1. Infection Biology, Department of Biomedicine, University Hospital of Basel, 4031 Basel, Switzerland
2. Clinical Microbiology, University Hospital of Basel, 4031 Basel, Switzerland
3. Department of Medical Microbiology and Immunology, and Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
4. Division of Infectious Diseases, University of Alberta, Edmonton, Alberta T6G 2E1, Canada