[1] Ctr Dis Control & Prevent, Natl Immunizat Program, Atlanta, GA 30333 USA
[2] Royal Childrens Hosp, Parkville, Vic 3052, Australia
[3] St Josefs Hosp, Freiburg, Germany
[4] Univ Washington, Seattle, WA 98195 USA
[5] Kaiser Permanente Hlth Care Program, Oakland, CA USA
[6] Merck Res Labs, West Point, PA USA
[7] US FDA, Rockville, MD 20857 USA
[8] Natl Inst Publ Hlth & Environm, NL-3720 BA Bilthoven, Netherlands
[9] Harbor UCLA Med Ctr, Torrance, CA 90509 USA
[10] Ctr Dis Control & Prevent, Atlanta, GA USA
[11] Univ Basel, Childrens Hosp, Basel, Switzerland