1. Department of Neurology, Victor Babes University of Medicine and Pharmacy, Piata Eftimie Murgu 2, Timisoara 300041, Romania
2. Centre for Evidence Based Medicine, Nuffield Department of Primary Care Health Sciences, University of Oxford, Radcliffe Observatory Quarter, Oxford OX2 6GG, UK
3. Trip Database Ltd, Glasllwch Lane, Newport NP20 3PS, UK
4. Department of Continuing Education, University of Oxford, Rewley House, 1 Wellington Square, Oxford OX1 2JA, UK
5. Li Ka Shing Institute of Virology, Edmonton Alberta T6G 2E1, Canada
6. Department of Medical Microbiology & Immunology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
7. Departments of Medicine, Microbiology, Immunology & Infectious Diseases, and Pathology & Laboratory Medicine, Synder Institute for Chronic Diseases and O’Brien Institute for Public Health, Cumming School of Medicine, University of Calgary and Alberta Health Services, Calgary T2N 2T9, Canada