Curable, but contagious. Preventable, but potentially fatal. 4,600 deaths every day. This is reality of tuberculosis. Last century’s breakthrough cure for this age-old killer has saved countless millions of lives. But our progress hasn’t kept pace with TB’s ability to spread and develop drug resistance. Each year more than 4 million cases of TB go undiagnosed, untreated or unreported. As long as millions of people live with the disease without treatment, and continue to transmit the infection to others, we will not end the TB epidemic. On this World TB Day, we look at how investing in the fight against TB has made a real difference in the lives of people around the globe, while acknowledging the work that lies ahead in order to rid the world of its most deadly infectious disease.