1 Clinic of Infectious Diseases, Department of Health Sciences, Azienda Socio Sanitaria Territoriale (ASST) Santi Paolo e Carlo, University of Milan, Milan, Italy.
2 Department of Viroscience, Erasmus Medical Center, Rotterdam, Netherlands.
3 Department of Paediatrics, Jessenius Faculty of Medicine, Comenius University in Bratislava, University Hospital in Martin, Martin, Slovakia.
4 Department of Clinical Immunology and Allergology, Jessenius Faculty of Medicine, Comenius University in Bratislava, University Hospital in Martin, Martin, Slovakia.