DF is Head of the Division of Infectious Diseases, National University Hospital, Singapore, and Chair of The National Infection Prevention & Control Committee, Ministry of Health, Singapore. He is also the Chair of the GOARN steering committee. DLH is professor of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine. Previously he was the World Health Organisation’s assistant director-general for Health Security and Environment, and representative of the director-general for polio eradication.