The World Health Organization (WHO) announced today that it is endorsing a new technology to diagnose tuberculosis.  The test, done on sputum samples and taking less than 2 hours to perform, identifies the presence of tuberculosis genetic material (coined the nucleic acid amplification test, or NAAT).  By contrast, conventional methods for diagnosing tuberculosis, such as sputum cultures, take several weeks.  In addition to confirming a diagnosis, the new test is also able to identify drug resistance, a particularly critical benefit in parts of the world where commonly used drugs to treat tuberculosis may not be effective.

According to Dr. Mario Raviglione, the director of WHO’s signature program to the halt the spread of tuberculosis “This new test represents a major milestone for global TB diagnosis and care.  It represents new hope for millions of people who are at the highest risk of TB and drug resistant disease.”  In a related development, co-developer of the test FIND ( the Foundation for Innovative and New Diagnostics) announced that the manufacturer of the new test (Cepheid) will offer a deep price discount to 116 low and middle income countries where TB is highly endemic. 

One of the main reasons tuberculosis killed 1.7 million people last year and infects almost 10 million worldwide annually (see map below for high risk areas)  is the rapid spread of tuberculosis among contagious, but undiagnosed persons.  The new test will dramatically reduce the time required for diagnosis, allowing quicker isolation of infected individuals and more timely initiation of treatment.  It will also allow physicians to rapidly identify patients for whom medications are not working. 

A few obstacles to the universal use of the NAAT test remain.  The machine requires an uninterrupted electrical source, a companion computer, and must be calibrated at least annually.  Nonetheless, scientists are hopeful that the new technology will significantly reduce both the spread and the ineffective treatment of a pathogen that remains endemic and deadly in much of the world.