mRNA vaccines for those who may have already had Covid-19

Very interesting

by quikjraw - 2021-02-03 07:26:45

Crusty that is something we should look out for in weeks to come. 

I would say though that vaccination provides two solutions and the other being reducing transmissibility of the virus from person to another. So for this idea to fly I would expect they would need to factor in any potential increase in transmissibility between one dose and two doses?

For example after one dose of the AZ vaccine transmission is reduced by 67% but I assume this rises to much higher after two doses and makes it much less likely for your to pass on the virus to someone.

https://www.openaccessgovernment.org/astrazeneca-doses/102848/

My experience

by Gemita - 2021-02-03 08:11:26

Firstly in response to crustyg’s post, I want to say that most people do not have a serious or strong reaction to the Covid-19 vaccines, but for the few who may, it would be wise to report this to your health authorities for them to decide whether any action needs to be taken.  On crustyg’s suggestion I reported my symptoms here in the UK using the following link:

https://yellowcard.mhra.gov.uk/the-yellow-card-scheme/

But what constitutes serious symptoms, I hear you say.  Firstly you should read the leaflets given to you following your vaccination, to decide what would be a normal reaction to the vaccine, and some of the symptoms I describe below can be perfectly normal.  However if they last beyond say a 24 hour period, or your symptoms are so disabling that you have to go to bed for lengthy periods, just as you might if you got the flu, then you might decide this would constitute a serious reaction to the vaccine and it will do no harm to report this, which is what I did.

My symptoms:  after my Pfizer vaccine a few weeks ago, I developed flu like symptoms that lasted beyond 24 hours  (actually heightened/acute symptoms lasted for three days) - achy joints, high temperature, overwhelming tiredness (I had to sleep), feeling icy cold and shivery even with layers of clothing, cough, headache, sore throat.  I also had Coronavirus symptoms (which I had last April) all over again following the vaccine:  loss of appetite, loss of taste, high fever, cough and feeling very unwell, but this only lasted max 24 hours, whereas the flu symptoms lasted 3-4 days and I am still not fully recovered (with continuing chills/night sweats).  I had some shortness of breath too, but this was caused by my arrhythmias which intensified during my period of acute illness.

If I get any information or guidance from the UK authorities on whether or not to take up the second Pfizer vaccine (due on the 9th April) I will report in due course.  In the meantime, I am glad I have had the vaccine and that I am well protected.  I hope you all get your vaccines soon and I am sure most of you will not suffer any serious effects.  For me it has been a learning process and I am sure it is the same for us all until more is known about the virus and the vaccines that have been produced, but I too believe the vaccines are fundamentally safe and that we all need to be protected from this devastating virus.

John, I agree about two doses being potentially more effective for most individuals (protection/transmission-wise), but perhaps those who have had exposure to the virus already, have a higher degree of the right kind of protection to prevent illness/transmission but this obviously needs further study. 

Crustyg, thank you for posting and for all your guidance as always.  I will download the PDF later and have a good read.  I hope you and the family get your invitation very soon.

Transmissibility

by crustyg - 2021-02-03 08:44:18

I think we're too early to be able to make any evidence-based comment on people's ability to spread/continue to spread active, infective virus after vaccination (or indeed after unsuspected infection).  Early data from Israel implies that susceptibility to infection drops quite quickly after about 12days, IIRC.

But the thing that bedevils all of the so-called science and rubbish reporting in this area so far, with a few honourable exceptions, is that the 'Gold Standard' PCR test only detects viral nucleic acid patterns.  It does NOT detect intact virus.  A Chinese paper from March/April 2020 showed that it was possible to detect viral 'signature' in patient faeces weeks after clinical symptoms had passed, but the authors carefully pointed out that this did *not* mean that these people were excreting intact, infective virus.  Which makes the reported current Chinese policy of now using anal/rectal swabs for PCR testing seem very odd - far too many false positives.

To answer this question properly requires mass URT swabbing, then PCR, AND THEN virus culture to see if these people are still carrying live, infective virus.  And this is both very expensive and slow.  And it's moot whether we would learn anything from it.  Probably a simpler question, and nearly as convincing, would be to swab (for PCR) a subset of folk being vaccinated and of the positives, re-swab a couple of times after that to see when they clear the virus - which we can take as a proxy for 'No Longer Infectious.'

There are two general principles with vaccination: produce a vaccine that's *so* good that even if everyone around you is trying to infect you, *you*, the immunised one, don't get the infection - Hep-B is a good example, OR get such a large proportion of the community no longer able to carry the infectious agent that the probability of you - who can't be immunised due to health issues or contraindications to the vaccine - being exposed to the agent becomes extremely low - so called Herd Immunity.  Best example is Rubella - rubbish vaccine, not particularly effective, but if nearly everyone, boys and girls, is immunised and so unlikely to carry the virus, then pregnant women (esp. those not yet aware of their pregnancy) are unlikely to be exposed.

In all the online trolling and screaming about Herd Immunity and mandatory vaccination before schooling, it's often overlooked that there are valid medical reasons why some people just can't receive a particular vaccine - or very rarely *any* vaccine. Can't use smallpox vaccination in folk with eczema, for example (not really an issue now, we hope).  But it's clear that some anti-vaxxers have been able to hide behind this exemption, and now we see that they don't believe in any form of science.  I'm with Dirty Harry on this one: 'Opinions are like a**holes - everyone has one.'  But as H.L. Menken said, the best argument against democracy is to look at the Average Voter - and clearly this applies to me too!

That's what Oxford university have done

by quikjraw - 2021-02-03 11:21:15

You may not have seen the link to the latest Oxford university study Crusty plus it's not been peer group reviewed yet.

It states that after one dose of the AZ vaccine the people in the study were 67% less likely to spread the virus. 

This was not our NHS but a specialist part of the University. 

They did exactly what you said.

https://www.research.ox.ac.uk/Article/2021-02-02-oxford-coronavirus-vaccine-shows-sustained-protection-of-76-during-the-3-month-interval-until-the-second-dose

Herd immunity

by AgentX86 - 2021-02-03 22:38:01

The so called "herd immunity" is more than just lowering the density of carriers such that you're unlikely to come in contact with one.  It's about making the density so low that the virus doesn't replicate at a rate >1.  Eventually there is no virus to infect anyone.  ...or so goes the theory. 

In theory, reality and theory agree.  In reality, they don't.