1. Kid Risk, Inc.; P.O. Box 590129; Newton; MA; USA
2. National Center for Immunization and Respiratory Diseases, Division of Viral Diseases; Centers for Disease Control and Prevention; Atlanta; GA; USA
3. Center for Biologics Evaluation and Research, Food and Drug Administration; Rockville; MD; USA
4. Department of International Health; Johns Hopkins Bloomberg School of Public Health; Baltimore; MD; USA
5. National Institute for Health and Welfare (THL); Helsinki; Finland
6. National Institute of Biological Standards and Control, Health Protection Agency; South Mimms; Potters Bar; Hertfordshire; UK
7. Dartmouth-Hitchcock Medical Center; Lebanon; NH; USA
8. Biologics Consulting Group, Inc.; Bethesda; MD; USA
9. Polio Eradication Initiative; World Health Organization; Geneva; Switzerland
10. Global Immunization Division, Center for Global Health; Centers for Disease Control and Prevention; Atlanta; GA; USA