1. Division of Pediatric Endocrinology, Department of Pediatrics, Emory University School of Medicine, 2040 Ridgewood Drive, Atlanta, GA 30322
2. Howard Hughes Medical Institute, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093
3. Department of Pediatrics, University of Utrecht, Utrecht, The Netherlands
4. Laboratory for Virology, National Institutes of Public Health and Environmental Protection, Bilthoven, The Netherlands