The British firm behind a cheap DIY coronavirus test which is 'almost 100 per cent accurate' claims its offer to mass produce them for the NHS has fallen on deaf ears.

Boris Johnson promised to buy hundreds of thousands of 'antibody tests' which can tell if a person is currently suffering from coronavirus or has ever had it in the past.

The Government has warned it could take weeks or months to roll them out because current ones on the market are not reliable enough, it claims.

Derby-based SureScreen Diagnostics says it has created a finger prick test that takes just 10 minutes to give a diagnosis and is correct 98 per cent of the time.

The £6 test detects antibodies, the immune system's defence mechanism, which are produced to fight off the killer virus.

By measuring antibodies in the blood, doctors can detect whether someone has had the infection previously and is now immune to catching and spreading it.

MailOnline reported earlier this week the test was being used by private firms on more than 180,000 people globally, in countries including Germany, Spain, Switzerland and the Netherlands.

Public Health England said Brits should avoid using it because there is 'little information on the accuracy of the test'.

SureScreen claims it has the capacity to make half a million tests a week to meet Boris Johnson's ambitions plan to screen hundreds of thousands of people a day.

The pharmaceutical company said it had 'done its best' to reach out the health officials but had heard nothing back.

SureScreen Diagnostics says it has developed a finger prick test that takes just 10 minutes to give a diagnosis and is correct 98 per cent of the time

The private firm says its test has been validated and is already being used in the Germany, Spain, Switzerland, Netherlands, Turkey, UAE, Kuwait and Oman

Users then put their blood sample in a screening device and results are displayed in a similar fashion to an at-home pregnancy test within minutes

One of SureScreen's directors, David Campbell (pictured), said the product could 'probably save the NHS a lot of money' and drastically reduce the number of infections

But despite PHE's warnings, the finger prick test has been used by private healthcare companies across Europe, the Middle East and Australia.

One of SureScreen's directors, David Campbell, said the product could 'probably save the NHS a lot of money' and drastically reduce the number of infections.

HOW DOES THE FINGER PRICK TEST WORK? Derby-based SureScreen Diagnostics says it has created a finger prick test that takes just 10 minutes to give a diagnosis and is correct 98 per cent of the time. The £6 test detects antibodies, the immune system's defence mechanism, which are produced to fight off the killer virus. By measuring antibodies in the blood, doctors can detect whether someone has had the infection previously and is now immune to catching and spreading it. Suspected patients can be posted the test and use the finger pricker to extract a blood sample themselves. Users then put the sample in a screening device which then takes a few minutes to scour for antibodies that have been released by the immune system to fight coronavirus. They are then given a positive or negative result, similar to how an at-home pregnancy test works. Those who test positive will have already been infected - sometimes without knowing or showing symptoms - and are likely to be immune to reinfection. The test can only detect people who have been infected with coronavirus for three days or more. After 33 days the antibodies drop to undetectable levels but the body now knows how to produce them now so patients remain immune to the virus. The tests would be a game changer because they help work out who is safe to resume normal life without fear of contracting or spreading the virus. Advertisement

Mr Campbell said: 'Unfortunately, we haven't really been able to get much traction in the UK with the NHS – which seems a bit of a shame.

'We're sending it abroad and we're not able to use it here to really help reduce the number of infections.

'We've done all the clinical work behind this test, we believe it has a really great part to play in terms of doing large amounts of screening to really help control the infection and get that data on where exactly this infection might break out.'

'I suppose our message to the Government is, "We're here and happy to do any trials and things like that to prove the accuracy."

'We've done them all ourselves already but we'd like to engage with partners to do trials in the UK as well.

'We're here to do what we can to reduce the spread of infection. We've done our best to engage with the Government and the NHS.'

The antibody test comes with a finger pricker which suspected patients use to extract a blood sample.

Users then put the sample in a screening device which then takes a few minutes to scour for antibodies that have been released by the immune system to fight coronavirus.

Users are then given a positive or negative result, similar to how an at-home pregnancy test works.

Those who test positive will have already been infected - sometimes without knowing or showing symptoms - and are likely to be immune to reinfection.

The test can only detect people who have been infected with coronavirus for three days or more.

After 33 days the antibodies drop to undetectable levels but the body now knows how to produce them now so patients remain immune to the virus.

The tests would be a game changer because they help work out who is safe to resume normal life without fear of contracting or spreading the virus.

Mr Campbell added: 'We've had a range of tests looking at infectious diseases for many years.

Speaking at his daily national address yesterday, Prime Minister Boris Johnson announced the first British patient had been put into a clinical trial of a potential coronavirus therapy - the Government has so far refused to reveal details of the trial

Row over testing WHAT IS THE UK DOING NOW? Around 5,000 tests are being carried out a day. Those are mostly patients who are already in hospital. Some 100 GP surgeries have agreed to carry out tests on patients, as part of surveillance to asses the prevalence. However, those who feel they have symptoms are being told to self-isolate without being routinely tested. WHAT IS THE UK GOING TO DO? Boris Johnson has vowed to increase tests to 25,000 a day, although he did not give a timescale. He also said that health workers will be prioritised. Many have complained that they are being forced to stop work as they are unsure whether or not they have the disease. WHAT DO THE EXPERTS SAY? The message from the World Health Organisation is 'test test test', to avoid trying to fight an outbreak 'blindfolded'. South Korea says it has got on top of an outbreak with stringent testing. Advertisement

So when we saw the coronavirus had started in China, the likelihood was it would spread quite quickly due to the long incubation time – so we set about developing a test for coronavirus.

'We're looking for two specific bi-markers which are elevated in people once they've contracted the infection and the test can be used in 10 minutes at the patient's side very quickly, accurately and cost-effectively – giving you a result straight away and alleviating a lot of the issues you've got with people walking around not knowing they've got it.'

'With this test you can pick people up three days after infection so that's very important to know people have or have not got the infection.

'It also alleviates the issue of self-isolation when they might have a cold or something like that and now you can test yourself to see if you've got coronavirus or not.

'As you can imagine, a test like this which gives you results by the patient's side very quickly and accurately has been hugely popular.'

The Department of Health has been contacted for a comment.

The Government's chief scientific adviser said it could take weeks for antibody tests to be available on the NHS because ones on the market were not reliable enough.

Speaking at a press conference in London yesterday, Sir Patrick Vallance said: 'Everyone's looking for a serological test. They've got some in some parts of the world.

'There are two types, one that requires a laboratory testing and the other is an easy to use thing that you can use yourself at home.

'Currently we're looking at both of those, but you've clearly got to have reliability. That's the first thing. There's a danger that you have something that isn't reliable enough.'

Sir Patrick added the tests were being worked up 'as we speak'. He said: 'If you can get to mass testing, which would definitely be the idea, then that does become very useful.

Two men wearing suits were pictured carrying a box from ThermoFisher – which makes coronavirus tests that give results in four hours – outside Downing Street this week to discuss buying the tests

TESTING STOPPED THE VIRUS IN A SMALL ITALIAN TOWN Italian authorities have managed to contain the killer coronavirus outbreak in a small town near Venice through a rigorous testing strategy. Health bosses in Vò – 45miles (72km) east of the tourist hotspot – have had no new cases for 48 hours. Officials conducted an experiment in the town, which is home to 3,300 people, to test and re-test all inhabitants. The Financial Times reports the strategy meant everyone would be tested – even if they showed no symptoms. Andrea Crisanti, an infectious disease specialist taking part in the experiment, told the newspaper the method allowed officials to get the clearest picture about the size of the outbreak. The experiment began at the end of February, and the initial roll-out of tests showed around three per cent of patients were infected. This dropped ten-fold when the second testing round was carried out 10 days later, after quarantining all of the infected and their contacts. Professor Crisanti, who is on a sabbatical at the University of Padua, said: 'In the UK, there are a whole lot of infections that are completely ignored. 'We were able to contain the outbreak [in Vò] because we identified and eliminated the 'submerged' infections and isolated them. This is what makes the difference. Advertisement

'It answers the question of what proportion of patients are asymptomatic, a really important unknown in this.

'Secondly it can tell you who's had it and developed an antibody against it and therefore won't catch it again.'

The tests would first be used on healthcare workers, who are essential in the fight against the virus.

Sir Patrick added: 'That then becomes important in understanding who's safe to go back and start working. Gives much greater flexibility in terms of the NHS.'

'We shouldn't dream that you can scale up hundreds of thousands of tests in a day. You can't... it doesn't happen overnight. It won't be in a few days.'

At the moment, only around 5,000 tests are being conducted in the UK every day - mostly hospital patients and elderly people.

Britain is still using nasal swabs which take up to 48 hours to produce results, often leaving suspected patients in limbo.

It means the average person is not able to find out if they have coronavirus even if they have all the tell-tale symptoms.

But the Prime Minister assured the country yesterday that he was doing all he could to secure the antibody tests.

He said: 'We're in negotiations today to buy a so-called antibody test, as simple as a pregnancy test, which can tell whether you have had the disease.

'It's early days, but if it works as its proponents claim, then we will buy literally hundreds of thousands of these kits as soon as practicable.

'It has the potential to be a total game-changer.'

In the UK and around the world, hopes are also growing that a drug cure for Covid-19 can be found - with promising results from several existing experimental treatments.

Meanwhile the Government's health agency said trials of a coronavirus vaccine could begin within the next month, as it prepares to start evaluating a drug developed by Oxford University.

Scientists at Public Health England (PHE) could give the go-ahead for human testing well ahead of the usual time frame for drug development.

The health agency is only due to start preliminary evaluation of the vaccine on animals next week.

PHE researchers have collaborated with teams at Liverpool and Bristol universities to create an exact replica of Covid-19 for use in the testing process.

Those behind the vaccine have been given permission to commence human trials before animal tests are complete, the Guardian reported, in a bid to accelerate the development process.

Permission was granted after similar vaccines developed for other diseases were proved safe in human trials.

Professor Adrian Hill, head of the Jenner Institute at Oxford, told the Guardian: 'We are conscious that a vaccine is needed as soon as possible and certainly by June-July when we expect a big peak in mortality.

He added: 'This is not a normal situation. We will follow all standard trial safety requirements but as soon as we have a vaccine that's working we anticipate there will be an accelerated pathway to get it deployed to save lives.

'The more vaccine we can provide the sooner the better.'

The team at the Jenner Institute only began work on the drug on January 10 this year.

Earlier this month, Anthony Fauci, the director of the US's National Institute of Allergy and Infectious Diseases, said he expected it would be at least 12 to 18 months before a coronavirus vaccine is widely available.

The Jenner Institute said it had based the drug on an 'adenovirus vaccine vector' based on an adenovirus isolated from a chimpanzee.

An adenovirus is a group of viruses that typically infect membranes of the eyes, respiratory tract, urinary tract, intestines and nervous system.