1. National Centre for Epidemiology, Institute of Health Carlos III, Madrid, Spain, Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), Institute of Health Carlos III, Madrid, Spain
2. Centre for the Coordination of Alerts and Health Emergencies, General Directorate of Public Health, Ministry of Health, Madrid, Spain
3. Vaccines Division, General Directorate of Public Health, Ministry of Health, Madrid, Spain
4. Spanish Agency of Medicines and Medical Devices-AEMPS, Madrid, Spain