1. Department of Paediatrics and Adolescent Medicine; Turku University Hospital and University of Turku; Turku Finland
2. Research Centre of Applied and Preventive Cardiovascular Medicine; University of Turku; Turku Finland
3. Department of Clinical Virology; Turku University Hospital and Department of Virology; Turku University; Turku Finland
4. Department of Virology; University of Helsinki; Helsinki Finland
5. Department of Biostatistics; University of Turku and Turku University Hospital; Turku Finland
6. Department of Emergency Medicine and Division of Rheumatology, Allergy and Immunology; Department of Medicine; Massachusetts General Hospital; Harvard Medical School; Boston Massachusetts
7. Department of Pediatrics; School of Medicine and Public Health; University of Wisconsin; Madison Wisconsin
8. Department of Medicine; School of Medicine and Public Health; University of Wisconsin; Madison Wisconsin