1. Department of Public Health, HSE East, Dr Steevens’ Hospital, Dublin, Ireland
2. Epidemiology and Molecular Biology Unit, Temple Street Children’s University Hospital, Dublin, Ireland
3. Health Protection Surveillance Centre, Dublin, Ireland
4. Department of Public Health, HSE South-East, Kilkenny, Ireland
5. Department of Public Health, HSE Midwest, Limerick, Ireland
6. National Immunisation Office, Dublin, Ireland