Authorities confuse after calling on companies to end Covid-19 antibody testing

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British officials aroused anger and confusion today with a sudden decision to prevent private companies from testing Covid-19 anti-bite antibodies for the public.

The Medicines and Health Products Regulatory Agency (MHRA) has told companies offering to test blood samples that people are removing fingerprints to “temporarily stop providing this service.”

Until then, people had been able to buy mail-order kits for more than £ 69 from online pharmacies to find out if they had ever had the coronavirus.

The tests have been around for weeks online, with Superdrug even having to suspend testing due to overwhelming demand.

They involve taking blood and looking for signs of past infection, which is indicated by the presence of antibodies from the immune system.

But the government is said to have become nervous about people discovering that they could be immune to the virus and ignoring the lock rules.

The move, which authorities say is a ban and is just a hint, has led critics to accuse the government of “reconciling as it goes”. A top scientist said it showed “lack of foresight.”

MHRA officials met this morning to discuss the matter and are reviewing the tests involved.

It only applies to tests that rely on people taking their own blood from the finger, not samples using professional venous blood.

It is not yet known how many of them have already been sold, but it is understood that this affects thousands of people. Superdrug only admitted to having received a “high demand”.

The problem has just been brought to light because officials have noticed that an increasing number of these home tests have been offered in the past few days, MailOnline understands.

Abbott, one of the makers of a government-validated test that is used by Superdrug, is furious that his tests are being used with self-sampled blood, which was not the intended use. He has already sold 800,000 tests to the NHS.

The MHRA’s message has been confusing because companies have purchased the same government-approved tests – which will be used on the NHS and social workers starting this week – but are using them in a different way, which makes it less precise.

It is not believed to be linked to a report released yesterday by the United States Centers for Disease Control & Prevention, which suggests that even very accurate antibody tests can be wrong up to 50% of the time when they are used for a rare virus.

Antibody tests use blood samples to look for signs of past infection and, if positive, show that someone may have some degree of immunity to a disease. However, scientists still don't fully understand how much immunity people develop against Covid-19, if any.

Antibody tests use blood samples to look for signs of past infection and, if positive, show that someone may have some degree of immunity to a disease. However, scientists still don’t fully understand how much immunity people develop against Covid-19, if any.

Cellular microbiology expert Dr. Simon Clarke at the University of Reading said making the decision so late in the day was “really strange”.

At least half a dozen companies have already purchased antibody tests and are selling them en masse to members of the public, many of whom can no longer get results despite payment for a private service.

Dr. Clarke said the government is likely panicking that people who test positive for antibodies may believe they are immune to Covid-19 and be brave enough to break the lock rules.

He told MailOnline, “It’s really strange. At least one of the government-validated tests is commercially available.

“Why they tell people not to use them; they don’t want people to assume they’ve had the virus and are immune.

BRITAIN’S COVID-19 TESTING SHAMBLES: A TIMELINE

12th of March: Professor Chris Whitty has announced that large-scale public coronavirus testing will end. The epidemic was too large, authorities have since admitted, and only hospital patients were able to be tested within the limits of their capabilities.

March 19: Boris Johnson has promised that “as simple as a pregnancy test” antibody test will be available for people to use at home – it’s still not a reality at all.

March 25: Sharon Peacock of Public Health England said the UK had bought 3.5 million antibody tests and was evaluating them to make them available “in a few days” – they were all deemed unnecessary and no have never been made available to the public.

April 2: Health Secretary Matt Hancock has an ambitious goal of 100,000 coronavirus tests every day by the end of the month. On April 1, the government made 10,412.

April 3: Universities and private labs caused an uproar over the “small vessel” fiasco when they revealed that the government had declined offers of help for swab testing to find out who had the disease. time.

April 16: The New York Times reported that Britain had spent £ 16.5 million on antibody tests it no longer wanted to use.

May 1: Health Secretary Matt Hancock said the government had reached its goal of 100,000 tests per day, but it turned out that it had just sent 39,000 that day and that many may never have been returned or analyzed.

“They don’t want to think that this is probably right … but it should have been put to bed earlier.”

He said the decision-making now shows “a lack of foresight that an error could cause problems”.

It is known that at least two laboratories stopped treatment following the “directives” of the MHRA.

Professor Karol Sikora, a former cancer chief at the World Health Organization, has taken the antibody test from the Rutherford cancer centers where he is medical director.

He told this website: “In Britain, the tests are appalling. There doesn’t seem to be a strategy and it changes from day to day. They reconcile progressively …

“It is another failure. We should not have reached this point in the pandemic and not have had a properly developed testing strategy for the virus and the antibodies. It should have been settled at the start.

“The real problem is that if you have this in the post and you’ve never done it before, the chances of you screwing it up are high – it’s just the way these things are designed. And people are nervous about pricking their fingers anyway. So there’s a lot of inconsistency. “

The finger prick tests have never been approved by the government because they use a different type of blood than the one on which the official tests were validated.

In the laboratory, tests use blood drawn directly from a patient’s veins, while home tests can use blood from capillaries, which are tiny vessels that carry oxygenated blood through the skin.

After noticing an increasing number of pharmacies offering bite tests at home, the MHRA is now cracking down on these companies by urging them to stop.

The tests remain legal, and it is unclear whether the government has legal powers to prevent companies from taking the tests anyway, but officials fear the results will not be reliable.

People who bought the tests complained on Twitter that companies shouldn’t have sold them in the first place if they weren’t approved.

One user, Maneesh Juneja, tweeted: “I wonder if consumers like me who paid £ 69 for a covid-19 antibody test where they’ve already gotten a result, will reimburse consumers now that the tests with the method need to be validated by the MHRA?

Another, Helen Ashby, said that she ordered a test and tweeted at Thriva online pharmacy: “I really shouldn’t have taken my order then!

Ben Read said, “Stop selling anti-coronavirus antibody kits until you are authorized to sell them. I got the run for a test I bought last week, supposedly blocked by MHRA advice in April. Pretty deceptive. ‘

People who bought tests showed on Twitter that they were not happy that they had sold something that was not approved by the government

People who bought tests showed on Twitter that they were not happy that they had sold something that was not approved by the government

The Medicines and Health Products Regulatory Agency (MHRA) told MailOnline last night, “Patient safety and public health are our top priorities and it is in everyone’s interest that antibody testing are as reliable and meaningful as possible.

CDC WARNS ANTIBODY TESTS ARE FALSE UNTIL HALF OF THE TIME

Antibody tests for Covid-19 may be wrong up to half the time, according to updated information from the Centers for Disease Control.

The CDC now warns that antibody tests are not precise enough to be used for any political decision, because even with high specificity, “less than half of positive tests will really have antibodies.”

He urged caution with the test results, as many false positives could lead people to believe that they are immune to coronaviruses and to act accordingly.

Health care providers may need to test patients at least twice to give a more accurate reading, adds the new guide published on the CDC website.

Antibody studies, also known as seroprevalence research, are considered essential to understanding where an epidemic spreads and can help guide decisions about what restrictions are needed to contain it.

There is currently a high level of inaccuracy in testing, however, due to the rarity of the virus in the population.

If the infection has affected only a small number of people tested, it will have an amplified margin of error, explains the CDC.

This means that even a test with an accuracy of more than 90% can still miss half of the cases if only 5% of the population has been infected.

“There are several test service providers in the UK that offer Covid-19 antibody tests using a capillary blood sample taken from a small container.

“We are asking all providers of Covid-19 antibody test services in the laboratory using capillary blood taken from a finger prick to temporarily stop providing this service until home collection of this type of sample has been properly validated for use with these laboratory tests.

“The use of non-validated sample types can lead to unreliable results and, as such, we work closely with service providers, laboratories and test manufacturers to resolve regulatory and regulatory issues. patient safety.

“People who have purchased one of these sample kits and received an antibody test result should not consider the result as reliable and should not take any action on it.

“It does not affect rapid point-of-care tests or laboratory tests using venous blood.”

The way antibody tests work is that a blood sample is taken from a patient, either by a healthcare professional or by themselves, and displayed in a laboratory.

There, qualified technicians test the blood for antibodies to the coronavirus, which are substances in the immune system created when a person is infected with the virus.

People then receive a result in which the presence of antibodies – a positive result – indicates that they have already had the virus, or the absence that they do not have it.

The laboratory analysis phase is now blocked by the MHRA because the tests are used with blood taken by the patient himself.

The best-known company providing antibody tests, Superdrug, voluntarily stopped publishing its tests last week due to huge demand, so that it could get through all of the samples ordered.

She did not confirm whether the MHRA rule had affected her service.

HOW CAN ACCURATE TESTS BE INACCURATE?

Antibody tests with what could be considered a high level of accuracy can still produce large margins of error if only a small proportion of a population has been infected.

A specific 95% test, for example, will always produce five false positive results from a group of 100 people.

Even if it is sensitive enough to detect everyone who has had the disease, it will still return five false positives, and the effect this has on the results of a survey can be significant if the number of true positives is low.

If the prevalence of antibodies is low – for example, only 5% of people in the group have had the disease – the results could end up being half wrong. The 95% test in this situation should give 10 positive results – five good, five false.

This means that the functional accuracy of the test, known as its true predictive value, is only around 50%.

The effect of these false positives is amplified if the prevalence of the virus in the population is low and less noticeable if the prevalence is high.

For example, if 30% of the population was infected, these five false positive results would be offset by 30 true positives, making the test more accurate at 85%.

A more specific test can reduce this effect; by comparison, a specific test at 99.9% would give the wrong result per thousand – 100 per million.

A spokesperson said, “We have been contacted by the MHRA and are currently discussing with them the laboratory testing services for Covid-19 and the updated guidelines provided by Abbott.

“We are also contacting all of our Covid-19 antibody test customers today to provide further information on the quality and safety of our Covid-19 antibody test service. We update them on our current location and invite them to contact us directly if they require further information or have any questions or concerns.

Lloyds’s pharmacy was also affected by the decision, but did not confirm it.

Andy Sloman, the company’s managing director, said, “We are working closely with our partners and regulators and have made the decision to temporarily suspend the LloydsPharmacy Online Doctor COVID-19 antibody test service pending further guidance.

“The health and safety of customers is our top priority, especially in such a difficult and uncertain time.

“We are closely following the advice and guidance in development on COVID-19 antibody testing from government and healthcare professionals.”

Professor Ian Jones, a virologist at the University of Reading, said: “In general, I am in favor of freedom of choice as long as there is complete information about the reliability of the test performed.

“After all, you can buy any number of totally useless products sold under the vitamin or” immune health “banner and the government does nothing.

“It should be noted that part of Germany’s success in fighting the epidemic is due to a campaign of commercial tests, in this case for active infections.

“The problem with centralization is that it cannot handle the numbers and that any teething problem affects all the samples.

“A broadcast system avoids at least that. It seems to me that the problem is the lack of specific information on acceptable kits and the providers who offer them. Then people can choose.

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