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Scientists think they’ve figured out how to make a century-old tuberculosis vaccine far more protective: Simply give the shot a different way. In a study with monkeys, injecting the vaccine straight into the bloodstream dramatically improved its effectiveness over today's skin-deep shot, researchers reported Wednesday. (Neergaard, 1/1)

The tuberculosis vaccine, known as BCG for Bacille Calmette-Guérin after the French scientists who developed it, is made from a live, weakened form of the tuberculosis bacteria found in cattle. It has been in use since 1921, is made by many companies and costs as little as $1 a dose for use in developing countries. It is considered safe even for newborns. However, it is not very effective. It protects infants against some devastating forms of TB, but eventually wears off and does not protect adolescents or adults against lung infections, the form that kills most TB victims. (McNeil, 1/1)

“The question is can we ever do IV vaccination [with the TB vaccine] in humans? That’s a little bit tricky,” he added. Experts said there are questions about the safety of delivering the live — though weakened — bacteria in a TB vaccine into the bloodstream. There would also practical hurdles to delivering an IV vaccine in low-resource areas, where health providers often have difficulty reaching people to provide even simpler vaccinations, like the polio vaccine given through drops in the mouth. (Thielking, 1/1)

The vaccine for tuberculosis has been around since the 1920s but it doesn't work very well. A new study shows that the vaccine could be far more effective if given at higher doses, intravenously. (Huang, 1/2)