1. Directorate of Promotion and Prevention Ministry of Health and Social Protection of Colombia Bogotá Colombia
2. Research Directorate, Profamilia Association Bogotá Colombia
3. Global Immunization Division Centers for Disease Control and Prevention Atlanta Georgia USA
4. Pan American Health Organization Washington District of Columbia USA
5. Pan American Health Organization Bogotá Colombia
6. National Center for Immunization and Respiratory Diseases Centers for Disease Control and Prevention Atlanta Georgia USA
7. Biostatistics and Medical Informatics University of Wisconsin Madison Wisconsin USA
8. Universidad Nacional de Colombia Bogotá Colombia