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Coronavirus: Estimated speed of coronavirus infections rises over past week

Scientists have said the UK reproduction number for COVID-19 is now between 0.7 and 1, up from 0.5 to 0.9 last week.

Government scientists consider hospital admissions in determining the speed of infection

The official estimate of the pandemic "R" number has risen slightly over the last week, according to a consensus by scientists advising the government.

The Scientific Advisory Group for Emergencies (SAGE) said the UK reproduction number for the coronavirus is now between 0.7 and 1, up from 0.5 to 0.9 last week. The slight increase, based on calculations done by six research groups, is being attributed to cases in care homes and hospitals accounting for a greater proportion of the overall total.

It is too soon after the easing of the lockdown for increased movement of people to show up in the data. Hancock: 'R' rate 'not likely' to be above 1 R is a measure of how fast a virus is spreading. Above 1 an outbreak is growing; the further below 1 the faster it's shrinking. It's estimated using data from hospital admissions, intensive care demand, deaths and the number of social contacts people have. Health Secretary Matt Hancock said the R number was based on data from around a fortnight ago and he did not believe the figure was above one. Speaking at the government's daily news briefing, he said: "We are constantly keeping the R under review. We don't think that it is above one. So that meets that test."

He told Sky News: "On the timing, this is based on data from a couple of weeks ago because of the way it is measured but also from the survey data that the ONS (Office for National Statistics) has published. "It is an incredibly important figure for policymakers but it is one data point to look at alongside the level of new cases." Deputy chief medical officer Dr Jenny Harries said: "R is a very standard way of looking and comparing what is happening and it's a really important measure.

"But the real outcome we are looking for is the reduction in the number of cases and getting rid of the epidemic in the UK so that is our focus, not R. "

"R is a representation of what is happening in that fight".

'There's always an opportunity in a crisis' SAGE is currently trying to calculate regional R numbers to reflect higher transmission in the North East and Scotland and lower rates in London.

A modelling study by Public Health England and the Cambridge MRC Biostatistics Unit has concluded that the R number in London could be as low as 0.4, with an estimate of just 24 new cases a day.

But government scientists are understood to be sceptical that the number of new infections is that low. There were 49 patients admitted to hospitals in London yesterday.

For every admission there are likely to be 20 other cases in the community - bringing the total number of new infections closer to 1,000.

The Department of Health confirmed another 384 coronavirus-related deaths were recorded in the UK on Thursday, bringing the total number 33,998.

Estimates of the R number are notoriously difficult because of the lag between the point at which people are infected and the time that data is collected. For example it takes roughly 10 days for people to become sick enough to need hospital care. The prime minister has said that easing the lockdown will depend on both the R number and the number of new infections.

The lower the number of daily cases, the easier it will be to trace their contacts and stop flare-ups of the virus.



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