How have hospital admissions for Covid-19 and flu changed in recent years?

The most recent winter was particularly tough for the NHS, as it dealt with continued high numbers of Covid-19 cases at the same time as much higher numbers of flu admissions. In this chart of the week, Sophie Julian takes a look at how hospital admissions for Covid-19 and flu have changed in recent years, and reveals how this past winter saw the number of hospital admissions for flu overtake those for Covid-19 for the first time during the pandemic.

Chart of the week

Published: 09/05/2023

There are thankfully much fewer hospital admissions for Covid-19 than during the first two major outbreaks of the pandemic. But with these admissions seemingly starting to decline, this past winter saw a much steeper rise in admissions for flu than had been the case over the past few years.

The number of hospital admissions for Covid-19 was colossal during the first two outbreaks of the pandemic and rose to over 70,000 in January 2021. Covid-19 admissions have generally remained high since the start of the coronavirus crisis, with significant peaks in admissions reflecting individual outbreaks. However, since the start of the vaccine roll-out in December 2020, large peaks in admissions have been avoided, replaced by ongoing admissions and smaller peaks.  

The pattern for flu admissions differs. They follow a seasonal pattern, demonstrated by noticeable peaks in admissions during winter and a small number of admissions during the remainder of the year.  

This past winter (2022/23) saw continued high numbers of Covid-19 admissions at the same time as a stark increase in flu admissions. In December, the number of hospital admissions for flu overtook Covid-19 for the first time since the start of the pandemic – with the peak in flu admissions reaching over 26,000 that month. This compares to recent flu seasons where admissions per month hovered around 10,000. 

With all Covid-19 restrictions removed this past winter, an outbreak of flu was arguably unsurprising. People were able to gather socially more freely than they had done in previous Covid-19 winters and, due to reduced transmission in previous years, there was also less natural immunity in the community.

Fortunately, flu vaccine uptake this winter was relatively similar to previous years, with 79% of all people aged over 65 having received the vaccine as of the end of January, which would have reduced some of the worst effects.

The combined number of Covid-19 and flu hospital admissions this past winter remained below the total number of Covid-19 hospital admissions seen 12 months earlier. However, the pressure on the NHS throughout winter was intense, as became all too clear by extremely long ambulance waits and delays in admitting patients to hospital. This was the first winter where the NHS had to tackle both Covid-19 and high number of flu admissions. It’s plausible this same pattern will present for winters to come.

Data notes

  • Hospital admissions per month includes those individuals who were admitted to hospital with a primary diagnosis of flu or covid. Meaning Covid-19 or flu was the main reason they were admitted to hospital.
  • Using diagnosis code U071-U072 for Covid-19 and J09-J11 for flu.
  • The number of admissions does not include those who contracted Covid-19 or flu whilst in hospital.
  • The number of admissions in February for both flu and Covid-19 is an undercount because admissions that started in February but did not end until March or later are not included in the dataset.

Acknowledgements

  • This work uses data provided by patients and collected by the NHS as part of their care and support. Read more on our website www.nuffieldtrust.org.uk/about/corporate-policies#informationsecurity-and-data
  • This report uses Hospital Episode Statistics (HES) data (year range 2017/18 to 2022/23). Copyright © 2020, re-used with permission. A data data-sharing agreement with NHS England (DARS-NIC-226261-M2T0Q) governed access to and use of HES data for this project.

 

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