Real-time Assessment of Community Transmission (REACT) Study

About the REACT programme

Launched in April 2020, the REACT programme began as one of the world’s largest and most comprehensive coronavirus monitoring studies. The programme is led by a world-class team of researchers at Imperial College London in partnership with Ipsos MORI and commissioned by the Department of Health and Social Care.

Since it began, the study has evolved and expanded. While the REACT 1 and REACT 2 studies focused on home testing to track the progress of England’s epidemic, our more recent work, carried out as part of the REACT-Long Covid (REACT-LC) study, uses the population level sample from the original REACT studies to investigate the biological, environmental and social factors that determine why some people experiences persistent symptoms after Covid-19

A significant feature of the REACT study is data linkage. People in the REACT studies have given their permission for us to link their survey data to health data held by NHS England and other NHS bodies. For these 2.7 million adults the REACT study now holds information about their short- and medium-term health, including when they use NHS healthcare, what they are diagnosed with and their prognosis. We are using this information to understand more about the natural history of SARS-CoV-2 infection, including asymptomatic infection, Long COVID, hospitalisations and deaths. We are also studying the effectiveness of vaccination and other interventions and exploring inequalities in long-term outcomes following COVID.

If you have been invited to take part in our latest questionnaire please visit the Health and Wellbeing Questionnaire page