TUBERCULOSIS kills nearly 2 million people every year. The existing vaccine, known as BCG, does not work that well, and no new vaccines are imminent. Yet we may already have a much better one sitting on the shelf: vintage BCG.
BCG is a live, weakened strain of Mycobacterium tuberculosis, the bacterium that causes TB. It is still given in some developing countries, where meningitis caused by M. tuberculosis is a threat to children. But BCG has fallen out of favour for preventing the most common form of TB in the lungs. It often gives little protection, mainly because people’s…
