Introduction The use of rapid molecular testing for influenza diagnosis is becoming increasingly popular. Used at the point of care or in a clinical laboratory, these tests detect influenza A and B viruses, though many do not distinguish between influenza A subtypes. The UK Severe Influenza Surveillance System (USISS) collects surveillance data on laboratory‐confirmed influenza admissions to secondary care in England. This study set out to understand how rapid influenza molecular testing was being used and how it might influence the availability of subtyping data collected on influenza cases admitted to secondary care in England. Methods At the end of the 2017/2018 and 2018/2019 influenza seasons, a questionnaire was sent to all National Health Service Hospital Trusts in England to evaluate the use of rapid influenza testing. Surveillance data collected through USISS was analysed from 2011/2012 to 2020/2021. Results Of responding trusts, 42% (13/31) in 2017/2018 and 55% (9/17) in 2018/2019 used rapid influenza molecular tests, either alone or in combination with other testing. The majority of rapid tests used did not subtype the influenza A result, and limited follow‐up testing occurred. Surveillance data showed significant proportions of influenza A hospital and intensive care unit/high dependency unit admissions without subtyping information, increasing by approximately 35% between 2012/2013 and 2020/2021. Conclusions The use of rapid influenza molecular tests is a likely contributing factor to the large proportion of influenza A hospitalisations in England that were unsubtyped. Given their clear clinical advantages, further work must be done to reinforce these data for public health through integrated genomic surveillance.

Background The universal paediatric live attenuated influenza vaccine (LAIV) programme commenced in the United Kingdom (UK) in 2013/2014. Since 2014/2015, all pre‐school and primary school children in Scotland and Northern Ireland have been offered the vaccine. England and Wales incrementally introduced the programme with additional school age cohorts being vaccinated each season. The Republic of Ireland (ROI) had no universal paediatric programme before 2017. We evaluated the potential population impact of vaccinating primary school‐aged children across the five countries up to the 2016/2017 influenza season. Methods We compared rates of primary care influenza‐like illness (ILI) consultations, confirmed influenza intensive care unit (ICU) admissions, and all‐cause excess mortality using standardised methods. To further quantify the impact, a scoring system was developed where each weekly rate/z‐score was scored and summed across each influenza season according to the weekly respective threshold experienced in each country. Results Results highlight ILI consultation rates in the four seasons' post‐programme, breached baseline thresholds once or not at all in Scotland and Northern Ireland; in three out of the four seasons in England and Wales; and in all four seasons in ROI. No differences were observed in the seasons' post‐programme introduction between countries in rates of ICU and excess mortality, although reductions in influenza‐related mortality were seen. The scoring system also reflected similar results overall. Conclusions Findings of this study suggest that LAIV vaccination of primary school age children is associated with population‐level benefits, particularly in reducing infection incidence in primary care.