[1] Univ Helsinki, Haartman Inst, Dept Virol, FIN-00014 Helsinki, Finland
[2] Univ Helsinki, Dept Obstet & Gynecol, Helsinki, Finland
[3] Univ Helsinki, Haartman Inst, Dept Pathol, FIN-00014 Helsinki, Finland
[4] HUCH Diagnost, Dept Virol, Helsinki, Finland
[5] HUCH Diagnost, Dept Pathol, Helsinki, Finland