1. Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences , Nagasaki , Japan
2. The Institute of Medical Science, The University of Tokyo , Tokyo , Japan
3. Disease Control and Prevention Center, National Center for Global Health and Medicine , Tokyo , Japan
4. Division of Infectious Diseases, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania , USA
5. Departments of Microbiology and Infectious Diseases, Fujita Health University School of Medicine , Toyoake , Japan
6. Drug Development and Regulatory Science Division, Shionogi & Co, Ltd , Osaka , Japan
7. Pharmaceutical Research Division, Shionogi & Co, Ltd , Toyonaka , Japan