Abstract
1 Department of Virology, National Institute for Health Development, Tallinn, Estonia
2 Department of Virology, Immunology and Vaccinology, Swedish Institute for Infectious Disease Control, Stockholm, Sweden
3 Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
4 Department for Infectious Disease, Ida-Viru Central Hospital, Kohtla-Järve, Estonia
5 MP Chumakov Institute of Poliomyelitis and Viral Encephalitis, Moscow, Russia
6 St Petersburg Pasteur Institute, St Petersburg, Russia