REVIEW ARTICLE Harmonizing influenza primary-care surveillance in the United Kingdom: piloting two methods to assess the timing and intensity of the seasonal epidemic across several general practice-based surveillance schemes

H. K. GREEN, A. CHARLETT, J. MORAN-GILAD, D. FLEMING, H. DURNALL, D. RH. THOMAS, S. COTTRELL, B. SMYTH, C. KEARNS, A. J. REYNOLDS, G. E. SMITH, A. J. ELLIOT, J. ELLIS, M. ZAMBON, J. M. WATSON, J. MCMENAMIN AND R. G. PEBODY* Respiratory Diseases Department, Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK Royal College of General Practitioners, Birmingham, UK Public Health Wales, Cardiff, UK Public Health Agency, Belfast, Northern Ireland, UK Health Protection Scotland, Glasgow, UK Public Health England, Real-time Syndromic Surveillance Team, Birmingham, UK Public Health England Respiratory Virus Unit, Virus Reference Department, Reference Microbiology Services, PHE Colindale, London, UK