1. Department of Neurosurgery, Chinese People's Liberation Army General Hospital‑Sixth Medical Center, Beijing 100037, P.R. China
2. Department of Neurology, Beijing Hospital, National Center of Gerontology, Beijing 100730, P.R. China
3. State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102200, P.R. China
4. Graduate School, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, P.R. China