1. UK Health Security Agency, Colindale, London, United Kingdom
2. Public Health Wales, Wales, Cardiff, United Kingdom
3. Paediatric Infectious Diseases and Immunology, Bristol Royal Hospital for Children, Bristol, United Kingdom
4. UK Health Security Agency South West Regional Laboratory, Bristol, United Kingdom
5. Paediatric Intensive Care Unit, Bristol Royal Hospital for Children, University Hospitals Bristol & Weston Foundation Trust, Bristol, United Kingdom
6. Department of Paediatric Cardiology, Bristol Royal Hospital for Children, University Hospitals Bristol & Weston Foundation Trust, Bristol, United Kingdom
7. Public Health Agency, Belfast, United Kingdom
8. Evelina London Children’s Hospital, Guys & St Thomas National Health Service Foundation Trust, London, United Kingdom
9. Public Health Scotland, Glasgow, United Kingdom