1. From MEDTAP International, Bethesda, Maryland;
2. UCLA Center for Vaccine Research, Torrance, California;
3. Aviron, Mountain View, California;
4. EMMES Corporation, Potomac, Maryland;
5. Southern California Kaiser Permanente Health Care Program, Panorama City, California;
6. National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland; and
7. St Louis University Health Science Center, St Louis, Missouri.