1. Department of Neurology, National Neuroscience Institute, Singapore
2. Department of General Medicine, Khoo Teck Puat Hospital, Singapore
3. Division of Neurology, Department of Medicine, National University Health System, Singapore
4. Division of Neurology, Department of Medicine, Ng Teng Fong General Hospital, Singapore
5. Department of Laboratory Medicine, National University Health System, Singapore
6. Department of Infectious Diseases, Tan Tock Seng Hospital and National Centre for Infectious Diseases, Singapore
7. Division of Infectious Diseases, Department of Medicine, National University Health System, Singapore