Before there was COVID-19, tuberculosis was the world’s leading killer and is still responsible for 1.5 million deaths every year. TB, once known as “consumption,” has been a major scourge around the globe for centuries, and is on the rise again. Indian journalist Vidya Krishnan spent two decades researching the history of TB, and in her new book, “Phantom Plague: How Tuberculosis Shaped History,” she chronicles an infectious disease that not only has been a major force in the evolution of medicine and public health, but also today underscores the problems of global inequity, as the world battles new pandemics like COVID-19. Host Marco Werman speaks to the author.