According to this paper the commercial LTF antigen tests seem to use N proteins from SARs CoV 2 as the marker but the antibody tests use the ACE/ACE2 as the marker. So a body swimming in vaccine related spike proteins should not effect the antigen test but for the antibody tests it definitely looks like a real problem.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8054491/
Thanks jmc. You were one of the people I had in mind when posing the question!
I will scour that report carefully. As you say, it seems to suggest that LFT tests use a different marker. It does not say that is always the case, rather that it is 'often' the case. Now 'often' needs to be referred to the net number of tests rather than, say, the various makes of test.
I had already found that the antibody test was a problem but that is not used to determine so-called 'cases'. The antigen test is what needs clarification.
This is the key quote from the paper for the first part of your question..
The most abundant N protein and antibodies against it are often the detection target in commercial tests to identify SARS-CoV-2 infected individuals, such as, Abbott’s BinaxNOW™ COVID-19 Ag Card[1] and Abbott’s SARS-CoV-2 IgG Architech[2].
And this is the best place to start for the second part of your question ..
In contrast, SARS-CoV-2 NAbs can be raised only against S protein. This is because SARS-CoV-2 virus invades its host via interaction of its S protein with ACE-2 protein on the surface of host cells [3,4]. All of the vaccines in the market or under development contain SARS-CoV-2 S protein or S protein-encoding gene. The capability of inducing long-lasting and high titer NAbs is one of the most important criteria in predicting the success of a SARS-CoV-2 vaccine.
There is a lot of discussion of the technicalities of this second quote in the paper. My guess is that if the spike protein does go into general circulation then any antibody LTE test based on ACE type markers is compromised.
The apparent increase in so-called 'cases' at the moment could be largely due to increased LFT testing on greater proportions of jabbed people.
It's a good question, I'll guess. A typical vaccine side effect (a slight fever) is generally a short lived event, it lasts 1 or two days. If it lasted longer there would be good grounds for vaccine hesitancy. While it is on going, the immune system is busy killing the cells that look suspcious, since the cells have no way to replicate, this is soon done. The amount of vaccine is titrated to ensure most people's bodies have disposed of the suspcious cells within a day or two. hence as long as the LFT is taken before or a long time after a jab, the problem you allude to should not happen. I imagine the sensitivity of the LFT is calibrated to minimise the possibility. Of course such calibration must be done properly or else the LFT would not find a real case.
Anyway, that's my guess.
complete garbage - why do you speculate on the mechanics of something you dont know the mechanics of?
In the UK at least you can get Anti-N and Anti-S antibody tests.
As far as LFDs go, the Innova which the UK mainly uses (the same one the CDC said to bin) uses the N protein so shouldn't trigger for/because of vaccination.
https://innovamedgroup.com/innova-rapid-antigen-test/
Abbott which they were evaluating is also nucleoplasmid. ( https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/890566/Evaluation_of_Abbott_SARS_CoV_2_IgG_PHE.pdf )
I refer people to this Twitter post:
https://mobile.twitter.com/holmenkollin/status/1415989536933490688
Something really odd is going on:
In Europe we are seeing surges at many places where most of the population has already been vaccinated.
At the same time, the 15 least vaccinated countries don‘t seem to face any problem.
At some point, denying this problem will get painful.
Could I have been right about the spike protein being used in the LFT tests, despite reports indicating otherwise?
This is definitely the go to place on antibody testing results
https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/bulletins/coronaviruscovid19infectionsurveyantibodyandvaccinationdatafortheuk/21july2021
Coronavirus (COVID-19) Infection Survey, antibody and vaccination data, UK: 21 July 2021
what is particularly worthy of note is that the 16-24 year old group had 40% antibody levels back in mid January 2021 before they were vaccinated
Figure 3: Percentage of adults testing positive for COVID-19 antibodies and percentage of adults who have been vaccinated by grouped age in England, Wales, Northern Ireland and Scotland
That should have been more than enough for herd immunity then for that group.
50% have t cell immunity, not all develop antibodies and antibody levels fall after exposure.
Numerous different studies in intensely infected areas had found that covid infections peaked at antibody levels of around 30% eg New York City , parts of Iran and Italy etc etc.
Figure 3: The highest percentage testing positive for COVID-19 antibodies was for those aged 80 years and over in England
Estimated percentage of people testing positive for antibodies to SARS-CoV-2 from a blood sample, by age, in the 28 days up to 11 February 2021, UK
what is particularly worthy of note is that the 16-24 year old group had 40% antibody levels back in mid January 2021 before they were vaccinated
Figure 3: Percentage of adults testing positive for COVID-19 antibodies and percentage of adults who have been vaccinated by grouped age in England, Wales, Northern Ireland and Scotland
That should have been more than enough for herd immunity then for that group.
Antibodies are not a single entity. Also antibody presence doesn't necessarily confer immunity.
Its very unlikely the UK will ever manage HI against Delta where the threshold is probably in the region of 85% *of the total population*.
what is particularly worthy of note is that the 16-24 year old group had 40% antibody levels back in mid January 2021 before they were vaccinated
Figure 3: Percentage of adults testing positive for COVID-19 antibodies and percentage of adults who have been vaccinated by grouped age in England, Wales, Northern Ireland and Scotland
That should have been more than enough for herd immunity then for that group.
Antibodies are not a single entity. Also antibody presence doesn't necessarily confer immunity.
Its very unlikely the UK will ever manage HI against Delta where the threshold is probably in the region of 85% *of the total population*.
Its only 85% is you put any credence in model derived inferred R0's from short time frame clinical cases numbers.
A quick search of the relevant literature will show multiple papers going into great detail explaining why those numbers are at best misleading and usually totally wrong for any public health use other than the control of single geographic cluster outbreaks. When the number can be used (with care) for monitoring the effectiveness of cluster outbreak control and remediation steps to get the outbreak under control. But for a pandemic. Useless.
And its only 85% if the R0 > 8 for community spread in the general population and you assume that the Susceptibility is 100%, zero immunity in the general population to the new variant. So unlike all other viral respiratory infections in the past. Which is quite simply ludicrous.
Based on current reliable clinical data the current most prevalent variety has a community spread epidemiology pretty much the same as all the other ones but with a much lower IFR and CFR. As expected. Because that is how variants work.
The only thing to be discovered now is just how often SARs CoV 2 throws up more virulent variants. Most like the same timescale as Influenza. Once or twice a decade. Although with HCOV's being far more mutagenic and the very bad history of HCOV vaccine candidates triggering new virulent variants who knows.
