1. Institute of Virology; Heinrich-Heine-University Düsseldorf; Düsseldorf Germany
2. Department of Pediatrics; Heinrich-Heine-University Düsseldorf; Düsseldorf Germany
3. Pediatric Infectious Diseases; Department of Pediatrics; Medical Faculty Mannheim, Heidelberg University; Theodor-Kutzer-Ufer 1-3 Mannheim Germany