1 Division of Hand, Reconstructive and Plastic Surgery, Kantonsspital St. Gallen, Rorschacherstrasse, St. Gallen 9000, Switzerland.
2 Institute of Pathology, Kantonsspital St. Gallen, Rorschacherstrasse, St. Gallen 9000, Switzerland.
3 Institute of Virology, Vetsuisse-Faculty, University of Zurich, Zurich, Switzerland.
4 Division of Infectious Diseases and Hospital Epidemiology, Cantonal Hospital St. Gallen, Rorschacherstrasse, 95, House 22, St. Gallen 9000, Switzerland.