Guidance

SIREN study

Providing vital research into coronavirus (COVID-19) immunity and vaccine effectiveness nationally.

From:
UK Health Security Agency
Published
20 June 2022
Last updated
264 JulyOctober 2022 — See all updates

The SARS-CoV2 immunity and reinfection evaluation (SIREN) study is a unique, large-scale partnership with NHS healthcare workers providing an agile response to an evolving pandemic. It is one of the national core studies established in response to COVID-19 and a National Institute for Health Research (NIHR) urgent priority study, providing vital research into immunity and vaccine effectiveness.

The SIREN study was established early in the pandemic with participants undergoing regular testing for up to 2 years. Analysis of these testing samples helps the UK to evaluate the immune response to COVID-19, build understanding of the protection offered by vaccines and provide insight into COVID-19 reinfections.

Healthcare workers are enrolled in the study via the hospital site they work at. A total of 135 sites have participated in the study involving almost 45,000 participants, making SIREN the largest study of its kind globally. The SIREN study is UK-wide, running in partnership with the Public Health Agency Northern Ireland, Public Health Scotland and Public Health Wales.

The SIREN study is registered with ISRCTN.

Locations

One-hundred-and-thirty-five sites across the UK contributed to the first year of the SIREN study, with 87 sites contributing to the second-year extension – see locations list here.

Findings

The SIREN study has provided valuable evidence on immunity following SARS-CoV-2 infection and COVID-19 vaccination and provided surveillance data on infection and emerging variants. This evidence has played a critical role in informing the national COVID-19 response.

In January 2021 the SIREN study published its first analysis of protection following SARS-CoV-2 infection. Crucially the analysis showed that reinfection was possible and could occur, but that there was an over 80% reduction in infection among people who had previously contracted COVID-19 compared to those who had not.

In spring 2021 when the Alpha variant was dominant in the UK the SIREN study published its first analysis on the effectiveness of COVID-19 vaccines, focusing primarily on the Pfizer vaccine. The analysis showed that short-term vaccine effectiveness against infection 21 days after the first dose was 70% in the study population of healthcare workers and rose to 85%, 7 days after the second dose was received.

In February 2022 a later publication by the SIREN study looked at protection against SARS-CoV-2 infection following both previous infection and vaccination. It found that in previously uninfected individuals, 2 doses of the Pfizer vaccine were associated with high short-term protection against SARS-CoV-2 infection but that this protection reduced considerably after 6 months. Among those with a previous infection vaccination appeared to boost their immunity, providing strong and longer lasting protection. This provided important insights for COVID-19 vaccination programmes.

The SIREN study has published several articles to share its findings.

Examples include:

Partners

The UK Health Security Agency (UKHSA) runs the SIREN study in partnership with NHS sites, the Public Health Agency Northern Ireland, Public Health Scotland and Public Health Wales.

The SIREN study works with a number of academic partners. The SIREN Consortium was established in August 2021 and was successfully awarded a £1.57 million research grant by UK Research and Innovation (UKRI).

SIREN Consortium members include:

  • Protective Immunity from T cells to COVID-19 in Health workers (PITCH):
    • University of Oxford
    • University of Liverpool
    • University of Sheffield
    • Newcastle University
    • University of Birmingham
  • The Francis Crick Institute
  • Humoral Immune Correlates for COVID-19 (HICC)
  • Imperial College London
  • University of Glasgow
  • British Society for Immunology
  • GenOMICC

Contributors

Staff across the 135 sites have helped with the running of the study – download a study contributors list here (ODS, 26.9 KB).

Funding

The SIREN study is funded by UKHSA, the Department of Health and Social Care and NIHR, with contributions from the Scottish, Welsh and Northern Irish governments and funding awarded through research grants.

Further information

The SIREN study: answering the big questions.

SIREN: One year on.

SIREN: Two years on.


Site list

Key

Active = Active SIREN testing
Closed = Active SIREN testing stopped

SIREN study site Year 1 Year 2
England    
St George’s University Hospitals NHS Foundation Trust Active Active
University Hospitals Of Leicester NHS Trust Active Active
University Hospitals Plymouth NHS Trust Active Active
Leeds Teaching Hospitals NHS Trust Active Active
Mid Essex Hospital Services NHS Trust Active Active
North Middlesex University Hospital NHS Trust Active Active
Liverpool University Hospitals NHS Foundation Trust Active Active
West Suffolk NHS Foundation Trust Active Active
Sheffield Teaching Hospitals NHS Foundation Trust Active Active
University Hospitals of Morecambe Bay NHS Foundation Trust Active Active
Southend University Hospital NHS Foundation Trust Active Active
University Hospitals Bristol and Weston NHS Foundation Trust Active Active
King’s College Hospital NHS Foundation Trust Active Active
The Dudley Group NHS Foundation Trust Active Active
Royal Devon and Exeter NHS Foundation Trust Active Active
North Cumbria Integrated Care NHS Foundation Trust Active Active
St Helens and Knowsley Teaching Hospitals NHS Trust Active Active
Lewisham and Greenwich NHS Trust Active Active
The Newcastle Upon Tyne Hospitals NHS Foundation Trust Active Active
The Princess Alexandra Hospital NHS Trust Active Active
Imperial College Healthcare NHS Trust Active Active
Blackpool Teaching Hospitals NHS Foundation Trust Active Active
East Suffolk and North Essex NHS Foundation Trust Active Active
Hampshire Hospitals NHS Foundation Trust Active Active
James Paget University Hospitals NHS Foundation Trust Active Active
Buckinghamshire Healthcare NHS Trust Active Active
Sheffield Children’s NHS Foundation Trust Active Active
Basildon and Thurrock University Hospitals NHS Foundation Trust Active Active
Frimley Health NHS Foundation Trust Active Active
Calderdale and Huddersfield NHS Foundation Trust Active Active
United Lincolnshire Hospitals NHS Trust Active Active
Isle Of Wight NHS Trust Active Active
Warrington and Halton Teaching Hospitals NHS Foundation Trust Active Active
Royal Free London NHS Foundation Trust Active Active
Whittington Health NHS Trust Active Active
The Clatterbridge Cancer Centre NHS Foundation Trust Active Active
University Hospitals Of North Midlands NHS Trust Active Active
Royal Papworth Hospital NHS Foundation Trust Active Active
Shrewsbury and Telford Hospital NHS Trust Active Active
Devon Partnership NHS Trust Active Active
The Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust Active Active
London North West University Healthcare NHS Trust Active Active
Croydon Health Services NHS Trust Active Active
Nottingham University Hospitals NHS Trust Active Active
Mid Cheshire Hospitals NHS Foundation Trust Active Active
Dartford and Gravesham NHS Trust Active Active
Lancashire Teaching Hospitals NHS Foundation Trust Active Active
Bedfordshire Hospitals NHS Foundation Trust Active Active
Shropshire Community Health NHS Trust Active Active
Royal National Orthopaedic Hospital NHS Trust Active Active
Stockport NHS Foundation Trust Active Active
Hounslow and Richmond Community Healthcare NHS Trust Active Active
Salisbury NHS Foundation Trust Active Active
Derbyshire Healthcare NHS Foundation Trust Active Active
Birmingham and Solihull Mental Health NHS Foundation Trust Active Active
Black Country Healthcare NHS Foundation Trust Active Active
Solent NHS Trust Active Active
Southern Health NHS Foundation Trust Active Active
George Eliot Hospital NHS Trust Active Active
Lincolnshire Partnership NHS Foundation Trust Active Active
The Hillingdon Hospitals NHS Foundation Trust Active Active
Central and North West London NHS Foundation Trust Active Active
Lancashire and South Cumbria NHS Foundation Trust Active Active
Doncaster and Bassetlaw Teaching Hospitals NHS Foundation Trust Active Active
Bolton NHS Foundation Trust Active Active
Southport and Ormskirk Hospital NHS Trust Active Active
Norfolk and Norwich University Hospitals NHS Foundation Trust Active Active
Mid Yorkshire Hospitals NHS Trust Active Active
Somerset NHS Foundation Trust Active Closed
University Hospitals Of Derby and Burton NHS Foundation Trust Active Closed
Sherwood Forest Hospitals NHS Foundation Trust Active Closed
Gloucestershire Hospitals NHS Foundation Trust Active Closed
Hull University Teaching Hospitals NHS Trust Active Closed
Yeovil District Hospital NHS Foundation Trust Active Closed
Sandwell and West Birmingham Hospitals NHS Trust Active Closed
Royal Cornwall Hospitals NHS Trust Active Closed
Moorfields Eye Hospital NHS Foundation Trust Active Closed
Torbay and South Devon NHS Foundation Trust Active Closed
Ashford and St Peter’s Hospitals NHS Foundation Trust Active Closed
York Teaching Hospital NHS Foundation Trust Active Closed
Northern Devon Healthcare NHS Trust Active Closed
Countess Of Chester Hospital NHS Foundation Trust Active Closed
Portsmouth Hospitals NHS Trust Active Closed
Walsall Healthcare NHS Trust Active Closed
Royal Surrey County Hospital NHS Foundation Trust Active Closed
University Hospital Southampton NHS Foundation Trust Active Closed
Manchester University NHS Foundation Trust Active Closed
North West Anglia NHS Foundation Trust Active Closed
Royal United Hospitals Bath NHS Foundation Trust Active Closed
Surrey and Sussex Healthcare NHS Trust Active Closed
Great Western Hospitals NHS Foundation Trust Active Closed
Epsom and St Helier University Hospitals NHS Trust Active Closed
University Hospitals Coventry and Warwickshire NHS Trust Active Closed
Western Sussex Hospitals NHS Foundation Trust Active Closed
The Royal Wolverhampton NHS Trust Active Closed
Chesterfield Royal Hospital NHS Foundation Trust Active Closed
Brighton and Sussex University Hospitals NHS Trust Active Closed
Wye Valley NHS Trust Active Closed
Wirral University Teaching Hospital NHS Foundation Trust Active Closed
East Sussex Healthcare NHS Trust Active Closed
Maidstone and Tunbridge Wells NHS Trust Active Closed
Queen Victoria Hospital NHS Foundation Trust Active Closed
Cornwall Partnership NHS Foundation Trust Active Closed
The Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust Active Closed
Poole Hospital NHS Foundation Trust Active Closed
Northern Lincolnshire and Goole NHS Foundation Trust Active Closed
Leicestershire Partnership NHS Trust Active Closed
Birmingham Community Healthcare NHS Foundation Trust Active Closed
Dorset County Hospital NHS Foundation Trust Active Closed
Alder Hey Children’s NHS Foundation Trust Active Closed
Royal Berkshire NHS Foundation Trust Active Closed
Dorset Healthcare University NHS Foundation Trust Active Closed
Derbyshire Community Health Services NHS Foundation Trust Active Closed
Northern Ireland    
Southern Health and Social Care Trust Active Active
South Eastern Health and Social Care Active Active
Belfast Health and Social Care Trust Active Active
Western Health and Social Care Trust Active Active
Northern Heath and Social Care Trust Active Active
Scotland    
NHS Lothian Active Active
NHS Greater Glasgow and Clyde Active Active
NHS Lanarkshire Active Active
NHS Grampian Active Active
NHS Highland Active Active
NHS Fife Active Active
NHS Forth Valley Active Active
Golden Jubilee National Hospital Active Active
NHS Western Isles Active Active
NHS Borders Active Active
Wales    
Aneurin Bevan University LHB Active Active
Swansea Bay University LHB Active Active
Cwm Taf Morgannwg University LHB Active Active
Hywel Dda University LHB Active Active
Velindre NHS Trust Active Closed
Betsi Cadwaladr University LHB Active Closed
Powys Teaching LHB Active Closed

Please note: SIREN participants at sites who are no longer actively testing remain important contributors to the study. They will continue to receive communications and key study updates from the SIREN team and may be offered opportunities for further involvement.

Published 20 June 2022
Last updated 264 JulyOctober 2022 + show all updates

  1. Added link to 'Burden of SARS-CoV-2 infection in healthcare workers during second wave in England and impact of vaccines'.

  2. Added site contributors list.

  3. Added Study site list and link to 'SIREN: Two years on'.

  4. First published.

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