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.

As part of our continuous review of reporting, over the comings months Public Health Scotland will be implementing some changes to present a consolidated weekly respiratory publication.

REVISION 12 January 2023: On 06 January 2023 Public Health Scotland announced that the Reproduction (R) number section within the COVID-19 Statistical Report would cease to be produced effective from 11 January 2023. The metadata file published on 11 January 2023 that accompanies this report has been revised to archive the R number tab.

Main points

Weekly respiratory main points

Due to the festive period, the laboratory confirmed diagnoses data included in this week’s report may not be complete, should be interpreted with caution and is subject to change.

Overall assessment:

• The proportion of NHS24 calls that were for respiratory symptoms decreased from High to Moderate activity level overall
• The incidence rate of influenza has decreased to High activity level overall.
• There were 1,215 influenza cases: 1,019 type A (not subtyped), 125 A(H3), 46 A(H1N1)pdm09 and 25 type B. This compares to 2,397 laboratory-confirmed cases reported during week 52.
• Influenza by age: all individual age groups decreased but remained above Baseline activity level, with 75+ age group at Extraordinary activity level.
• Influenza by NHS Board: three NHS Boards were at Moderate, eight was at High and three were at Extraordinary activity level.
• Mycoplasma pneumoniae and parainfluenza remained at Baseline activity level. Rhinovirus decreased from Low to Baseline activity level.
• Adenovirus remained at Low activity level. Seasonal coronavirus (non-SARS-CoV-2), and HMPV decreased from Moderate to Low activity level.
• RSV decreased from Moderate to Low activity level. The number of laboratory-confirmed RSV cases was 220. This compares with 296 laboratory-confirmed cases in week 52.
• The numbers of hospitalised patients who tested positive for influenza reported in weeks 51 and 52 are higher than those reported for any week since the start of the 2016/2017 season. The hospitalisation rate for influenza has been generally increasing since week 25 and was 23.1 per 100,000 in week 52. The highest hospital admission rate for confirmed influenza was among patients aged less than one year old (113.1 per 100,000).
• The hospitalisation rate for RSV was 3.2 per 100,000 in week 52, with the highest hospital admission rate for confirmed RSV noted in patients aged less than one year old (84.3 per 100,000). The hospitalisation rate for RSV peaked in week 38 and 39 in 2021 (4.5 per 100,000).
• In the Community Acute Respiratory Infection (CARI) sentinel surveillance system carried out at general practices across Scotland, rhinovirus was the highest circulating pathogen in the community since the start of the season in week 40 until week 49, followed by RSV for many weeks, and influenza A since week 40.
• NB: There has been an ongoing delay in getting complete test results for all samples, caused by a technical issue at the lab on 06/12/2022. This has led to a backlog. Results for the most recent week are therefore not available and updated data for week 52 is being reported this week. Results should be interpreted with caution as further samples are still expected and any retrospective changes in swab positivity will be reported on next week.
• Influenza vaccine data show that at the end of week 1, an estimated total of 2,501,132 individuals have received their vaccine. This includes 1,920,297 eligible adults of whom 959,823 are aged 65 years and over. In addition, 89.9% of those receiving their COVID winter booster and eligible for flu vaccine have received both vaccines at the same appointment. More detailed data for the 2022/23 winter programme are available on the PHS flu and COVID winter vaccination dashboard.
• All-cause excess mortality for week 50 (the latest week not impacted by reporting delays) increased to Moderate activity level overall. There was an increase in the 65 and above age group to Moderate activity level but all other age groups remained at Baseline activity level. Although data for week 51 and later are still incomplete, all-cause mortality has increased to Low activity level in the 15-64 age group and to High activity level in the 65+ age group. Further examination of the cause of death in these individuals reveals an increase due to a range of non-infectious and infectious conditions, including COVID-19 and other respiratory pathogens.

COVID weekly main points

• In Scotland, in the week ending 28 December 2022, the estimated number of people testing positive for COVID-19 was 213,100 (95% credible interval: 172,000 to 258,300), equating to 4.05% of the population, or around 1 in 25 people (Source: Coronavirus (COVID-19) Infection Survey, UK - Office for National Statistics)
• In the week ending 08 January 2023, there were on average 1,297 patients in hospital with COVID-19, a 2.4% increase from the previous week ending 01 January 2023 (1,267)
• In the week ending 08 January 2023 there were 16 new admissions to Intensive Care Units (ICUs) with a laboratory confirmed test of COVID-19, an increase of 2 from the previous week (01 January 2023)
• By week ending 08 January 2023 of the 1,980,682 people vaccinated for COVID-19 as part of the Winter 2022 vaccination programme, 89.9% were vaccinated for Flu at the same vaccination appointment
• In the week ending 01 January 2023, there were 67 deaths involving COVID-19 (3 more than the previous week) (Source: National Records of Scotland)

Background

Weekly national respiratory report:

Surveillance of respiratory infection is a key public health activity as it is associated with significant morbidity and mortality during the winter months and particularly in those at risk of complications of influenza, e.g., the elderly, those with chronic health problems and pregnant women.

The spectrum of respiratory illnesses varies from asymptomatic illness to mild/moderate symptoms to severe complications including death. There is no single respiratory surveillance component that can describe the onset, severity and impact of influenza or the success of its control measures each season across a community.

This requires several complementary surveillance components which are either specific to respiratory infections or their control, or which are derived from data streams providing information of utility for other PHS specialities (corporate surveillance data). Together, the respiratory surveillance components provide a comprehensive and coherent picture on a timely basis throughout the winter respiratory season. influenza page on the HPS website (external website) for more details.

COVID-19 weekly statistical report:

Since the start of the outbreak, Public Health Scotland (PHS) has been monitoring a number of key indicators to assess the impact of the virus, including demands on the health system.

This report summarises the current COVID-19 data in Scotland, presenting statistics on estimated infection levels from the ONS COVID Infection Survey, wastewater infection levels, reported COVID-19 cases, COVID-19 hospital and ICU admissions and Flu and COVID-19 Winter 2022 Vaccination Programme uptake.

Further information

The next release of this publication will be 18 January 2023.