1. These authors contributed equally to the work and share the first authorship.
2. Department of Virology, Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland
3. Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
4. Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
5. Centre for Biological Threats and Special Pathogens, Robert Koch Institute (RKI), Berlin, Germany. Current affiliation: Centre for International Health Protection, RKI, Berlin, Germany
6. Diseases Programme Unit, European Centre for Disease Prevention and Control (ECDC), Solna, Sweden
7. Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
8. These authors contributed equally to the work and share the last authorship.
9. Helsinki University Hospital Diagnostic Center, HUSLAB, Helsinki, Finland