Imperial College London

Coronavirus infections remain high three weeks into lockdown - REACT study

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A sign in the street

A very high number of people have the coronavirus in England with around 1 in 64 people infected, or 1.57% of the population.

These latest findings from the REACT programme – the biggest and most comprehensive study of community coronavirus testing – are based on swab samples from almost 170,000 people taken between 6th and 22nd January. 

In a new report, researchers from Imperial College London estimate R to be around 1, which means that the epidemic is not clearly growing or shrinking and will continue at this high level if the situation doesn’t change. However throughout this round of data collection, patterns of infection have been fluctuating at the national level, with signs of a slight upward trend in the first 10 days – shown in an interim report published last week – followed by a slight decline in the last seven days. 

"If infections aren’t brought down significantly, hospitals won’t be able to cope with the number of people that need critical care." Prof Paul Elliott School of Public Health, Imperial

This would suggest that lockdown has curbed the steep rise in infections, although the researchers caution that the country isn’t experiencing the fast rate of decline that happened during the first lockdown. This could be partly explained by the new variant which spreads more easily, alongside other factors such as more people going to work and a higher number of children in school. 

There is also a lot of variation across England, with some regions like the South West experiencing a drop in infections, whereas others such as the East Midlands are showing evidence of a rise. Some age groups are also worse affected than others, with those aged 18-24 having the highest number of infections at 2.44%, or 1 in 40.

Professor Paul Elliott, director of the programme at Imperial, said: “The number of people infected with the virus is at the highest level that we’ve recorded since we began testing last May. We’re not seeing the sharp drop in infections that happened under the first lockdown and if infections aren’t brought down significantly, hospitals won’t be able to cope with the number of people that need critical care. We all need to stay at home wherever possible and help bring the virus under control and protect our already over-stretched health system.”

These findings from the ongoing REal-time Assessment of Community Transmission (REACT 1) programme, led by Imperial and carried out in partnership with Ipsos MORI, are available in a pre-print interim report and will be submitted for peer-review.

Coronavirus infection trends

Out of 167,642 swabs taken for this testing round, 2,282 were positive giving an overall prevalence of 1.57% or 157 per 10,000 infected. This is the same rate as the interim findings reported last week, which looked at the first 143,000 swabs taken in this study round. 

The national R number – the average number of people an infected individual will pass the virus onto – was estimated to be 0.98 for this round of testing with a possible range of 0.92 to 1.04. 

"REACT offers a highly detailed and reliable picture of what is happening at a specific point in time." Prof Steven Riley study author, Imperial College London

Regionally the study has revealed differences in patterns of infection. The number of people testing positive was dropping in the South West and there was some evidence of a recent fall in London and South East. Whereas infections were growing in the East Midlands and may also be rising in the West Midlands and Yorkshire and the Humber.

London remains the worst affected area with 2.83% of the population infected, or 1 in 35. 

Professor Steven Riley, study author and Professor of Infectious Disease Dynamics at Imperial, said: “REACT is one of several large studies tracking England’s epidemic and its strength is that it offers a highly detailed and reliable picture of what is happening at a specific point in time. Although these programs collect data in different ways and as a result may sometimes show slightly different trends, they are all pointing to the same overall conclusion; right now the prevalence of infection is very high.”

Identifying groups at risk

Young people aged 18-24 had the highest risk of infection where prevalence was found to be 2.44%, or 1 in 40 infected. In London this rose to 1 in 25, where people aged 13-17 also had the same infection prevalence (4%). London also had the highest number of infections in people aged 55 to 64 and 65 and above, with 1 in 50 testing positive (2%).

Health and Social Care Secretary Matt Hancock said: “These findings are a stark reminder of the need to remain vigilant. Infection rates this high will continue to put a strain on our NHS and add to the significant pressures dedicated health and care staff are already facing.

“We must bring infections right down so I urge everyone to play their part to help save lives. You must stay at home unless absolutely necessary, follow social distancing rules and minimise contact with others.”

"While we do see the suggestion of a downturn in the last few days of the study, which is encouraging, this is only tentative." Kelly Beaver Ipsos MORI

People living in poorer neighbourhoods, ethnic minorities and those living in large households were also found to have a higher risk of infection, as were key workers.

Kelly Beaver, Managing Director - Public Affairs at Ipsos MORI, said: “In the latest REACT snapshot across Round 8 we continue to see very high levels of COVID-19 at a national level, which continues to be worrying. While we do see the suggestion of a downturn in the last few days of the study, which is encouraging, this is only tentative. REACT continues to provide a powerful look across England at prevalence and spread of the pandemic and I thank all of the over 160,000 people who have taken part in this round for helping us provide this insight to Government.”

Understanding levels of infection in the community

The REACT 1 study is tracking current coronavirus infections in the community by testing more than 150,000 randomly-selected people each month over a two-week period. The study recruits new people each month to help ensure the sample represents the wider population and offers a high-resolution snapshot of the situation across a particular time period. This is different from the ONS COVID-19 Infection Survey which runs continuously and samples the same people over time to understand household transmission. Because the studies use different methods, this means that sometimes they report different figures. 

People who volunteer for REACT take throat and nose swabs at home, which are then analysed in a laboratory by a technique called RT-PCR. These findings are helping guide public health measures so that the Government can better respond to the pandemic as the situation evolves.


Download the report here.

Reporter

Justine Alford

Justine Alford
Institute of Global Health Innovation

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Contact details

Email: press.office@imperial.ac.uk
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