The government has doubled down on its policy that positive Covid cases identified by tests in school don’t need a follow-up lab test to confirm the result, insisting that pupils must still self-isolate even if the more reliable test contradicts the original outcome.
In an email to leaders today, seen by Schools Week, the Department for Education insisted that a negative polymerase chain reaction (PCR) test cannot override a positive result from a rapid-result lateral flow device (LFD) test taken by pupils in school.
As confirmed by the government yesterday, the opposite is the case for LFD tests taken by pupils at home. Downing Street clarified that pupils who received a positive result from an at-home test could return to the classroom if a subsequent PCR test comes back negative.
The different policies for tests taken at home and in school have led to confusion, but DfE explained today that it was taking the approach because tests conducted under supervision in school were less likely to be incorrect.
In its email to schools, the DfE said: “PCR testing is not advised if you have received a positive result from an LFD test at a school or college test site.
“If a parent was to do this and it returned a negative result, the policy remains that the pupil or student, their close contacts, and other members of their household must still self-isolate.”
Secondary school pupils are expected to be tested three times on-site in the first fortnight back at school, switching to twice-weekly home testing after that.
LFDs are being used both for in-school and at-home testing due to the speed in which they produce a result.
PCR tests are recognised as the “most reliable Covid-19 tests” by the government, but as they are processed in a laboratory it takes much longer to receive their results.
A blog released by the DfE today explains the difference in the rules is because when “a pupil’s test has been taken on site under supervision, the chance of it being incorrect is minimal so there is no need for a further test to confirm the result.”
The blog goes on to say that if taken correctly, “there is a very small chance of a home test being wrong but there is a slightly higher chance of it being administered incorrectly”.
Therefore pupils who receive a positive test in these circumstances should report the result and arrange a PCR test.
“In the event that the PCR test is negative – that they do not have Covid 19 – this overrides the lateral flow test if it was taken at home and they should therefore return to school”, the DfE added.
Fears over false-positive Covid results at school
Last week biostatistician professor Jon Deeks, of the Institute of Applied Health Research at the University of Birmingham, warned false-positives could mean pupils and staff having to self-isolate unnecessarily and miss more valuable learning time.
The DfE blog states that “robust evaluations” from Public Health England and the University of Oxford show LFDs have “extremely low rates of false positives”.
The Department of Health and Social Care (DHSC) says the Innova SARA-CoV-2 Antigen Rapid Test used in schools has a false-positive rate of 0.32 per cent.
NHS Test and Trace statistics show that just 0.19 per cent of all lateral flow tests (LFTs) results for pupils reported by secondary schools so far this term have been positive. The figure is 0.13 per cent among staff.
But Deeks warned: “The issue when you’re not detecting many cases is you have to think very carefully ‘are you detecting more than we would get false-positives?’”
The problem from the start with the lateral flow test was false negatives rather than false positives. This fact has been hidden lately but is far more dangerous than the odd false positive.
Yes i noticed this fact was completely missed in this article. It’s extremely relevant as you get the hidden covid 19 spreaders with the false LFD result. An absolute time bomb in a school setting.
As far as the spread of covid goes of course false negatives are more of a concern . However my understanding is that the higher the viral load the less chance of a false negative. False positives are a concern though to parents of teenage children who have watched the mental health of youngsters shattered during this last year . If the statistics are correct , with appropriate 3.5 million pupils in secondary schools and a false positive rate of 0.3 , then we are talking about 18,000 false positives weekly . Most secondary school bubbles are between 60 and 200 pupils , so let’s say that’s an average of 100 airing on caution . That’s 180,000 children being sent home to isolate for no reason every week . I personally think that’s an area for concern too . Yet again youngsters paying the price whilst those vaccinated are now breaking the rules. . At what point will the teenagers be able to live without fear and testing ? Is it when every adult has been vaccinated? will they still be in this cycle in June when the country opens up . When will they be offered the vaccine themselves ?
After some investigation and looking on the Innova website (makers of the Lateral Flow Tests), they confirm that the sensitivity of picking up a positive case is only 48. 89%. High risk of false positives and false negatives.
https://innovamedgroup.com/antigen_testing/
A colleague has contacted them due to concerns of what is on the test swabs and it is sterilised with Ethelyne Oxide. This is very toxic when inhaled in the nose or throat, has DNA altering properties and has cancer causing ability. The most noted cancers caused by EO is Lymphoma & Leukemia. Stomach and breast cancer has also been reported.
https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/ethylene-oxide
So sticking those swabs up your nose or down your throat is dodgy. The benefit of that does not out weigh any potential risks. But that is just my opinion. Just wanted to share the info. I suspect they will use the same on PCR Tests to sterilise them.
The swabs you are making children put up their noses are sterilised using Ethylene Oxide. Lymphoma & Leukaemia are the most common cancers caused by Ethylene Oxide exposure. Have a look at the national cancer institute if you are in any doubt about this. This is ritual child abuse and I am disgusted at all of you who are standing by and allowing this to happen. If you have any humanity, raise this with your local head teacher