Jeremy Hawker Consultant Epidemiologist, Field Service, National Infection Service, Public Health England; Honorary Professor, Universities of Liverpool, Warwick, and Staffordshire, UK. Norman Begg Independent Vaccine Consultant; formerly GlaxoSmithKline Vaccines, Wavre, Belgium. Ralf Reintjes Professor, Epidemiology and Public Health Surveillance, Hamburg, Germany; Adjunct Professor, Infectious Disease Epidemiology, Tampere, Finland. Karl Ekdahl Head, Public Health Capacity and Communication Unit, European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden. Obaghe Edeghere Consultant Epidemiologist, Field Service, National Infection Service, Public Health England, UK. Jim van Steenbergen Independent Consultant; formerly Coordinator Communicable Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands.