Tuberculosis (TB) is the second leading infectious disease killer. According to the World Health Organization, every year, more than 10 million people fall ill with TB, and 1.5 million people die from the disease. The thing is, though, that it could be worse. Not nearly everyone who is infected has TB disease. “Tuberculosis is a disease that targets a small number of infected people,” Igor Kramnik, of Boston University, told BioWorld.