A new microneedle patch will make TB tests not only painless, but also more accurate. Currently, tests for tuberculosis are carried out by injecting a bit of a purified TB derivative just below the skin at a precise depth and angle, and an improper injection, along with other factors, can cause a false result. In contrast, the patch - consisting of tiny needles coated with the derivative - will be applied like putting on a band aid. The needles will be too short to reach the nerves that...