Official Statistics

Changes to reporting over the winter period 2023 (starting from the week 41 report)

Updated 25 April 2024

Applies to England

As we move into the winter reporting period, these statistics are now updated weekly since respiratory virus activity is typically higher during the winter season. This report has also been extended to enable more granular surveillance of influenza, COVID-19 and other respiratory viruses through the winter to better support clinical and public health decision-making. In summary, this report includes more detail on:

• hospital, intensive care unit (ICU) and high dependency unit (HDU) admission rates
• emergency department (ED) attendances
• public Google search trends for influenza and COVID-19 symptoms
• acute respiratory infection (ARI) incidents in care homes and educational settings by virus type
• influenza: virus characterisation and antiviral susceptibility
• flu and COVID-19 vaccine uptake

Summary of changes to the main report

Laboratory surveillance

Respiratory DataMart system (England)

Updated:

• Figure 5. DataMart weekly positivity (%) for respiratory viruses, England
  • weekly positivity data for influenza has been added
• Figure 4. Respiratory DataMart samples positive for influenza and weekly positivity (%) for influenza, England
  • this has been separated into 2 figures (one figure with the number of samples positive and one figure with the weekly positivity for current season and previous seasons)

Added:

• Respiratory DataMart weekly positivity (%) for influenza by age, England
• Respiratory DataMart weekly positivity (%) for SARS-CoV-2 with previous season, England
• Respiratory DataMart weekly positivity (%) for SARS-CoV-2 by age, England
• Respiratory DataMart weekly positivity (%) for respiratory syncytial virus (RSV) with previous seasons, England
• Respiratory DataMart weekly positivity (%) for RSV by age, England

Confirmed COVID-19 cases (England)

Kept:

• Figure 1. Confirmed COVID-19 episodes tested under Pillar 1, based on sample day with overall seven-day rolling average polymerase chain reaction (PCR) positivity for Pillar 1 (%)
• Figure 2. Seven-day rolling average PCR positivity (%) of confirmed COVID-19 cases tested under Pillar 1 by age group
• Figure 3. Seven-day rolling average PCR positivity of confirmed COVID-19 cases tested under Pillar 1 (%) by UK Health Security Agency (UKHSA) centres

Added:

• Weekly incidence per 100,000 population by ethnicity (Pillar 1), England

Microbiological surveillance 

SARS-CoV-2 variants

Kept:

• Figure 18. Prevalence of SARS-CoV-2 variants amongst available sequences episodes for England from [week number] up to [week number]

Added:

• Total distribution of SARS-CoV-2 variants detected in England in the last 12 weeks, up to week [week number] (week ending [week number])

Influenza virus characterisation

This section has been added.

Influenza antiviral susceptibility

This section has been added.

Community surveillance

Acute respiratory infection incidents

Kept:

• Figure 6. Number of ARI incidents by setting, England
• Figure 7. Number of ARI incidents in all settings by virus type, England

Added:

• Number of ARI incidents in care homes by virus type, England
• Number of ARI incidents in educational settings by virus type, England

FluSurvey

This section will be added. No data will be available until November 2023.

Google search queries

This section has been added.

Flu Detector

This section has been added.

Syndromic surveillance

Added:

• Daily ED attendances for acute respiratory infection, England (a) nationally, (b) by age group and (c) by UKHSA centre
• Daily ED attendances for influenza-like illness, England (a) nationally, (b) by age group and (c) by UKHSA centre
• Daily ED attendances for acute bronchiolitis, England (a) nationally, (b) by age group and (c) by UKHSA centre

Primary care surveillance

Royal College of General Practitioners (RCGP) Clinical Indicators (England)

Kept:

• Figure 8. RCGP influenza-like illness (ILI) consultation rates, all ages, England

RCGP sentinel swabbing scheme in England

Kept:

• Figure 9. Number of samples tested for SARS-Cov-2, influenza, and other respiratory viruses in England by week, GP sentinel swabbing
• Figure 10. Proportion of detections of SARS-CoV-2, influenza, and other respiratory viral strains amongst virologically positive respiratory surveillance samples in England by week, GP sentinel swabbing scheme
• Figure 11. Weekly positivity (%) for COVID-19, Influenza and RSV in England by week, GP sentinel swabbing

Secondary care surveillance

This section has been restructured in the winter version of the report.

Summer surveillance includes:

• Hospitalisations, Severe Acute Respiratory Infection (SARI) Watch
• ICU and HDU admissions, SARI Watch
• Extra Corporeal Membrane Oxygenation (ECMO), SARI Watch
• RSV admissions, SARI Watch

Winter surveillance includes:

• Influenza, SARI Watch
• COVID-19, SARI Watch
• ECMO, SARI Watch
• RSV admissions, SARI Watch

Influenza, SARI Watch

Kept:

• Figure 15. Weekly overall influenza ICU or HDU admission rates per 100,000 trust catchment population with moving epidemic method (MEM) thresholds, SARI Watch, England
• Figure 16. Weekly influenza ICU or HDU admissions by influenza type, SARI Watch, England

Added:

• Weekly overall influenza hospital admission rates per 100,000 trust catchment population with MEM thresholds, SARI Watch, England
• Weekly influenza hospital admissions by influenza type, SARI Watch, England
• Weekly hospital admission rate by UKHSA centre for new influenza reported through SARI Watch
• Weekly hospital admission rate by age group for new influenza reported through SARI Watch
• Weekly ICU or HDU admission rate by UKHSA centre for new influenza, reported through SARI Watch
• Weekly ICU or HDU admission rate by age group for new influenza, reported through SARI Watch

COVID-19, SARI Watch

Kept:

• Figure 13. Weekly hospital admission rate by age group for new COVID-19 positive cases reported through SARI Watch
• Figure 14. Weekly overall COVID-19 ICU or HDU admission rates per 100,000 trust catchment population, SARI Watch, England

Updated:

• Figure 12. Weekly overall COVID-19 hospital admission rates per 100,000 trust catchment population, SARI Watch, England
  • information on COVID-19 as the primary reason for admission (yes or no) among SARS-CoV-2 positive patients by week of admission has been added underneath the figure

Added:

• Weekly hospital admission rate by UKHSA centre for new COVID-19 positive cases reported through SARI Watch
• Weekly ICU or HDU admission rate by UKHSA centre for new COVID-19 positive cases, reported through SARI Watch
• Weekly ICU or HDU admission rate by age group for new COVID-19 positive cases, reported through SARI Watch

ECMO, SARI Watch

Added:

• Laboratory confirmed ECMO admissions in adults (COVID-19, influenza and non-COVID-19 confirmed) to Severe Respiratory Failure (SRF) centres in the UK

RSV admissions, SARI Watch

Kept:

• Figure 17. Weekly hospitalisation (including ICU or HDU) admission rates by age group for new RSV cases reported through SARI Watch, England

Added:

• Weekly overall hospital admission rates (including ICU or HDU) of RSV positive cases per 100,000 population reported through SARI Watch, England
  • this has been separated into 2 figures: one figure with the rates and one figure with the positive cases

Mortality surveillance

COVID-19 deaths

This section remains the same as the summer report.

Daily excess all-cause mortality (England)

This section remains the same as the summer report.

Influenza vaccination

Influenza vaccine uptake in GP patients

Added:

• Cumulative weekly influenza vaccine uptake by target group in England
• Cumulative weekly influenza vaccine uptake in those aged 2 and 3 years in England

COVID-19 vaccination

COVID-19 vaccine uptake in England

Kept:

• Figure 19. Cumulative weekly COVID-19 vaccine uptake in those who are living and resident in England vaccinated with a Spring 2023 booster since 3 April 2023

Added:

• Provisional cumulative people vaccinated with any dose of COVID-19 vaccine in the last 3 months, 3 to 6 months and vaccinated more than 6 months ago

 International update

Global COVID-19 update

In this section, only the links were kept.

Global influenza update

In this section, only the links were kept.

Influenza in North America

In this section, only the links were kept.

Influenza in Australia

In this section, only the links were kept.

Other respiratory viruses

In the avian influenza and other zoonotic influenza section, only the links were kept.

In the Middle East respiratory syndrome coronavirus (MERS-CoV) section, only the links were kept.

Summary of changes to additional surveillance graphs document

Respiratory DataMart system (England)

Kept:

• Respiratory DataMart – Influenza weekly positivity by UKHSA region
• Respiratory DataMart weekly positivity (%) for RSV by UKHSA region

Added:

• Respiratory DataMart – Influenza subtypes (weekly number of positive samples)
• Respiratory DataMart – Influenza subtypes (weekly proportion positive)
• Respiratory DataMart – other respiratory viruses (weekly number of positive samples)
• Respiratory DataMart – other respiratory viruses (weekly proportion positive)
• Respiratory DataMart – other respiratory viruses by age group (weekly proportion positive)

Removed:

• Respiratory DataMart weekly positivity (%) for influenza by age, England

Confirmed COVID-19 cases (England)

Kept:

• Seven-day rolling average PCR positivity (%) of confirmed COVID-19 cases tested by sex under Pillar 1
• Weekly COVID-19 episodes tested under Pillar 1, per 100,000 population by age group and region, weeks 25 to 34
• Weekly COVID-19 episodes tested under Pillar 1, per 100,000 population by ethnicity and region, weeks 25 to 34
• Weekly COVID-19 rate tested under Pillar 1, per 100,000 population by index of multiple deprivation (IMD) quintile (1 being the most deprived and 5 being the least deprived)

Removed:

• Weekly confirmed COVID-19 case rates by episode, per 100,000 population (Pillar 1), by UKHSA centres and sample week
• Weekly incidence per 100,000 population by ethnicity (Pillar 1), England

Second Generation Surveillance System (SGSS)

Added:

• SGSS reported Influenza A, Influenza B, RSV, Adenovirus, Parainfluenza, Rhinovirus, hMPV cases by UKHSA region
• SARS-CoV-2 Whole Genome Sequencing (WGS) coverage, England

Kept:

• SARS-CoV-2 coverage of sequencing with a valid result and genotyping over time

Acute respiratory infection incidents

Added:

• Number of acute respiratory infection outbreaks reported to UKHSA by type of educational setting, England

Google search queries

This section has been removed.

Flu Detector

This section has been removed.

Primary care surveillance

Added:

• ILI consultations in Wales, Scotland and Northern Ireland

Secondary care surveillance

Kept:

• Weekly COVID-19 hospitalisation rate per 100,000 trust catchment population by age group and region, weeks 25 to 34
• Rate of COVID-19 hospitalisation (to all levels of care including ICU and HDU) by ethnic group, per 100,000 ethnic group specific trust catchment population, England

Removed:

• Weekly admission rates for hospital and ICU or HDU laboratory confirmed COVID-19 cases reported through SARI Watch
• Weekly ICU or HDU admission rate by UKHSA centre for new influenza, reported through SARI Watch
• Weekly ICU or HDU admission rate by age group for new (a) COVID-19 positive cases and (b) influenza, reported through SARI Watch
• Laboratory confirmed ECMO admissions (COVID-19, influenza and non-COVID-19 confirmed) to Severe Respiratory Failure centres in the UK - * SARI Watch data is provisional
• Weekly hospital admission rate by UKHSA centre for new COVID-19 positive cases reported through SARI Watch
• Rate of COVID-19 admission to ICU/HDU by ethnicity, per 100,000 trust catchment population, by month, England

Co/secondary infections with COVID 19

This section has been added.

COVID 19 vaccine uptake in England

This section has been removed.