1. Department of Medicine, Dalhousie University, Halifax, Canada.
2. Department of Medical and Surgical Sciences for Adults and Children, Clinic of Infectious Diseases, University of Modena and Reggio Emilia, Modena, Italy.
3. Faculty of Medicine, Dalhousie University, Halifax, Canada.
4. Department of Community Health & Epidemiology, Dalhousie University, Halifax, Canada.
5. Department of Psychiatry, University of California San Diego, San Diego, California.