Some findings are coming out re antibody testing. Apparently significant numbers who test positive on PCR, do not develop detectable antibodies after recovery. Commentary is that they recover by innate immune response alone. edit. or recover by B cells which do not produce antibodies…
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This was said very early on, and would make this a very clever virus if true.
I would have to read the original reports to be convinced the PCR+ results were not false positives. Also it’s more likely they recovered via CTLs (“killer T cells”) which are an independent arm of the immune system to antibodies and much more effective than innate immunity.
I saw a calculation that the USA had many more infections than cases, based on the number of people at large with antibodies based on seroprevalence testing. So the actual number of those infected is more than 20M.
If there are a significant proportion of recovered patients who do not have antibodies, it increases the actual number of infections significantly, maybe 25M or beyond.
In any case CDC significantly say this, which might be an issue with a lot of vaccines in development.
We do not know whether having SARS-CoV-2 antibodies provides protection against getting infected again. Other studies are planned to learn more about SARS-COV-2 antibodies, including how long they last, whether or not they provide protection against getting infected again, and if you get infected again, whether or not they can make that illness milder
See the update of 25/6/2020, Commercial Laboratory Seroprevalence Survey Data
Since we have some pesky clusters sending Victoria into serious loss of pride, subject to justifiable discriminatory actions by other states, and annoyance at the people who refuse to be tested, here is an analysis of many clusters worldwide. This sort of info probably helps guide the medical officers in what is safe to open and what is not, and what restrictions need to be applied, There is a google spreadsheet in there that’s very interesting. The rest of the article consists mainly of background and disclaimers.
EFA
Moderna mRNA phase 1 study.
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A new peer reviewed Nature paper reveals some very exciting findings for the long term.
Essentially it is this:
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Subjects who were exposed to SARS-COV (2003) and developed antibodies back then, still develop antibodies to SARS-COV (2003) when challenged. So the memory T cells hang around for 17 years.
Since SARS-COV-19 is very similar to SARS-COV (2003) immunity may last for 17 years or more after infection and/or immunisation with a successful vaccine. It is also indicative of likelihood of herd immunity developing. ( subject to virus mutation rate) -
Those with SARS-COV (2003) antibodies, show a reaction to SARS-COV-19 and demonstrate a level of immunity. There are not many people infected by SARS-COV.
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Some people already have immunity to SARS-COV-19 never having been in contact with SARS-COV (2003)
Maybe the animal Beta coronavirus ( effects the GI tract) found in cows, dogs, bats and ferrets which is not dangerous to humans stimulates an immune response in humans which produces antibodies that also attack SARS-COV-19
How some humans come into contact with the Beta coronavirus is not known at this point.
Dogs seems most likely, but what proportion of dogs have been exposed to the virus?
Many questions arise.
Nature Article
https://www.nature.com/articles/s41586-020-2550-z_reference.pdf
Lay man’s you tube explanation:
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Some say vitamin D deficiency in some groups is strongly linked to immune response, others are looking at genetic predisposition.
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Stage 4 shut down list
So most people would have heard the news of the Pfizer vaccine being “90% effective”
In the absence of any real details in the media reports, what does this mean?
Pfizer’s Phase 3 trial involved over 40,000 participants. Half were given the vaccine, the other half a placebo. Nobody was intentionally infected: everyone just went about their normal lives facing the “normal” risk of exposure, which in the US we know is much higher than just about anywhere else.
The whole group was monitored for Covid infections, of which there were reportedly 94 confirmed cases. The number of cases in each group has not been released yet, but we can assume that the number of cases on the placebo group must be significantly higher than those in the vaccinated group. Anything better than a 60:34 split in the control v vaccinated groups would be “significant”. To get “90% efficacy” the split would be greater than this i.e. many more in the control and less in the vaccinated.
Another possibility is that 90% have made antibodies to the vaccine. While these antibodies will probably be protective, we do not yet know if the presence of antibodies is a solid guarantee that 90% of vaccinated people will not be infected, nor is it a guarantee that the antibody levels will remain protective over years.
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My understanding it is only 90% effective after two doses - not sure how far apart they would be.
Yes. For this type of vaccine, two doses are needed to get antibodies of the IgG class- usually doses are given 2 weeks apart.
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I guess its easy to say in hindsight that the whole world needed to stop the virus back in March 2020.
Now the whole world is a petri dish for SARS-COV-2. The more widespread it is and the more the virus spreads the more likely even at its comparatively low rate of mutation, that a mutation will arise that is more infectious. Thats pure deduction from Darwin. So, it took about 12 months for the mutation to arise but now it has. It is stonking the UK and will surely become the dominant strain going forward and thus the strain which will evolve from this point.
The worry now is that a more lethal form may evolve, and/or one that effects younger people. If the high infectiousness persists, and the infectiousness prior to symptoms persists, we are in big trouble.
Hopefully the introduction of the vaccines will enable us to stop it in its tracks, reduce its prevalence in the community and reduce its likelihood of evolving further in a nasty way.
Is there a definitive answer on whether or not people can be infected a second or third time?
Or are people “shedding dead virus” some time after the first illness?
If we really think about the creation of the vaccines on the run - normally it takes years to create a workable vaccine which in this day and age with covid19 it would need constant tweaking.
At the rate covid19 can mutate and change itself. I cannot see how any current vaccines will stop it maybe slow it but not stop it. We humans need to remember, viruses and bacteria have been on this planet longer than any living thing. They both have an innate intelligence or a consciousness and can change themselves to suit the circumstances and the proximity. I think that’s something that is difficult for most people to understand.
Humans might be better off coming to an understanding instead of coming from the perspective, we are smarter than everything else on the planet therefore, better and smarter and can control everything. Sadly, we are being shown that’s not how it works.
There are NO quick fixes.
Actually every year they modify the flu vaccine some times several times as new strains appear , so it is possible to adapt quickly for some viruses
It was said early in the COVID epidemic that its rate of mutation was not like influenza, so the need for a new vaccine each year is not expected. But yes, we will just have to come to terms with this as another pathogen that older people need to deal with and it will be around for a long time I think.
My doctor suggested I am vaccinated for Flu, Shingles, and Pneumococcal and its a good idea. As a person ages their immune system weakens. Older folk need a little help. Vitamin D supplement helps if you are an indoor person.
As I saw explained by someone better qualified than myself, the US vaccines create antibodies that target the spike protein. The clever thing about that is that if any other part of the virus mutates, the vaccine will still be effective. If the virus mutates the spike protein, rendering the vaccine less effective, then it has also just reduced its own ability to be infectious.
The vaccines were created from the original virus strain/s, yet all the mutations so far seem to be no less vulnerable to antibodies produced from the vaccines, and given the huge numbers of people infected over the last year, if vaccines are spread worldwide and number of infections reduce, then the opportunities for new strains will also be reduced, as they have to infect a person and incorporate some of that person’s DNA in order to have an opportunity to mutate. Less people being infected also equals less mutations.
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CVT is a big issue re vaccine hesitancy. A preprint paper recently attempted to clarify this issue
Preprint (not a paper): ‘Cerebral venous thrombosis: a retrospective cohort study of 513,284 confirmed COVID-19 cases and a comparison with 489,871 people receiving a COVID-19 mRNA vaccine’ by Maxime Taquet et al . This work is not peer-reviewed.
I am not sure if its been accepted yet after peer review, but here are some comments on it.
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Its been widely conjectured that the current path of evolution is to a more transmissive virus, causing a milder form of the disease. I did a bit of revision, based on a hunch I had some time ago that eventually SARS-COV-2 might eventually evolve into a part of the common cold complex.
Firstly there are currently many coronaviruses that effect a range of animals, but there are 4 main coronaviruses that effect humans namely OC43 and NL63 ( alpha ) 229E and HKU-1 (beta ). All these viruses are believed to have originated in bats and infected humans maybe 100s of years ago. SARS-COV-2 is also a Beta coronavirus.
Omicron already has 2 variants with 14 and 30 modifications to its genes. One paper (*see reference below as yet not peer reviewed) postulates that a fragment of 229E has re-combined with the delta strain and made it more transmissable. The symptoms on presentation seem to have changed, and are more like common cold or mild flu and in many cases are so mild that many people do not even go to the doctor.
Can we expect more recombination events, perhaps making the effect more mild? Any variant that contains more of any of those 4 cold viruses expressing spike protein or cell wall protein, would in all probability be more recognisable to our immune systems, because they do not recognise just the spike protein, thereby making them less dangerous to us while still being highly transmissable.
However, very small children can and do develop serious illness from the original 4 cold viruses, like croup for instance, and even now although not common in the west, some babies do die of the existing common cold coronavirus, so its not like the existing 4 viruses are totally benign.
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