1. Department of Clinical Infectious Diseases, Hammersmith Hospital, Imperial College Healthcare National Health Service Trust , London , United Kingdom
2. Department of Radiology, Charing Cross Hospital, Imperial College Healthcare National Health Service Trust , London , United Kingdom
3. Department of Neurology, Chelsea and Westminster Hospital, Chelsea and Westminster Hospitals National Health Service Foundation Trust , London , United Kingdom
4. Department of Infectious Disease, Faculty of Medicine, Imperial College London, Hammersmith Hospital , London , United Kingdom