Duke Global Health institute, Duke University, Durham, USA;
Global Health Research Center, Duke Kunshan University, Kunshan, China;
National Center for TB control and prevention, China CDC, No 155 Changbai Road, Changping District, Beijing 102206, People's Republic of China;
Bill & Melinda Gates Foundation, Seattle, Washington, USA;
Bill & Melinda Gates Foundation, Beijing office, Beijing, China;