Viral respiratory diseases (including influenza and COVID-19) in Scotland surveillance report

About this release

This weekly release by Public Health Scotland presents epidemiological information on respiratory infection activity, including COVID-19, across Scotland. Due to the dynamic nature of all datasets included in this report, figures contained within each update may be subject to change in future releases. Any revised figures will then be reflected within the latest update.

REVISION 8 February 2024: The Secondary Care Surveillance, subsection Hospital admissions, Influenza emergency hospital admissions and RSV emergency hospital admissions have been revised. Figures 25 and 26 have been revised to incorporate previously missing data from the 2021-22 season. Also, the total number of influenza sequences in the Microbiological surveillance, subsection genetic characterisation of influenza has been amended to reflect the current season 2023-24. This has had no impact on the narrative of the report or any previously published data, this has now been corrected.

Main points

Overall assessment 22 January to 28 January (ISO week 4):

• Measures of respiratory symptoms in the community via calls to NHS24 and attendances at GP consultations (GP ILI) were at Baseline activity level during the reporting period.
• In the CARI community surveillance system, swab positivity for influenza A remained elevated and increased to 23.8%, as compared to 18.2% in week 3. Increases in swab positivity were observed for seasonal coronavirus (non-COVID-19) (up to 12.4% from 7.2%) and human metapneumovirus (up to 10% from 4.2%). All other pathogens remained low or stable.
• Virology data showed influenza remained at High activity level in week 4. Moderate or High activity level was observed among all age groups. RSV remained at Low activity level, along with human metapneumovirus and seasonal coronavirus (non-COVID-19), while Mycoplasma pneumoniae decreased to Moderate activity level.
• Emergency hospital admissions because of influenza continued to decrease from 352 to 325, as did RSV, from 66 to 60. COVID-19 admissions, however, increased for COVID-19 from 207 to 227. ICU/HDU admissions increased slightly for influenza but remained at less than 5 for RSV and COVID-19.
• All-cause excess mortality for week 1 (week ending 7 January 2024, the latest week not impacted by reporting delays) remained at Low activity level overall and across most age groups.
• In winter 2023/24, Scotland administered 1,647,887 influenza (Adult 18+), 537,820 influenza (Children 6 months to 17 years), and 1,388,973 COVID-19 vaccines since September 4, 2023. Among adults 65+, 79.9% received influenza, and 79.1% received COVID-19 vaccines by week 4. Uptake is lower for influenza and COVID-19 vaccines compared to winter 2022/23.

Background

Tracking infectious respiratory diseases, including COVID-19 and influenza, is essential, especially in the winter when the disease burden can be highest. In Scotland, respiratory infection and associated morbidity are monitored using enhanced surveillance. This approach combines data from microbiological sampling and laboratory test results from community and hospital settings with data from syndromic surveillance of NHS 24 calls, primary care consultations for respiratory symptoms, hospital (including intensive care) admissions and other settings.

The intelligence generated from surveillance of laboratory, syndromic and community settings provide a comprehensive picture of current respiratory illness in Scotland. The data presented in this report provide a comprehensive and timely epidemiological picture that is essential for understanding transmission of infection and supporting patient care and NHS service planning and policy.

Seasonality patterns / seasonal variations

Respiratory illnesses are associated with seasonal increase in the autumn and winter. Seasonality patterns for both influenza viruses and non-influenza respiratory pathogens have been established through many years of surveillance data. Most influenza and non-influenza pathogens circulate in the autumn and winter in Scotland, although some are known to circulate in the spring and summer. Notably, COVID-19 transmission has been occurring in waves throughout the year as observed from surveillance data since the start of the pandemic in 2020.

Further information

The next release will be on 8 February 2024.

Find out more

Previous Publications

Versions of the Weekly national respiratory report publication released before 30 November 2022 may be found on the Public Health Scotland website.

Versions of the COVID-19 weekly statistical report publication released before 30 November 2022 may be found on the Public Health Scotland website.

Open data

Open data from this publication is available from the following weblinks:

• Viral respiratory diseases Open Data platform
• Flu and COVID vaccination uptake Open Data platform

Further data

• The COVID-19 Vaccine Wastage datafile was updated on 14 September 2023 to include the most recent information.
• The COVID-19 in Adult Care Homes in Scotland datafile was updated on 27 July 2023 to include more recent information.
• 28 September 2022 COVID-19 statistical report publication contains information on COVID-19 infection and vaccination in pregnancy in Scotland.
• 2 March 2022 COVID-19 statistical report publication contains information on Highest Risk (shielding patients list)
• 7 November 2023 Community Acute Respiratory Infection (CARI) surveillance in primary care contains information on flu Vaccine effectiveness in community settings.
• 25 May 2023 Interim 2022/23 influenza vaccine effectiveness: six European studies, October 2022 to January 2023, contains information on flu Vaccine effectiveness in hospital settings.
• 13 January 2024 Estimated number of lives directly saved by COVID-19 vaccination programs in the WHO European Region, December 2020 to March 2023, contains information on lives saved due to COVID-19 vaccination
• The COVID-19 Vaccine Wastage datafile was updated on 18 April 2024 to include the most recent information.