Up to 10 million key workers and their households can now book a coronavirus test online or through their employer.
Health Secretary Matt Hancock said the expanded testing programme was “part of getting Britain back on her feet”.
The government remains some way short of its target of 100,000 tests a day in the UK by the end of this month.
Thursday’s figures showed 23,560 tests were carried out, though Mr Hancock said capacity had now increased to 51,000 per day.
The data also showed a further 616 people died with the virus in UK hospitals, bringing the total number of deaths to 18,738.
Mobile testing units
The health secretary announced the new testing arrangements at Thursday’s Downing Street coronavirus briefing, along with a commitment to recruit 18,000 people to trace contacts of those infected.
Those who can now register for a test include NHS and social care workers, police officers, teachers, those in the justice system, supermarket and food production workers, journalists and transport workers.
Previously, a smaller group of key workers – those whose work is deemed critical to the Covid-19 response – were eligible for testing.
The aim is to allow essential staff to safely return to work.
Mr Hancock said once people enter their details online they will be sent a text or email inviting them to either book an appointment at a drive-through centre or to request a home test kit, though the latter are currently in limited supply.
The website opened on Friday but has been working intermittently, with some users being greeted by an “applications closed” message.
He told BBC Breakfast the home kits would be collected by courier and would initially start in “small numbers” before the service grows.
A help desk has been established to aid the process, while mobile units run by the Army are travelling around the country to where they are needed, such as care homes.
The test involves taking a swab of the nose and the back of the throat.
Can I get a test?
Anyone classified as an “essential worker” who is showing symptoms can request a test in England and Scotland.
The list includes NHS and social care staff, teachers, police officers and transport workers.
They and their family can also request a test if someone in their household shows symptoms.
How will I be tested?
The test involves taking a swab of the nose and the back of the throat.
There are two ways to get a test: at a testing site, or with a home testing kit.
Home kits will initially be limited but are being sent to NHS staff.
Most people will get their test results by text within two days.
When can I go back to work?
Provided you and/or those in your household have not tested positive, you can go back to work.
That is so long as you are well enough and have not had a high temperature for 48 hours.
Mr Hancock has said the “majority” of people will get their result in 24 hours, but for some it might take a bit longer.
The result will be added to a person’s medical record so their doctor is informed, he added.
Key workers who are unable to access the government’s website will still be able to apply for a test, as employers are able to book on behalf of their staff.
Until now, hospitals have been carrying out tests, along with a network of about 30 drive-through centres in car parks, airports and sports grounds.
Labour’s shadow health minister, Justin Madders, told the BBC he welcomed the move to expand testing to key workers but questioned whether anything was being done to improve ease of access to the tests.
There is no doubting the scale and ambition of this project – up to 10 million essential workers and their families invited to go online if they have symptoms to book a virus test.
Ensuring the system can smoothly book people their tests at drive in centres and then get results back within 48 hours will be a major technological challenge.
Some may complain that the drive in centres are not accessible but the plan will soon involve home testing kits being sent to people to do their own swabs and send them back for laboratory testing.
The home testing kits are currently going out to NHS workers. Then government says this will be extended very soon to the wider group.
Mobile pop up test facilities will go to workplaces.
In theory this will make a big difference to key workers self-isolating because a member of their household is unwell – if that individual tests negative then others in the home can get back to work quickly.
Or if someone is unsure about their symptoms they can easily check whether they have coronavirus.
This is a significant move in the drive to boost testing.
The question now is whether the IT and the infrastructure can deliver.
The Welsh government has previously outlined plans to expand testing to key workers and Northern Ireland’s health minister has announced the nation’s testing programme is being expanded to include front-line workers in the private sector.
Scotland is prioritising tests for NHS staff.
Scotland’s First Minister Nicola Sturgeon has said England’s expanded testing system will apply to Scotland, adding she hoped it would be in place “very soon” but there were still a couple of practical issues to be solved.
Mr Hancock also detailed plans for a network of contact tracers that will be used when the lockdown is eased, insisting a process of “test, track and trace” would be “vital” to stop a second peak of the virus.
The hope is that regional outbreaks of the virus can be kept under control by isolating people with the virus, and then tracing their contacts and isolating them.
The health secretary said infrastructure would be put in place so that contact tracing can be rolled out on a “large scale”.
Prof John Newton, co-ordinator of the UK’s coronavirus testing programme, has said the government is “on track” to reach 100,000 tests a day by the end of April.
He said new types of test – including ones that do not rely on reagents which are in short supply – would help to reach the target.
Elsewhere, Mr Hancock said the plan for easing lockdown restrictions set out by Ms Sturgeon, was “very similar” to the UK government’s approach.
He said he would prefer if social distancing measures were lifted across the whole of the UK at the same time, rather than each nation changing them on their own timetable, but he also respected the “responsibilities” of devolved colleagues.
Ms Sturgeon has reiterated that the framework was published to spark a “grown-up conversation” with the public over the key factors in deciding when to lift restrictions.
She told BBC Breakfast it was “important” to be clear with the public about the thought process “because it will effect all of our lives potentially for quite a long time to come, adding that the Scottish government will release a “much more detailed plan” in the future.
She said the devolved nations and UK government were “working very well” and should “try to align our decision-making”, adding nations should have “good reasons” for taking their own separate decisions.
In other developments:
- Some lockdown rules in Wales are being made stricter to “address challenges being faced in parts of the country”, the first minister has said, including a clamp down on the use of second homes
- Baroness Doreen Lawrence has been appointed as the Labour party’s race relation adviser and will lead a review into the impact of coronavirus on BAME communities amid concerns the virus may be disproportionately impacting them
- Gatwick Airport has said it expects it will take up to four years for passenger numbers to return to recent levels once the coronavirus pandemic recedes
- US President Trump has said Prime Minister Boris Johnson sounded “sharp and energetic” in a phone call on Tuesday.
- The first human trial in Europe of a coronavirus vaccine has begun in Oxford – with the first two volunteers being injected
- Stars and royals raised more than £27m on BBC One charity special The Big Night In
- Tobias Ellwood, Conservative chair of the defence select committee, said the government has been “too slow in procuring the necessary” personal protective equipment for frontline staff
- A submarine crew were filmed having a party during the coronavirus lockdown, prompting a Royal Navy investigation
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