REACT-1: real-time assessment of community transmission of coronavirus (COVID-19) in September 2020
Updated 29 October 2020
Applies to England
© Crown copyright 2020
This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.
Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.
This publication is available at https://www.gov.uk/government/publications/react-1-study-of-coronavirus-transmission-october-2020-results/react-1-real-time-assessment-of-community-transmission-of-coronavirus-covid-19-in-october-2020
Methodology
A representative cross-section of volunteers tested themselves with swabs between 18 September and 5 October 2020.
Swabs were analysed using polymerase chain reaction (PCR).
Results
Over the 18 days of the completed round of testing, overall weighted prevalence of infection in the community was 0.60% (0.55%, 0.71%). Out of 174,949 swab results, 824 were positive. This is significantly higher than the prevalence of 0.13% (0.096%, 0.15%) measured during late August and early September 2020 and the highest observed prevalence of any round since this study started reporting in May.
Using only the data from the testing between 18 September and 5 October, the reproduction R in this round of testing is estimated to be 1.16 (1.05, 1.27) and the virus is calculated to be doubling every 29 days. The R rate is lower than that measuredfor the period 20 August and 8 September, when the R rate was 1.7 and the doubling rate 7.7 days.
Across the age bands, highest prevalence was among 18-24 year olds at 1.2% - 1 in 80 infected – and in addition had increased 8-fold for those aged over 65 compared to the period 20 August and 8 September.
The prevalence of infection increased in all regions between August 2020 and early October 2020. The highest unweighted prevalence of infection was in the North West at 1.02% (0.89%, 1.17%) followed by 0.91% (0.71%, 1.17%) in the North East and 0.63% (0.51%, 0.80%) in Yorkshire and The Humber.
Asian and Black ethnicity was associated with higher prevalence of infection at 0.90% (0.71%, 1.13%) and 0.73% (0.45%, 1.18%) respectively. People of Black and Asian ethnicity had up to 2-fold higher rate of infection compared with White participants. Prevalence has increased across all ethnic groups since August 2020.
Those living in large households of size 6 or 7+ had higher prevalence (0.81% [0.57%, 1.14%] and 1.06% [0.67%, 1.67%] respectively) than those in single occupancy households where prevalence was 0.35% (0.29%, 0.43%).
Conclusion
During the period 18 September to 5 October 2020, SARS-CoV-2 virus was circulating with significantly higher prevalence than between 20 August to 8 September and infections had increased substantially across the generations and country, with 60 in 10,000 infected.
Subsequent rounds of REACT-1 will allow further accurate assessment of trends in prevalence and transmission.
Background
Read the pre-print version of this report