Belgian biotech firm claims to have developed an antibody test that is 100% accurate - and is already making thousands of them per week (3 Pics)

A Belgian biotech firm claims it has developed a foolproof coronavirus antibody test that is 100 per cent accurate.

Liege-based ZenTech said it had started making tens of thousands of its  government-certified tests a week.

Zentech plans to roll them out in Belgium first before scaling up manufacturing to three million per month so the tests can be used in other European countries.

The devices detect if someone has previously had coronavirus and has since recovered, even if they are unaware they were infected. Results take 15 minutes. 

Scientists say they are crucial for countries coming out of lockdown because they can tell who is likely to have immunity to the virus. 

The announcement will raise hopes for antibody testing in the UK, where the Government has struggles to one reliable enough for mass-use.

Britain says it will not consider rolling out any antibody test that is less than 98 per cent accurate.

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. Zentech's test is not suitable for home-use. 

Belgian biotech firm ZenTech claims it has developed a foolproof coronavirus antibody test that is 100 per cent accurate

The company, based in Liege, said it had started making tens of thousands of its government-certified tests a week

Zentech plans to roll them out in Belgium first before scaling up manufacturing to three million per month so the tests can be used in other European countries

MailOnline has approached the Department of Health for comment. 

Zentech founder and CEO, Jean-Claude Havaux, said: '[The tests'] sensitivity is 100 per cent - meaning all patients who have COVID-19 antibodies, we see them with our test.

'We don't want, and don't intend for, these tests to be used by just anybody. It's not a pregnancy test. It's really pretty complicated to carry out and to interpret the results.'

He emphasised that the test kits were only for medical professionals, first in Belgium and then later in other countries in the EU and beyond.  

Antibody tests are seen as a crucial tool for determining who has had COVID-19 - especially non-symptomatic carriers - and could therefore be immune to it.

Such tests could pave the way to allowing people to return to work as countries mull easing widespread lockdown measures.

That could be especially important for healthcare workers on the front line of the  pandemic.

As a result, labs in several countries are racing to roll out huge numbers of reliable testing kits.

But the World Health Organization has warned that while reliable testing is welcome, the presence of COVID-19 antibodies is not proof that an individual is immune.

Even if there was immunity, it says, it is unknown how long it might last.

Dr Pascale Huynen, clinic head of the microbiology unit in Liege's university hospital - which confirmed ZenTech's test was reliable to 97 per cent - echoed the WHO.

'Nobody knows if the (COVID-19) antibodies are protective,' she said.

She added that scientists also do not know how long immunity could last, or whether the new coronavirus might mutate around any initial immunity, as happens with the flu. 

ZenTech's test, she said, simply indicates whether a patient has 'come into contact' with COVID-19 with a positive or negative result. It does not show the level of antibody response.

But that in itself is useful for determining the spread of the virus in a population, and for patients who have not received a nasal swab tests that detect whether a person is in the infectious phase, thought to last around two weeks. 

Pressure will now begin mounting on the UK Government to look into the tests. Minister promised weeks ago that antibody tests would be rolled out en-masse.

Britons were told they would be able to buy them from Amazon or Boots. 

But none have so far proved to be reliable enough for the public.   

The Medicines and Healthcare products Regulatory Agency says no test under 98 per cent accurate is safe for mass-use. 

However some scientists say that even imperfect tests which lack sensitivity can be used to estimate the true scale of infection.

Eleanor Riley, professor of Immunology at the University of Edinburgh, told The Guardian: 'Antibody tests – even if they lack some sensitivity – can be used to estimate what proportion of the population has already been exposed to the virus. 

'This is really helpful in telling us whether there is likely to be widespread immunity in the population and thus how likely there is to be a second wave of infections (and how big that wave might be), once the social-distancing measures are relaxed.'

There have only been 4,800 antibody tests carried out on COVID-19 patients in the UK. They are being trialled at the Defence Science and Technology Laboratory at Porton Down, near Salisbury. 

By comparison, Germany is trialling the tests on tens of thousands of its population.

Last month, the UK Government ordered 3.5 million finger prick tests, mainly from Chinese manufacturers.

Later it announced it had placed provisional orders for 17.5 million tests from nine firms including some based in the UK.

Among them were two tests made by Chinese companies. Britain paid an estimated £16 million for them. 

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 to now be looking for 'home grown' devices made by British firms. 

But UK-based manufacturers are struggling to access blood samples of infected patients to trial their devices on. Essex-based Biosure said there was 'a national shortage' of samples.

It is now calling for blood donations from members of the public who were either diagnosed with, or were suspected of having, the virus.

A spokesperson told MailOnline: 'We have discovered there is no current UK based bio-bank for confirmed positive COVID-19 blood samples.

'We recognise the Government is under immense pressure with this global crisis, so for swift action we need to call to the nation for urgent support.

'We are asking people to fill in an on-line questionnaire so we can build a database of people who have been diagnosed with COVID-19 and who would, if needed, be prepared to provide a small sample of their blood. 

'People who fit the criteria will be contacted and sent a collection kit though the post, so that a blood sample could be self-collected at home and posted back for inclusion in our validations.' 

DIY HOME ANTIBODY TESTS CAN'T BE RELIED ON, OXFORD UNIVERSITY STUDY FINDS

Rapid coronavirus antibody home tests cannot be relied on to provide reliable results, an Oxford University study suggests. 

But researchers said laboratory tests showed promising results when indicating whether someone had developed COVID-19-specific antibodies. 

They found home antibody tests were accurate between 55 to 70 per cent of the time. 

Antibody tests analysed in a lab were correct 93 to 100 per cent of the time.

PCR tests - which the Government is currently using - gave the correct result 95 to 100 per cent of the time. 

The authors write that there is an urgent need for robust antibody detection approaches to support diagnostics, vaccine development, safe individual release from quarantine and population lockdown exit strategies. 

However, the early promise of the fingerprick-type home tests has been questioned following concerns about sensitivity and specificity. 

The research indicates DIY commercial antibody tests for home-use are not sensitive enough.  

The investigations were led by the National Covid Testing Scientific Advisory Panel. 

Professor Derrick Crook, of the Nuffield Department of Medicine and NIHR Oxford Biomedical Research Centre, University of Oxford, is the corresponding author of the study that has not been peer-reviewed. 

The researchers write: 'The performance of current LFIA devices is inadequate for most individual patient applications. 

'ELISA can be calibrated to be specific for detecting and quantifying SARSCoV-2 IgM and IgG and is highly sensitive for IgG from 10 days following symptoms onset.' 

The antibody IgM and IgG are the different antibodies the immune system produces - when it is attacked - depending on the stage of infection. 

In their pre-print study, the researchers tested samples from 40 people. The ELISA test detected both Covid-19 antibodies in 34 of the 40 patients, with the diagnosis confirmed with a separate test. 

IgG levels were detected in 31 out of 31 patients tested 10 or more days after symptom onset. 

Commenting on the findings, Eleanor Riley, professor of immunology and infectious disease at the University of Edinburgh, said: 'It shows that the problem with the commercial rapid antibody tests is that they are not sensitive enough - they fail to pick up antibodies in over a third of people who do in fact have antibodies. 

'However, these tests do have acceptable levels of specificity - that is, they are only picking up people who have genuinely been exposed to the Covid-19 virus. 

'This means if your test is positive, you can be confident that you have been infected and have antibodies. 

'But if your test is negative, you can't rule out that you might have been infected. '

Just as importantly, this paper shows that we do have a very good assay for use in the lab.' 

The authors summarise: 'Antibody testing is crucial to inform release from lockdown.'