1. Department of Virology; Medical University of Vienna; Vienna Austria
2. Institute for Pathology; University Hospital of Cologne; Cologne Germany
3. Division of Clinical Virology; Department of Laboratory Medicine; Medical University of Vienna; Vienna Austria
4. Division of Gastroenterology and Hepatology; Department of Internal Medicine III; Medical University of Vienna; Vienna Austria
5. Institute of Pathology; Medical University of Vienna; Vienna Austria