Question to the Department of Health and Social Care:

To ask the Secretary of State for Health and Social Care, if she will publish the assumptions, diagnostic definitions, uncertainty ranges and validation methods underpinning influenza and respiratory-virus models used to inform NHS winter planning and resource allocation.

The UK Health Security Agency (UKHSA) produces information on excess winter deaths due to flu and COVID-19 and extreme cold, which can be found at the following link:

https://www.gov.uk/government/statistics/influenza-in-the-uk-annual-epidemiological-reports

A more specific cold weather report focussing on cold mortality for 2024/25 is also available at the following link:

https://www.gov.uk/government/news/ukhsa-publishes-first-cold-mortality-report

Until May 2026, the Office for Health Improvement and Disparities assessed excess mortality weekly and then monthly by cause of death. Details can be found at the following two links:

https://www.gov.uk/government/statistics/excess-mortality-in-england-and-english-regions

https://www.gov.uk/government/statistics/excess-mortality-in-england--2

The UKHSA currently publishes weekly official statistics in the National Influenza and COVID-19 Report, which summarises information from the surveillance systems that are used to monitor seasonal influenza, COVID-19, and other seasonal respiratory illnesses, and can be accessed at the link below:

https://www.gov.uk/government/statistics/national-flu-and-covid-19-surveillance-reports-2026-to-2027-season

The UKHSA has also published academic papers that give details of our approach to COVID-19 and flu modelling, and these can be found at the following link:

https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1014644