Lateral flow Covid tests are being given to millions of schoolchildren with the WRONG instructions that they are for anyone with symptoms
- Chinese-made kits had leaflets saying they were for those with Covid symptoms
- But official guidance states they are only for those without warning signs
- Britain’s medical regulator says it is investigating following the revelation
Controversial lateral flow tests may have been sent out to millions of schoolchildren with the wrong instructions, it has emerged.
Many of the Chinese-made kits contained guidance saying they were to be used by people suffering symptoms of coronavirus – going against official UK guidance.
The devices were also sent out with a notice that they were to be administered to people ‘suspected of Covid-19 by their healthcare provider’, The Telegraph reports.
It comes despite the Government claiming the main purpose of the 30-minute tests is to catch asymptomatic carriers, who make up a third of all new infections.
Britons who fall ill are supposed to get a PCR test, which are done in a laboratory and are much more accurate, and self-isolate straight away. This process automatically logs the case in the Government’s contact tracing programme.
Experts warned the oversight could lead to patients not reporting their results or being tracked down by Test and Trace – risking spreading the disease further.
About 3million lateral flows are being deployed every week, mostly in schools where children and staff are required to be tested twice weekly.
Britain’s medical watchdog, the Medicines and Healthcare products Regulatory Agency (MHRA), has confirmed it is investigating the issue.
The Government has been criticised for rolling the lateral flow devices out for people to do themselves, despite manufacturers admitting they are built for professional use.
Numerous studies have shown the kits are far less accurate when self-administered and leaked Department of Health emails last week revealed senior officials fear they only pick up on 10 per cent of infections when done this way.
The tests have been mired in controversy since they were put into mass use when schools in England reopened last month. They are now available for free to all adults with no Covid symptoms.
Many lateral flow test kits were handed out with this advice marked as v.1.1.4, 24 November 2020, stating the swabs could be used for symptomatic and asymptomatic people
But others contain second advice saying those with symptoms should refer to the NHS website. Official guidance says those with symptoms should get a PCR test
Lateral flow devices were designed as the rapid alternative to PCRs, taking 30 minutes to give results compared to at least 24 hours with the initial tests. But scientists have raised concerns over how sensitive they are
PCR AND LATERAL FLOW TESTS: THE KEY DIFFERENCES
A PCR test can cost upwards of £180 per person, with the swab needing to be processed in a lab.
The UK, on the other hand, favours faster tests which are not lab based and give a result within 15 minutes.
These rapid coronavirus tests, known as lateral flow tests, are ones that can be done on the spot using portable equipment.
They are faster and cheaper than lab-based PCR tests, which the government uses to diagnose people, but are less accurate.
Some schools have given pupils tests with out-of-date leaflets marked as ‘Version 1.1.4, 24 November 2020’.
They state: ‘You can use this self-test kit if you have symptoms or if you are asymptomatic (you do not have symptoms).’
But guidance issued in a separate version marked as version 1.3.2, 15 January 2021 signposts those with symptoms to the NHS website.
Online, the NHS says lateral flow tests are only for people ‘without coronavirus symptoms’.
A scientist whose children were handed the out-of-date tests told The Telegraph the packages were ‘deeply confusing’.
‘If symptomatic people use lateral flow instead and fail to report their result, then we’ll lose control and it won’t give contact tracers a chance,’ they said.
Experts have already raised concerns over the sensitivity of these tests in asymptomatic cases.
But Government officials insist the benefits of testing people without Covid symptoms – weeding out silent carriers of the virus – far outweigh their pitfalls.
A Cochrane Review found the kits fell short of the World Health Organization standard that every Covid test must pick up at least 80 per cent of infected people.
Covid infections were spotted 72 per cent of the time in symptomatic cases on average, but this dropped to 58 per cent among asymptomatic individuals.
And Public Health England data shows one in ten positive results were false in March, meaning the tests wrongly triggered people to self-isolate after suggesting they were infected with the virus.
PHE found 3,248 positive results were found to be inaccurate after they were followed up by more reliable PCR checks.
One outspoken critic of the self-testing policy, Professor Jon Deeks, said last week that tens or hundreds of people could be affected by one person getting a false positive result.
He added: ‘If you get a positive result it is essential that it is confirmed by a PCR test as soon as possible to check that you and your contacts do not isolate unnecessarily.’
The UK Government has spent billions of taxpayers money securing the tests, despite concerns over how well they work.
The Medicines and Healthcare products Regulatory Agency (MHRA) said: ‘I can confirm that we are looking into this.’
Ministers hope the multi-billion-pound swabbing blitz – which involves Boots and other local pharmacies – will help life revert back to normal.
But scientists have warned the scheme could result in a ‘public health disaster’, with thousands forced needlessly to self-isolate and others given false confidence that they are safe.
One of the biggest issues is that the tests have low sensitivity, meaning they do not pick up everyone who is carrying the virus.
People who have the virus but still test negative – false negatives – might get misplaced confidence from the test result and be less strict about following lockdown rules that someone who hasn’t been tested, experts say.
This could lead to them going back out into the community and spreading the virus without knowing.
But government experts are satisfied the DIY swabs, widely used by schools, care homes and the NHS, are a key tool in reopening society.
The tests are said to already have identified 120,000 cases that might not otherwise have been picked up.
HOW LATERAL FLOW TESTS ARE ONLY TRUSTWORTHY WHEN ADMINISTERED BY TRAINED STAFF
Lateral flow tests are only accurate at diagnosing coronavirus when administered by trained professionals, studies have repeatedly shown.
The tests, which give results in as little as 15 minutes, use swabs of the nose or throat. Samples are then mixed in a testing liquid and put into a plastic cassette which can detect the presence or absence of coronavirus and then produce an image of a line, the same way as a pregnancy test, to indicate whether it is positive or negative.
The Department of Health and NHS are instructing people to use the tests on themselves, despite manufacturers of some kits saying they shouldn’t be used as DIY swabs.
Both the swabbing procedure and the use of the test cassette can easily be done wrong and affect the accuracy of the test.
If the swab isn’t done for long enough, or deep enough into the nose or throat, it may not pick up fragments of virus. Medical professionals are also able to use nasopharyngeal swabs, which go right to the back of the nostril, whereas this is not advised for people who test themselves.
And if the sample isn’t properly inserted into the cassette the result might be wrong, or people may misread the display when it produces a result.
SELF-TESTING CUT ACCURACY FROM 79% TO 58%
A University of Oxford and Public Health England evaluation of the Innova lateral flow test, which is being widely used in the UK, found its sensitivity – the proportion of positive cases it detected – fell from 79 per cent to 58 per cent when it was used by untrained members of the public instead of lab experts.
Based on this evaluation, officials pushed ahead and used it for a real-world self-testing trial.
PILOT IN LIVERPOOL FOUND FEWER THAN HALF OF POSITIVES
When the same Innova test was trialled on members of the public in Liverpool – with people taking their own swabs and trained military staff operating the tests – the swabs picked up just 41 per cent of positive cases.
In the study the rapid tests detected 891 positive results, compared to lab-based PCR swabs that found 2,829 positives in the same group. This means 1,938 people got a wrong negative result from the rapid test.
The study didn’t compare this to professionally done rapid tests, but the manufacturer Innova claims its test is 95 per cent sensitive in lab conditions.
…BUT TESTING DONE BY MEDICS IN SLOVAKIA ‘REDUCED INFECTIONS’
Despite rapid lateral flow tests getting bad press, officials in Slovakia used them on 5.2million people – almost the entire population of 5.5m – in a trial that a study later estimated to have cut the country’s infection rate by 60 per cent.
The tests used were between 70 and 90 per cent accurate and all the swabs and evaluations were carried out by trained medical workers. They used deep nasopharyngeal swabs, that go to the back of the nose, whereas self-testing generally relies on a swab of only the nostril.
London School of Hygiene & Tropical Medicine researchers said that the scheme successfully weeded out coronavirus cases that wouldn’t have been found otherwise, slashing the number of cases by over half in a week during a lockdown.
HOW RAPID TESTS ARE DIFFERENT TO LAB-BASED PCR SWABS
Lateral flow tests are an alternative to the gold standard PCR test – known scientifically as polymerase chain reaction testing – which is more expensive and more labour-intensive but more accurate.
PCR tests also use a swab but this is then processed using high-tech laboratory equipment to analyse the genetic sequence of the sample to see if any of it matches the genes of coronavirus.
This is a much more long-winded and expensive process, involving multiple types of trained staff, and the analysis process can take hours, with the whole process from swab to someone receiving their result taking days.
It is significantly more accurate, however. In ideal conditions the tests are almost 100 per cent accurate at spotting the virus, although this may be more like 70 per cent in the real world.
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