Woman working in laboratory

The Real-time Assessment of Community Transmission (REACT) programme is the largest, most significant piece of research looking at how the virus is spreading across the country. 

The study is being carried out by a world-class team of scientists, clinicians and researchers at Imperial College London, Imperial College Healthcare NHS Trust and Ipsos MORI, and was commissioned by the Department of Health and Social Care.

REACT study findings 

13 May - Community infection trends in April and early May

Findings in brief

REACT scientists tested over 127,000 people in England between 15th April and 3rd May. They found that since the study's previous report in March, infections had dropped by half to 0.1% of the population, or 1 in 1000 people. The study also successfully analysed the genetic code of a small number of the positive swab samples, finding that the majority were the Kent variant while two, both in London, were the Indian variant of concern. 

7 May - Tracing virus variants in the community from January to March 2021

Findings in brief

REACT scientists looked at coronavirus genetic profiles from swab samples collected between January and March 2021. The majority of infections were with the Kent (B.1.1.7) variant. People infected with this variant were no more likely to report having any of the 'classic four' COVID-19 symptoms, but they were more likely to still have detectable virus antibodies 6 weeks after infection. The study also detected infections with the South African (B.1.351) variant in January, from people who had not travelled internationally, but not February or March. This suggests that this variant was spreading in the community but then faded out over time.

23 April - Community infection trends between May and September 2020 (peer-reviewed publication)

Findings in brief

This peer-reviewed study, published in the journal Science, reports findings from more than half a million swab tests taken between May and September 2020 in England. The researchers found that infections declined between May and July 2020 but then increased gradually from mid-August, accelerating into early September 2020 at the start of the second wave. When compared to COVID-19 cases detected through routine surveillance, the study found a longer period of decline and that infections were clustered in younger age groups.

08 April - Community infection trends in March

Findings in brief

Throughout March, and shortly after the reopening of schools, our study swabbed more than 140,000 people to find out how many people currently have the virus in England, and identify those who have a greater risk of infection. The research found that the rate of new infections levelled off, or plateaued, with 1 in 500 people having the virus (0.2% of the population). This represents approximately a 60% fall since the study's previous findings in February. The study also found that infections are leading to fewer hospital admissions and deaths, which likely reflects the impact of the vaccination programme.

04 March - Community infection trends in February (updated report)

Findings in brief

Our study swabbed more than 163,000 people to find out how many people currently have the virus in England, and identify those who have a greater risk of infection. The study reported that 1 in 204 people are infected, or 0.49% of the population, and that the rate of decline has slowed. The study also found that ethnic minorities, health and care home workers, people working in public transport and those employed in schools, universities, childcare and education all had a higher risk of testing positive. 

02 March - Evaluating finger-prick antibody tests

FIndings in brief

As part of the REACT-2 study, scientists evaluated the accuracy of a number of different finger-prick antibody testing kits to find out if they would be suitable for use in large-scale antibody studies.

25 February - Antibody survey and attitudes towards vaccines

Findings in brief

Our study of 155,000 people has shown that around 14% of England’s population has evidence of antibodies against the coronavirus, either from having had COVID-19 or a coronavirus vaccine. The study also looked at antibody responses in people who have had the Pfizer/BioNTech vaccine, and people's attitudes towards being vaccinated.

18 February - Community infection trends in early February

Findings in brief

The number of people infected with the coronavirus in England has dropped by over two-thirds since January. But infections are still high with around 1 in 200 people testing positive.

10 February - Identifying symptoms linked with COVID-19 

Findings in brief

Our study of over a million people revealed a wide range of additional symptoms that are linked with having the coronavirus. Among these other symptoms, chills, loss of appetite, headache and muscle aches were together most strongly linked with being infected, alongside the four 'classic' symptoms.

28 January - Community infection trends in January 2021

Findings in brief

A very high number of people were infected with the coronavirus in England three weeks into lockdown, with 1 in 64 people testing positive (1.57% of the population). 

21 January - Community infection trends in January 2021 (interim report)

Findings in brief

Coronavirus infections were not falling in the early stages of the third national lockdown in England and 1 in 63 people were testing positive with the virus.

15 December - Community infection trends during England's second national lockdown

Findings in brief

The rate of new coronavirus infections in England was found to no longer be on a downward trend and had flattened in mid-December.

30 November - Community infection trends during England's second national lockdown (interim report)

Findings in brief

Coronavirus infections were found to be declining in England at the end of November, with R below 1. 1 in 100 people were found to test positive. 

12 November - Community infection trends in early November

Findings in brief

Coronavirus infections were continuing to rise in early November but the findings suggested early signs that the rate was slowing down.

29 October - Community infection trends in early November (interim report)

Findings in brief

The infection prevalence was found to have doubled since the previous round of testing, with 96,000 new infections each day.

27 October 2020 - Trends in coronavirus antibodies in England's population

Findings in brief

Tests on more than 365,000 people in England showed that the antibody response to the virus that causes COVID-19 wanes over time.

9 October 2020 - Community infection trends in late September and early October

Findings in brief

An analysis of swab tests taken by 175,000 people between 18th September and 5th October found that the prevalence was rising with the virus infecting around 45,000 people each day.

1 October 2020 - Community infection trends in late September and early October (interim report)

Findings in brief

Infections were found to have increased substantially across all age groups and areas of the country, with 1 in 200 infected. 

11 September 2020 - Community infection trends in August and early September

Findings in brief

The study showed a reversal in coronavirus trends, with infections doubling every 7 to 8 days, compared to May and June when infections were halving every 8 to 9 days

13 August 2020 - Evaluating lateral flow tests in the lab for use in a national coronavirus antibody survey

Findings in brief

An evaluation of a number of different finger-prick antibody testing kits found that the best performing tests are suitable for large-scale surveillance studies to monitor the progress of the pandemic. These could correctly identify individuals with coronavirus antibodies over 80% of the time, while also correctly ruling out those who don’t in more than 98% of tested individuals.

12 August 2020 - Coronavirus antibody prevalence in England following the first peak of the pandemic

Findings in brief

Tests on over 100,000 people showed that slightly under 6% of the population had antibodies to the virus and had likely previously had COVID-19 by the end of June, an estimated 3.4 million people. London had the highest numbers at over twice the national average (13%), while the South West had the lowest (3%).

12 August 2020 - A study to explore how easily people can use antibody self-testing kits at home, and whether these are acceptable to the public 

6 August 2020 - Community infection trends as England exited national lockdown

Findings in brief

The research showed the prevalence of infection decreased to 0.077%, compared to May’s rate of 0.13% despite some lockdown restrictions being eased in June. 

11 July 2020 - Community prevalence of the coronavirus in England during May 2020

Tests on more than 120,000 people carried out between 1 May and 1 June, prior to the easing of lockdown, revealed that infection rates were significantly falling, dropping by half every 8 to 9 days.

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