1. Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, the Netherlands
2. Department of Immunology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, the Netherlands
3. Spaarne Gasthuis Academy, Hoofddorp
4. Pfizer Vaccine Clinical Research & Development, Pearl River, New York
5. Pfizer Vaccine Clinical Research & Development, Hurley, United Kingdom
6. Pfizer Vaccine Clinical Research & Development, Collegeville, Pennsylvania
7. Pfizer Vaccine Clinical Research & Development, Berlin, Germany
8. Julius Clinical, Zeist, the Netherlands
9. Department of Medical Microbiology, University Medical Center Utrecht, the Netherlands