A New, Super-Fast TB Test Is the First New Test in 60 Years

A new speedier test for tuberculosis has been endorsed by the World Health Organization. The test will shorten diagnosis time from months to a few hours. Currently TB spreads and kills faster than it can be diagnosed. Michael Spector wrote in his recent New Yorker piece about TB in India that the country has nearly 2 million new cases each year, and every day a thousand people die of the disease, the highest number in the world.

Part of the problem is that there are so many misdiagnoses with TB because existing tests are unreliable and expensive, which results in patients not being properly treated.

WHO's press release today describes why this faster test is so critical to saving lives:

"This is really a groundbreaking and revolutionary new test," said Dr. Karin Weyer of the WHO's Stop TB department. "The last new test we had for TB was ... in the 1940s, and smear microscopy more than 100 years ago, and this is really the first breakthrough we've seen in rapid diagnosis of TB."

But what is exactly is the test? Neither CNN's report today from London or the WHO mentions what this new test is, although it' is most likely to be the GeneXpert mentioned in The New Yorker piece. GeneXpert requires no blood tests and uses a patient's DNA from saliva to diagnose TB in under two hours with 98 percent accuracy.

The GenExpert test was developed by Cepheid with support from the Department of Defense and recent funding from the Bill and Melinda Gates Foundation (full disclosure, this series is made possible by the BMGF), the Foundation for INnovative New Diagnostics and the National Institutes of Health.