In case anyone has bought, or used, or is even just thinking about buying, a home covid-19 antibodies test, the following article might be of interest.
What is not at all clear is how this applies in Wales, Scotland and Northern Ireland!
English retailers told to halt coronavirus home antibody test deliveries
Public Health England says labs must not process them until it has established their accuracy
They are using a German one in the US. Sorry no link !
These tests are virtually useless and may be harmful if you think you have a degree of immunity when you don't.
Blue Horizon state:
100% Sensitive at detecting IgG antibodies in people who have been ill from Covid-19 at 14 days or more after their first symptoms.
99.6% Specific. This means that there were only 0.4% of people that gave blood before SARS-CoV-2 or had a respiratory illness that was caused by another virus who tested positive for IgG antibodies (false positives)
This sounds good but we need to factor in the mathematics. Approximately 265,000 people have tested positive in the UK. Assuming a UK population of 65,000,000 a test that is 99.6% specific would give 260,000 false positives. Thus, if you test positive on one of these tests there may be a 50 / 50 chance you have had COVID-19! Fifty percent accuracy is not good enough to base decisions on. It's probable there are more than 265,000 who have been infected so my calculation probably exaggerates the problem.
I'm also suspicious of the comment about 'had a respiratory illness'. It's not clear if this 99.6% specific figure is based upon a ramdon selection of people who were tested (should be) or whether they selected people who had a respiratory illness. Selecting people who were symptomatic for COVID-19 would greatly increase the apparent accuracy of the test.
Once one looks at the figures in detail it becomes clear how difficult a task the government / NHS has in finding good tests.
Well, apparently in the Netherlands that found that stored blood from years before this virus was supposed to exist could test positive for antibodies. This suggests that a) the test cannot tell the different between antibodies for different coronaviruses (or apparently strep or hepatis) b) the alleged new virus isn't new c) the tests are not accurate. d) None of the above. But on the other hand, the tests for active infection can test positive on a goat, a piece of fruit and some motor oil and the NHS is quite happy to use those, so who knows? Perhaps home test interfere with their Stazi-style track and trace programme
Very concerning - as testing positive could mean the common cold anti-bodies. Another two weeks under house arrest whilst more plans are made to curtail our freedoms.
Of course DC has to stay - he's in the middle of some very important modelling in the dark wings - and will be organising the new order. Also the Global Vaccine Conference - GAVI - is taking place soon - virtually. - but hosted by UK.. Ferguson is Acting director of VIMC - Vaccine Impact Midelling Consortium.
If they do not have a full proof test - why is it starting today - the TAT - Track and Trace ??
Who do we trust ?
The NHS has resisted pressure to use antibody tests until they have found an accurate one. This has put enormous pressure on everyone involved but to their credit they have resisted. Vaccines have varying effectiveness, polio is fantastic whilst influenza vaccines save thousands of lives in spite of moderate effectiveness.
The cruical point is when infection rates are very low as in COVID-19 an antibody test needs to be 100% specific in order to avoid many false positives.
Will take a look ! Didn't know you could drive 265 miles in a Discovery without a refill .. 😎😕
Oh well that's sorted then !
If I remember that is what was reported. I guess it comes down to how many decimal places. There comes a point when the test is sufficiently accurate to be useful, my point is the over the counter tests are not.
Antibodies blood tests.
Hypo with negative antibody tests
Coeliac Home Fingerpick Test
What antibody test is this (NHS)?
Hashimotos antibodies tests
