COVID: how to make sense of the UK's new testing rules.
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Significant delays in providing PCR test results in some areas have seen people wait up to five days to find out if they have Covid, leaving many in limbo in the run up to Christmas. PCR test results are generally expected to take no longer than two days according to the Government website, but anecdotal cases have emerged of people waiting longer than expected for their results.
One person was told by a Test and Trace call handler not to chase for PCR results until 72 hours after the test has been taken. She finally received a negative result on Monday. He relies on coming to my house and spending time with my dogs for company so I was worried about him basically.
There are fears that the slower pace runs the risk of people who are unknowingly positive continuing to mix with others and potentially spreading the virus further. Care home worker, Carly Burgh also took a PCR test last Thursday and waited five days before finally receiving her results on Tuesday morning. Log In. Contact us Sign up for newsletters. By Maria Collinge.
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Why are pcr tests taking so long uk
Why are pcr tests taking so long uk.Airports call Government to remove 'unnecessary' Covid tests - UK ‘lagging’ behind Europe
Coronavirus antibody tests which reveal exactly who has had the infection and is likely to be immune are said to be crucial for phasing countries out of lockdown. Germany , Italy , Finland and the US have all launched large-scale antibody testing programmes in recent weeks as they look to get society up and running again.
South Korea - one of the few countries to flatten its curve without social restrictions -today became the latest country to scale up production of its antibody tests. But the British Goverment has refused to approve any antibody test, claiming they give a 'false positive' too often when they incorrectly tell people they are immune.
This is 'dangerous' because it might give people the false confidence to resume normal life and risk catching the bug, according to Chief Medical Officer Chris Whitty. The UK last months made a provisional order for But researchers at the prestigious university found none of them were reliable enough to be rolled out to the masses.
Included in the Officials are now scrambling to try to get that money back. It comes as Swiss pharmaceutical giant Roche announced it would be launching a 'highly specific' antibody test by early May.
Roche - one of the 'big four' diagnostics companies in the world - said it will be able to manufacture 'double-digit millions' of the devices by the end of June. While Roche did not specify how the tests will work, it is thought samples will need to be processed in a lab and will not be suitable for use at home.
South Korea, one of the few countries to flatten its curve and not impose social restrictions, today became the latest country to scale up its production of antibody tests shown. The proactive move comes as South Korea looks to eradicate the virus completely after reporting around just 20 new cases for the fourth day in a row. An at-home coronavirus antibody testing kit being sold in pharmacies in Germany. They are not regulated in the EU country yet but are being trialled on a large scale.
The Canea Schnelltest comes with a finger pricker, sterilising wipes and a small screening device. Essex-based firm BioSure has developed a DIY antibody test, with the company now racing to make it reliable enough to pass validation.
An antibody test detects if someone has previously had coronavirus and has since recovered, even if they are unaware they were infected. There are two different types of antibody tests - one which is done at home and takes a few minutes, and another which is posted to a lab to be analysed. Both versions of the test are carried out using a finger pricker to extract a blood sample. People using the DIY home tests place their sample in a screening device which takes a few minutes to scour the blood for antibodies.
These are substances created and stored by the immune system when someone gets ill. If a person has COVIDspecific antibodies, it means they have already defeated the virus and are likely to have gained some immunity to it. The antibody tests - also known as 'serological tests' - were described as a 'game changer' by Prime Minister Boris Johnson last month. As well as painting a clear picture of who is safe to return to work, they are convenient and cheap. An antibody test is one which tests whether someone's immune system is equipped to fight a specific disease or infection.
When someone gets infected with a virus their immune system must work out how to fight it off and produce substances called antibodies. These are extremely specific and are usually only able to tackle one strain of one virus. They are produced in a way which makes them able to latch onto that specific virus and destroy it. The body then stores versions of these antibodies in the immune system so that if it comes into contact with that same virus again it will be able to fight it off straight away and probably avoid someone feeling any symptoms at all.
To test for these antibodies, medics or scientists can take a fluid sample from someone - usually blood - and mix it with part of the virus to see if there is a reaction between the two. If there is a reaction, it means someone has the antibodies and their body knows how to fight off the infection - they are immune.
If there is no reaction it means they have not had it yet. Antibody tests differ to a swab test, known as a PCR polymerase chain reaction test, which aims to pick up on active viruses currently in the bloodstream. This DNA can then be scanned to find evidence of the virus's DNA, which will be embroiled with the patient's own if they are infected at the time.
The PCR test is more reliable but takes longer, while the antibody test is faster but more likely to produce an inaccurate result. It does not look for evidence of past infection. They work like a home pregnancy test, giving a 'positive' or 'negative' result within 10 to 15 minutes.
Antibody tests differ to a swab test, known as a PCR polymerase chain reaction test, which the Government currently uses. Saliva samples have to be sent to a lab where scientists scan the DNA for evidence of the virus. The PCR test is more reliable but takes longer - up to two days - while the antibody test is faster but more likely to produce an inaccurate result.
The Government promised weeks ago that they would be rolled out en-masse. Britons were told they would be able to buy them from Amazon or Boots. By comparison, Germany is trialling the tests on tens of thousands of its population. Last month, the UK Government ordered 3. Later it announced it had placed provisional orders for Among them were two tests made by Chinese companies. But the deals were on the condition that they could pass reliability tests by scientists at Oxford University.
Researchers at the prestigious university did not approve any of them, meaning it could now be months before they are used in the UK, if at all. The tests were said to give 'false positive' results too often, meaning they incorrectly tells people they are immune. This might give people false confidence that they can't catch the bug and put them at risk of infection.
After being stung by the faulty Chinese antibody tests, the UK Government is said tonow be looking for 'home grown' devices made by British firms. The UK, along with every other country in the world, is still trying to find a test which can be mass produced which shows if someone has had the disease and now has immunity to it.
However, when the antibody tests were put through their paces they were found not to be sufficiently accurate and as a result could not be used. The spokesman said: 'Where tests are shown not to have any prospect of working then we will seek to recover as much of the costs as we can.
Officials have previously insisted that they had only purchased the minimum number of antibody test needed to conduct initial trials with full orders contingent on the kits actually working. But UK-based manufacturers are struggling to access blood samples of infected patients to trial their devices on. It is now calling for blood donations from members of the public who were either diagnosed with, or were suspected of having, the virus.
No country has successfully implemented a nationwide antibody testing programme. Germany became the first in Europe to carry out large-scale coronavirus antibody testing last week. The country launched three studies - o ne analysing blood donations, one involving the country's worst-hit areas and a representative study of the broader population.
In the first, 15, samples will be taken every fortnight from blood donations. Preliminary results from these two projects are expected to be published in May. In the third study, 15, people in regions across Germany will be tested for antibodies.
The research will begin next month. Swiss pharmaceutical giant Roche announced it would be launching a 'highly specific' antibody test by early May. The test will launch in countries that accept the CE mark, a global standard. Severin Schwan, the company's chief executive, told the Financial Times the company 'could easily get into the hundreds of millions' in the following months.
Mr Schwan said the test was 'highly specific' but refused to elabroate as trials continue on patients. Dr Simon Clarke, associate professor in Cellular Microbiology, University of Reading, said: 'This is a very interesting and potentially important advance in being able to diagnose who has been previously exposed to the coronavirus causing COVID, but I think the authorities in the UK would be wise to conduct independent evaluation, given how they've had their fingers burnt with other tests that they've purchased.
It remains unclear how quickly laboratories that do not already have that particular instrument would be able to obtain them and at what cost. Finland has also announced a similar - but much smaller - antibody testing programme. Finnish broadcaster Yle said the country will start testing random blood samples every week. It is analsying blood donations of Washington and New York City residents - two of the worst-hit regions in the States.
A separate survey is looking at random samples of people across the country, and a third is studying health workers. In Italy, Giancarlo Maria Liumbruno, the director-general of the Italian National Blood Center, is said to be trying to roll out antibody tests within weeks.
Mr Liumbruno said the country has more than 1. Mr Liumbruno said he plans to use the antibodies to treat coronavirus sufferers. Trials of this process have already started in some hospitals in Lombardy, Northern Italy - at the heart of the nation's outbreak.
Plasma from patients who recovered and tested negative for at least two weeks is used on those still battling COVID There is not enough information on antibody tests to know for certain how accurate they need to be.
Early studies appear to show they give very few false negatives meaning they rarely are wrong are determining if someone has never had the infection. But UK officials are worried by how often the devices give false positive results. Startling models from Imperial College London saw the Government change tack after scientists warned that up to , people could die without any action.
Experts have warned that dishing out coronavirus tests to be conducted unsupervised at home could lead to 'disastrous results'. Antibodies are not produced until between three and seven days after contracting the infection. This could result in a person thinking they are safe to go out in the community when they are not.
The manager said: 'However simple the test is, people will find ways of doing it wrong. The main issue is it's an antibody test — that's going to confuse people and cause problems. For this reason, England's Chief Medical Officer Chris Whitty has described them as 'dangerous', saying a bad antibody test was worse than none at all. But some scientists say that, even if the tests are just 50 per cent accurate, they at least give officials a clearer picture of who is infected.
The development of an antibody tests require some knowledge of the proteins that form the coat of the virus. Viruses are made up of many proteins, called antigens, of which some are shared with other viruses. Only a few may be unique to the particular virus. The proteins specific to the virus will trigger the production of antibodies that neutralise the virus, stopping it from replicating. Those sections of the viral protein coat must then be produced in the laboratory, using cell lines, to be tested in an immunoassay.
Scientists 'take that protein, put it in the bottom of a plastic well and put the blood serum in it and see if there's something that will stick to it,' said Dr Whittier.
Anna Petherick, a lecturer in public policy at University of Oxford, said immunoassays will form the basis of home testing kits for people who think they have had COVID
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