1. Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Australia;
2. Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Australia;
3. Department of Pathology, Royal Melbourne Hospital, Parkville, Australia;
4. Department of Radiology, Royal Melbourne Hospital, Parkville, Australia;
5. Department of Neurosurgery, Royal Melbourne Hospital, Parkville, Australia;
6. The Peter Doherty Institute for Infection and Immunity, University of Melbourne and the Royal Melbourne Hospital, Parkville, Australia