1. Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention,1 and
2. Immunobiology Unit, Institute of Child Health, University College London, London, England2;
3. Division of Bacterial Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland3;
4. Pasteur Mérieux Connaught, Clinical Sero-Immunology Laboratory, Val de Reuil, France4;
5. Pasteur Mérieux Connaught, Clinical Serology, Swiftwater, Pennsylvania5;
6. Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota6;
7. National University Hospital, Department of Immunology, Reykjavik, Iceland7;
8. National Public Health Institute, Helsinki, Finland8;
9. Statens Serum Institut, Division of Microbiology, Copenhagen, Denmark9;
10. Wyeth-Lederle Vaccines and Pediatrics, West Henrietta, New York10;
11. University of Rochester, School of Medicine, Rochester, New York11; and
12. Merck Research Laboratories, Developmental Human Vaccine Serology, West Point, Pennsylvania12
13. Rollins School of Public Health, Emory University,13 Atlanta, Georgia;