Tuberculosis (TB) has surpassed HIV to become the leading infectious killer of adults globally, causing almost 2 million deaths annually. Although this airborne disease has been treatable since 1948, global rates of TB have dropped less than two percent per year; an estimated 10 million incident cases continue to occur annually, including one million in children. While transmission of active disease is an important driver of the epidemic, the seedbed that feeds the epidemic is the more than two billion people estimated to have TB infection, five to ten percent of whom will progress to active disease during their lifetime. While any successful strategy aimed at TB elimination needs to address this reservoir of TB infection worldwide, much re...