1. These authors contributed equally to this work
2. Public Health Microbiology Unit, Bavarian Health and Food Safety Authority, Oberschleißheim, Germany
3. Unit of Virology, Bavarian Health and Food Safety Authority, Oberschleißheim, Germany
4. Ludwig Maximilians-Universität, Munich, Germany
5. State Institute of Health, Bavarian Health and Food Safety Authority, Oberschleißheim, Germany