[1] Univ Turin, Sch Med, Dept Publ Hlth & Pediat Sci, I-10136 Turin, Italy
[2] Azienda Osped Univ Maggiore della Carita, Mol Virol Lab, Novara, Italy
[3] Univ Hosp City Sci & Hlth Turin, Regina Margherita Childrens Hosp, Lab Citoimmunodiagnost, Turin, Italy
[4] Regina Margherita Childrens Hosp, City Sci & Hlth Turin, Pediat Oncohematol Stem Cell Transplantat & Cellu, Turin, Italy