World TB Day, falling on March 24 each year, is designed to build public awareness that tuberculosis today remains an epidemic in much of the world, causing the deaths of nearly 1.5M people each year, mostly in developing countries. It commemorates the day in 1882 when Dr Robert Koch astounded the scientific community by announcing that he had discovered the cause of tuberculosis, the TB bacillus. At the time of Koch's announcement in Berlin, TB was raging through Europe and the Americas, causing the death of 1 out of every 7 people. Koch's discovery opened the way towards diagnosing and curing TB.