Worldwide the number of TB cases is going down. The bad news is that the number of drug-resistant cases is going up. The World Health Organization estimates that the number of reported TB cases that were multi, extremely- or totally-drug resistant doubled between 2009 and 2011.
Until recently, it was extremely difficult to even diagnose drug-resistant TB, particularly in developing countries where disease is most prevalent. Tests had to be sent to fancy labs and could take up to three months to process.
But hope arrived a few years ago, in the form of a new screening tool called Xpert. It was designed to identify TB bacteria and the most common form of drug-resistance in only two hours. But as a new technology, no one was quite sure how effective it was.
