Vaccine advocates

USA:

Bill Gates
Neil Halsey MD
Dr. Samuel Katz
Dr. Paul A. Offit

Immunization Action Coalition
Institute of Vaccine Safety
National Network for Immunization Information
Children's Vaccine Initiative
The Immunization Gateway 
The Global Alliance for Vaccines and Immunization (GAVI)
Every Child By Two
National Healthy Mothers Healthy Babies Coalition (HMHB)