The UK death toll from coronavirus is likely to be far larger than that shown by official figures, experts have said.
Until now, daily figures – which reveal 1,415 UK deaths so far – have only counted those in hospital, and show a growing time lag approaching three weeks in some cases.
On Tuesday, the Office for National Statistics will release data for England and Wales which should include any death linked by doctors to coronavirus, regardless of where the person died.
Officials are braced for an increase in deaths, but expect a far sharper rise in the coming weeks because even Tuesday’s figures have a time lag of 11 days from the point a death is officially registered.
The development comes as the number of people being treated in hospital for coronavirus doubled in less than a week. Sir Simon Stevens, the head of the NHS, said on Monday that more than 9,000 patients are in hospital with Covid-19 – up from 4,300 on Thursday.
Every day, NHS England releases figures showing the number of new deaths and the total number of confirmed deaths reported. But a growing time lag reporting such cases means the new data from the NHS included deaths that date back to March 13.
It comes after an email to staff at King’s College Hospital Trust in London disclosed that 31 patients had died from Covid-19 over a six-week period, but that official figures had only recorded 11 of them.
The deputy chief medical officer, Dr Jenny Harries, said there was a time lag in the number of deaths tallied up as officials firm up the numbers and speak to families.
It raises the prospect that Britain could be following the deadly trajectory seen in Italy, which has now seen more than 10,000 deaths.
One Government source said: “We do expect to see an increase in the figures [on Tuesday]. It may be a significant one, but it is important to remember these are including suspected cases as well as positive cases.”
It came as 1,408 people were confirmed to have died in UK hospitals after testing positive for Covid-19 as of 5pm on Sunday, up 180 from 1,228 the day before.
Earlier, the head of the Royal College of Physicians said around one in four NHS doctors are off work sick or in isolation.
The figures due on Tuesday are based on the number of deaths registered “where Covid-19 is mentioned anywhere on the death certificate”, the ONS said. They will cover all deaths for the week ending March 20, although it normally takes around five days for a death to be registered, adding to the lag.
There is also normally a five-day delay in registering a death, which means the new weekly ONS tally could lag behind other data.
On Monday Sir Patrick Vallance, the chief scientific adviser, said Tuesday’s figures would see some “extra numbers” on deaths, but he did not expect the rise to be large. He added that there would always be a time lag on deaths data, but stressed that health officials were “working very hard to close that gap”.
The UK’s latest figures show 22,141 cases of coronavirus, but this is widely believed to be an underestimate because most people with symptoms are not offered testing.
Overall, this winter has seen death rates lower than those of last year. But overall death numbers began to rise in the week ending March 13 – the week after the first coronavirus death was reported in the UK – with 11,019 deaths, up 452 on the same seven days last year.
An ONS spokesman said the number of deaths had been lower over the past few months “in part due to the mild winter”.
Number 10 said some of the time lag in reporting cases was in order to alert victims’ families to the inclusion of their death in the statistics.
The Prime Minister’s official spokesman said: “There is a need for families who are grieving to have been told that a loved one will be included in the statistics before they are released. In some circumstances, that has led to a small delay in some individuals being included in the numbers.”
“You are seeing details of all deaths which take place in hospital – the issue would be around whether or not there may be a day’s delay while you ensure that a family member knows that a loved one is going to be quoted in the statistics.”