One of the major challenges for global control of tuberculosis is that the current diagnostic tests are very slow and can require significant laboratory infrastructure. The tests are particularly difficult to manage in developing countries and are more complicated for folks with HIV. It’s also difficult to test for drug sensitivity. The challenge is that early detection is essential to interrupt transmission.
However, a new rapid (2-3 hour) test may be on the horizon. Researchers published an article in the New England Journal of Medicine this month that demonstrates promising results. The new test (called MTB/RIF) correctly identified more than 98% of patients with “smear-positive tuberculosis” and 72% of patients with “smear-negative tuberculosis”. The test also have very few false positives. Importantly, the new MTB/RIF test correctly identified (97%) of patients that had rifampin-resistant or -sensitive TB. More work will need to be done before the test replaces the current slow and labor intensive tests, but these are encouraging results that could provide a valuable new tool in the global TB fight.