Britain will face "further waves" of Covid-19 and will probably have the highest death rate in Europe because the Government was "too slow" to act, a leading physician has warned.
Professor Anthony Costello, of University College London's Institute for Global Health, told a committee of MPs that the "harsh reality" is that "we were too slow with a number of things" and deaths could reach to 40,000.
His comments came as the Department of Health said a total of 14,576 patients have died in hospital after testing positive for coronavirus in the UK as of 5pm on Thursday, up by 847 from the day before.
Prof Costello said: "If we're going to suppress the chain of transmission of this virus in the next stage we all hope that the national lockdown and social distancing will bring about a large suppression of the epidemic so far - but we're going to face further waves."
"And so we need to make sure that we have a system in place that cannot just do a certain number of tests in the laboratory, but has a system at district and community level."
Prof Costello, giving evidence to the Commons Health and Social Care Committee, said we "should not have any blame at this stage" but that "we can make sure in the second wave we're not too slow".
Health Secretary Matt Hancock announced that testing will be expanded to those in the police, fire service and prisons, as well as critical local authority workers, the judiciary and Department for Work and Pensions staff where required.
It follows criticism of a gulf between those being tested and the testing capacity, with just 18,665 tests being conducted in the 24 hours up to 9am on Thursday, despite 38,000 tests being available.
Mr Hancock confirmed to the committee that more than 50,000 NHS workers have now been tested for coronavirus, and admitted he would "love to be able to wave a magic wand" to increase supplies of personal protective equipment (PPE).
MPs were also told that healthcare staff are "genuinely concerned" about the safety of patients being compromised if workers are spread too thinly.
Dr Alison Pittard, Dean at the Faculty of Intensive Care Medicine, said: "We've had to spread ourselves more thinly and we have developed guidance to try and make sure that continues to be safe, but if we have to expand even more and spread ourselves even more thinly, there would be concern that safety could be compromised.
"So everyone is working really well, we're doing everything that we can but staff are genuinely concerned."
Dame Donna Kinnair, chief executive of the Royal College of Nursing, told the committee sick NHS workers are being forced to drive two hours away to be tested.
She urged: "We need some really clear direction on how we can access testing both in the NHS but more so for social care, because they don't have the same infrastructure as the NHS."
Prof Costello, a former British director at the World Health Organisation, said he was "not sure we need 100,000 tests per day in reality if we can get this epidemic damped down" and that it was "more important to have the systems in place".
"How are they restructuring the public health teams? Have they got plans in place?
"Will they need extra volunteers, for example?"
He also suggested offering incentives to 10% of the population to stay socially isolated in order to get the economy going again.
"We have to get the economy going and if it means locking down 10% of our population, even giving them incentives to stay in quarantine and with digital apps to help monitor their symptoms and give them support, that's the way to really keep this going until we get a vaccine and safe herd immunity."
The committee's chairman Jeremy Hunt later called for "a massive ramp-up - not just in the testing, but also the tracing of everyone who has been in contact with someone who has the virus".
He told BBC Radio 4's World At One programme: "If we're going to be in a position where we can track and trace every single person who has Covid or might have had Covid in three weeks' time, because that's when we could next potentially end the lockdown, well that is a huge logistical undertaking."
Mr Hunt added: "If we're going to copy the best in the world then that is what we now need to do."
Elsewhere, Downing Street said it was "wrong" of Labour leader Sir Keir Starmer to suggest the Government is not being more forthcoming about an exit strategy because Boris Johnson is absent.
Dominic Raab, who is deputising for the Prime Minister, spoke to Mr Johnson on Thursday, Number 10 confirmed.
The PM is said to be "continuing his recovery at Chequers" and "not doing Government work".
