1. Department of Clinical Virology, School of Medicine, University of Crete, 71003 Heraklion, Greece
2. First Department of Paediatrics, ‘Aghia Sophia’ Children's Hospital, University of Athens School of Medicine, 115 27 Athens, Greece
3. Neonatal Unit, Division for Women's & Children Health, Noble's Hospital, IM4 4RJ Douglas, Isle of Man, British Isles
4. Second Laboratory of Microbiology, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
5. Department of Paediatric Radiology, ‘Mitera’ Children's Hospital, 151 23 Athens, Greece
6. Department of Paediatrics, ‘Penteli’ Children's Hospital, 152 36 Penteli, Greece
7. Paediatric Intensive Care Unit (PICU), ‘Penteli’ Children's Hospital, 152 36 Penteli, Greece
8. Paediatric Intensive Care Unit (PICU), ‘P. and A. Kyriakou’ Children's Hospital, 115 27 Athens, Greece
9. Department of Paediatric Cardiology, ‘Penteli’ Children's Hospital, 152 36 Penteli, Greece
10. Karolinska Institutet, Karolinska University Hospital, SE-117 77 Stockholm, Sweden