React 1 Principal

REACT-1: Virus Prevalence in England

How is the pandemic progressing across England? This study will help to estimate COVID-19 virus infection prevalence by a REal-time Assessment of Community Transmission (REACT)

Keywords: SARS-CoV-2; COVID-19; prevalence; PCR; virus; point-of-care diagnostics

Q&A with the REACT team: REACT researchers Dr Atchison and Prof Barclay host a public Q&A session on antibody testing.

Short of a vaccine, testing is the only way out of lockdown.

Prof ara darzi

Description of the Study:

  • Title: REACT-1: a study of SARS-CoV-2 virus prevalence in the community in England.
  • Principal Investigators: Steven Riley, Christina Atchison, Deborah Ashby, Christl A. Donnelly, Wendy Barclay, Graham Cooke, Helen Ward, Ara Darzi, and Paul Elliott.
  • Center of Implementation: Imperial College London, Imperial College Healthcare NHS Trust and Ipsos MORI.
  • Study Population: 100,000 to 150,000 people aged 5 years and above from 315 local authorities across England.
  • Study Type: Epidemiological cross-sectional study.
  • Design: Repeated surveys involving collection of virological swabs and reverse transcriptase polymerase chain reaction (RT-PCR) tests from a series of age-sex stratified representative population sample.

Objectives of the Study:

Principal Objectives: Estimate the SARS-CoV-2 infection prevalence in the community in England.

Secondary Objectives:
(1) Quantifying geographical variation in swab-positivity rates across local authorities.
(2) Investigating the association between swab-positivity and sociodemographic characteristics including age, gender, ethnicity and socio-economic status (SES).
(3) Prevalence and nature of symptoms comparing infected and uninfected individuals.

More about this Study:

Conclusions: All the monthly reports for REACT-1 studies to date can be found on this page.

Added value: REACT-1 involves cross-sectional surveys of viral detection (virological swab for RT-PCR) tests in repeated samples of 100,000 to 150,000 randomly selected individuals across England. This examines how widely the virus has spread and how many people are currently infected. The age range is 5 years and above. Individuals are sampled from the England NHS patient list.

REACT: The REal-time Assesment of Community Transmission (REACT) programme is a series of epidemiological studies that are seeking to improve understanding of how the COVID-19 pandemic is progressing across England. To do this, the programme is carrying out two major pieces of work that are looking at the possibility of using home sampling and testing to track the infection. REACT-1 programme is monitoring coronavirus infection levels over time, while REACT-2 programme is assessing antibody finger-prick tests and using these to estimate how far the virus has spread.

Together REACT-1 and REACT-2 will improve our understanding of the transmission of the virus in the community to help guide policies on continued social distancing and other control measures.

Other studies of REACT:Clinical and laboratory evaluation of SARS-CoV-2 lateral flow immunoassays“, “Public involvement and pilot testing to assess the feasibility of in-home self-testing for SARS-CoV-2 antibodies“, “Acceptability and usability study of in-home self-testing for SARS-CoV-2 antibodies in a population-based sample“, “Usability and validity of LFIA self-testing in key workers, including the assessment of dry blood spots for SARS-CoV-2 antibody detection and saliva for SARS-CoV-2 viral detection” and “National seroprevalence study of SARS-CoV-2 antibodies using a lateral flow immunoassay self-administered test”.

Imperial College London

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