Health officials say they are “frustrated” by a lack of progress in expanding UK coronavirus testing.
Prof Paul Cosford of Public Health England (PHE) said “everybody involved” is unhappy testing has not “got to the position yet that we need to get to”.
Prime Minister Boris Johnson responded to criticism of the UK’s strategy by hailing screening as a solution to “unlock the puzzle” of coronavirus.
It came after the UK saw its biggest daily increase in deaths – 563.
As of 17:00 BST on Tuesday, the overall number of deaths from the virus in the UK was 2,352.
Mr Johnson, who is self-isolating in Downing Street after contracting the virus himself, has faced widespread criticism over his government’s testing strategy – with around 13,000 tests available each day against a target of 25,000.
Prof Cosford said testing would hit 15,000 per day “imminently” and that PHE had played its part in ensuring tests were “available to support clinical treatment of patients who need it”.
The government has confirmed that 2,000 NHS frontline staff out of half a million in England have been tested for coronavirus since the outbreak began.
Prof Cosford, PHE’s emeritus medical director, told BBC Radio 4’s Today programme the figure was “nowhere near where we need to get to but it’s a good start”.
But Labour’s Shami Chakrabarti said the slow pace of testing showed “a lack of clarity of what the plan is and how it is going to be executed”.
Sir Paul Nurse, chief executive of the Francis Crick research institute – which will soon be able to conduct 500 Covid-19 tests a day – said a Dunkirk-style effort was needed to co-ordinate smaller laboratories and increase test numbers.
“We are a lot of little boats and the little boats can be effective,” he said, referring to the Second World War evacuation of Allied troops from the beaches of the French city.
He added: “The government has put some big boats, destroyers in place. That’s a bit more cumbersome to get working and we wish them all the luck to do that, but we little boats can contribute as well.”
In a video message on Twitter on Wednesday evening, Mr Johnson said that increased screening would be how the UK defeats the coronavirus.
“I want to say a special word about testing, because it is so important, and as I have said for weeks and weeks, this is the way through,” he said.
“This is how we will unlock the coronavirus puzzle. This is how we will defeat it in the end.”
Mr Johnson said more coronavirus testing would enable staff who were self-isolating – either because they had symptoms or shared a household with someone who was sick – to know if they were safe to work.
Antibody tests – which look for signs of immunity in the blood – could also show who had already had coronavirus and was therefore not at risk of being infected or passing the infection on to others, the prime minister said.
However, these tests are not yet ready for use and it is not clear when they will be.
On Wednesday, Dr Yvonne Doyle, Public Health England (PHE) medical director, said during Downing Street’s daily coronavirus briefing that the “intention” was for testing for frontline staff to increase from “thousands to hundreds of thousands within the coming weeks”.
The prime minister’s official spokesman said the government was working with NHS England, Public Health England and other organisations to boost test capacity with an additional network of labs and testing sites.
Health Secretary Matt Hancock has held talks with industry figures, issuing what his department said was a “rallying call” to improve diagnostic capability.
However, some NHS trusts have said they are limited in the number of tests they can carry out due to continued shortages of swabs, reagents and testing kits.
One large English district hospital in the Midlands reported it was only able to test three staff members per day due to a lack of swabs, NHS Providers said.
Another trust in the West Midlands said that while it could carry out up to 300 tests per day, a shortage of reagent and testing kit availability meant only 20 were carried out daily.
Despite there being capacity for 12,750 daily tests, only 8,630 were taken on Monday, the prime minister’s official spokesman said.
As of 9:00 on Wednesday, 152,979 people in the UK had been tested for the virus with 29,474 confirmed positive.
Meanwhile, Addenbrooke’s hospital in Cambridge has become the first in the UK to use a new, much quicker Covid-19 test for staff and patients.
Called Samba Two, it gives a result in just 90 minutes – as opposed to the 24 hours tests currently take – and has been adapted from an HIV test by a small Cambridge technology company.
Businessman and philanthropist Sir Chris Hohn, who is helping make the test more widely available, told the BBC it could be a “game-changer” in helping hospitals cope with the crisis.
In other developments:
- Loan and credit card payments could be frozen to support those struggling as a result of the coronavirus pandemic
- British Airways is expected to announce it will suspend around 36,000 staff due to the crisis
- Some 950,000 new universal credit claims were made in just two weeks from the middle of March – the normal figure for a two-week period is 100,000
- A third prisoner in the UK has died after contracting coronavirus at HMP Littlehey in Cambridgeshire
- Up to 3,000 armed forces reservists have been called up to aid the military response to the coronavirus pandemic
- The Treasury is to announce changes to its emergency loans scheme for businesses by the end of the week – after thousands of struggling companies had their applications turned down
- Defence Secretary Ben Wallace has become the fourth cabinet minister to self-isolate
- NHS 111 has responded to more than 1.7 million inquiries over the past 15 days from people concerned they might have symptoms of coronavirus
- Wimbledon is cancelled and Uefa has suspended all Champions League and Europa League matches “until further notice”
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