Weekly national seasonal respiratory report
Week ending 14 August 2022 – week 32

About this release

This release is a weekly report on epidemiological information on seasonal respiratory infection activity in Scotland. Due to the COVID-19 pandemic, health care services are functioning differently now compared to previous flu seasons so the consultation rates are not directly comparable to historical data.

Main points

Overall assessment:

• The proportion of NHS24 calls for respiratory symptoms in week 32 was at Baseline activity level overall. The 1-4, 5-14, 15-44, 45-64, 65-74 and over 75 age groups remained at Baseline activity level. The under 1 age group remained at Low activity level. All NHS Boards were at Baseline activity level.
• There were 37 influenza cases: 32 type A (subtype unknown), three A(H3) and two A(H1N1)pdm09. This compares to 34 laboratory-confirmed cases reported during week 31. Influenza incidence remained at Baseline activity level. In the under 1 age group, influenza activity increased to Low activity level.
• In week 32, coronavirus (non-SARS-CoV-2), HMPV, parainfluenza, rhinovirus and Mycoplasma pneumoniae remained at Baseline activity level. RSV remained at Low activity level and adenovirus increased to Low activity level.
• RSV activity remained at Low activity level in week 32. The number of laboratory-confirmed RSV cases for week 32 was 95. This compares with 126 laboratory-confirmed cases in week 31. Although at Low activity level, RSV cases are greater than what would be expected at this time of the year. Over half of the NHS Boards were at Baseline, five were at Low and one was at Moderate (Orkney) activity level. The 65-74 age group remained at Baseline activity level. The under 1, 1-4 and 15-44 age groups remained at Low activity level. The 75+ age group decreased from Low to Baseline activity level. The 45-64 and 5-14 age groups increased from Baseline to Low activity level.
• The majority (73%) of RSV detections in week 32 were in those aged under 5 years and the majority (87%) of diagnoses across all age groups occurred in the hospital setting.
• Adenovirus was at Low activity level, with 41 laboratory-confirmed cases in Scotland during week 32 (0.8 cases per 100,000 population). This compares with 46 laboratory-confirmed cases (0.8 cases per 100,000 population) in week 31.
• The hospitalisation rate for influenza was 0.4 per 100,000 in week 32, with the highest hospital admission rate for confirmed influenza noted in patients aged under 1 years old (4.1 per 100,000). The highest hospitalisation rate for influenza this season was reported in week 11 (1.3 per 100,000).
• The hospitalisation rate for RSV was 1.3 per 100,000 in week 32, with the highest hospital admission rate for confirmed RSV noted in patients aged less than 1 (47.3 per 100,000). The hospitalisation rate for RSV had peaked in week 38 and 39 in 2021 (4.5 per 100,000).

Background

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

The spectrum of respiratory illnesses vary 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 a number of 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 flu season. Please see the influenza page on the HPS website (external website) for more details.

Further information

The next release of this publication will be 25 August 2022.