[\'Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, United Kingdom.\', \'Public Health England, London, United Kingdom.\', \'Royal College of General Practitioners, London, United Kingdom.\']
Influenza and Respiratory Virus Surveillance, Vaccine Uptake, and Effectiveness at a Time of Cocirculating COVID-19: Protocol for the English Primary Care Sentinel System for 2020-2021.