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Are vaccines the light at the end of the tunnel?


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3 hours ago, TeeRick said:

Herd Immunity can be natural (by infection/exposure) or can be acquired (through vaccinations).  Both methods require a lot of time and patience.

 

"Herd immunity" as most people understand it is mostly a phenomenon of vaccines, just by the math.  Herd immunity as I think about it is when enough people are immune, that R0 falls significantly below 1.  So if someone has the disease, it doesn't spread very far.  So the herd as a whole is immune, even if not all the individuals are.

 

This is not possible with natural transmission, because of the math.  As infections rise, and immunity rises, the R0 falls, until it reaches an equilibrium around 1.  Then the transmission basically stays at a stable rate and moving back and forth across the globe, partially seasonally as winter increases the R0 and summer decreases it, and then also moving geographically as people are born and enough people lose immunity for R0 to increase above one.   Basically how the other 4 coronaviruses work.  They are fairly stable, not like influenza, but they are with us forever.  The only problem is comparatively SARS-CoV2 is much much more severe, as the other 4 generally do not cause deaths.

 

Yes, there is some herd immunity effect as in when there is that much spread already, then the number of people who can concurrently be ill is not that high and it won't overburden the health care system, but it means basically everyone is going to get it sooner or later.

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7 hours ago, TeeRick said:

No good way around this except perhaps one- Get as many people vaccinated as possible and hope to impact transmission.  That's all you can really do. 

I would be more than happy to get a vaccine.  In my state however, I am way at the bottom of the list.

 

That is why I am concerned about those getting vaccinated and still being contagious. If those vaccinated feel safe and become lax it becomes even more of an impact for those who are not.

M

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8 hours ago, UnorigionalName said:

 

"Herd immunity" as most people understand it is mostly a phenomenon of vaccines, just by the math.  Herd immunity as I think about it is when enough people are immune, that R0 falls significantly below 1.  So if someone has the disease, it doesn't spread very far.  So the herd as a whole is immune, even if not all the individuals are.

 

This is not possible with natural transmission, because of the math.  As infections rise, and immunity rises, the R0 falls, until it reaches an equilibrium around 1.  Then the transmission basically stays at a stable rate and moving back and forth across the globe, partially seasonally as winter increases the R0 and summer decreases it, and then also moving geographically as people are born and enough people lose immunity for R0 to increase above one.   Basically how the other 4 coronaviruses work.  They are fairly stable, not like influenza, but they are with us forever.  The only problem is comparatively SARS-CoV2 is much much more severe, as the other 4 generally do not cause deaths.

 

Yes, there is some herd immunity effect as in when there is that much spread already, then the number of people who can concurrently be ill is not that high and it won't overburden the health care system, but it means basically everyone is going to get it sooner or later.

the mild corona viruses, the ones that cause the common cold, along with rhino viruses, are with use forever because immunity only lasts about a year. so you can get them same one year after year  in addition the the ones that cause similar symptoms.

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18 hours ago, ECCruise said:

OK.  There will be other providers.

But they are all exactly the same formula?  Exactly the same approach?  And all will reach 90%?

I hope so but I don't think so.  That would mean every one of these providers would be knocking on the door of the most effective vaccines in the history of medicine.  Maybe.

We can probably place a safe bet that the Moderna vaccine (at least) being similar mRNA technology will have very good efficacy results reported soon.  The other technologies are still all wait and see.  And we cannot forget the safety part of the equation in these trials.

 

Of interest, the other key new technology (adeno vectors) shared by many companies in development like AZ/Oxford and J&J still need to be proven in their phase 3 studies.  But the same adeno vector vaccine from Russia was announced to have 92% efficacy in their ongoing phase 3 study.  If that is actually the fact then the major adeno vector vaccines could add to the world supply in 2021.  We shall see.

 

https://www.cnbc.com/2020/11/11/coronavirus-vaccine-russia-says-its-vaccine-is-92percent-effective.html

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On 11/9/2020 at 10:59 AM, Dylandude said:


Fantastic news from Pfizer.

In the UK the BMA (British Medical Association) wrote to all GP’s last week to outline the start of the vaccination process which will be lead by GP’s, initially during December. At the outset Healthcare workers and the over 85’s will be offered the vaccine.

 

There is however a logistical problem ahead. It is outlined in the BBC report that the vaccine needs stored at -80C

I spoke today with a division of a huge US Pharmaceutical Wholesale & Distribution company, and they have no facility for that type of storage or distribution via vans and lorries in the UK. The lowest temperature currently available in the UK is -12C

I have also spoken with two doctors today, and no doctors surgery will have the equipment to store at that temperature either.

 

I highlighted the potential of logistical problems earlier in this thread. Having spent a career working in the Pharmaceutical Industry there are multitude of factors to allow for beyond drug discovery. My input was ridiculed by Fouremco and I stopped posting as a result. Subsequently TeeRick kept the beacon burning for sense and sensibility.

 

We have breakthrough, however, we have to find a way of getting this vaccine to everyone in as fast and as safe a way as possible.

Dylan,

This was announced by the head of R&D at Pfizer yesterday.  They are working on a dry powder formulation.  I think code for lyophilized powder.  That could be stored very stably in vials and then reconstituted prior to injection.  All would need to be validated - including some sort of equivalency study in the clinic.  So not a short term fix.  But of course if COVID or mutated versions are with us for years, having an easily manufactured and easy to modify (sequence) mRNA vaccine in a stable lyophilized powder is a very good approach.

https://www.dailymail.co.uk/news/article-8936107/Pfizers-scientist-says-working-powder-form-COVID-19-vaccine.html

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Just now, mayleeman said:

Is there any reason production could not be increased substantially by licensing to other drug companies? If one vaccine is significantly more effective that seems the solution. 

Licensing or more likely sub-contracting.  I think all channels will be explored with any of the approved COVID vaccines.   And for distribution keep in mind the COVAX program.

https://www.who.int/initiatives/act-accelerator/covax

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14 hours ago, mimbecky said:

I would be more than happy to get a vaccine.  In my state however, I am way at the bottom of the list.

 

That is why I am concerned about those getting vaccinated and still being contagious. If those vaccinated feel safe and become lax it becomes even more of an impact for those who are not.

M

I don't understand your logic.  Why would those vaccinated still be contagious?

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8 minutes ago, mek said:

I don't understand your logic.  Why would those vaccinated still be contagious?

 

It isn't my logic. I am not a doctor or in the science field.  I have however heard this across several platforms and am actually looking for some dumbed down info here from those who would understand this phenomenon. It appears some agreement here though?  TeeRick? Others in the field?

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37 minutes ago, mek said:

I don't understand your logic.  Why would those vaccinated still be contagious?

 

24 minutes ago, mimbecky said:

 

It isn't my logic. I am not a doctor or in the science field.  I have however heard this across several platforms and am actually looking for some dumbed down info here from those who would understand this phenomenon. It appears some agreement here though?  TeeRick? Others in the field?

 

There are at least a couple of challenges, first and foremost that there are still things we don't know about the SARS-CoV-2. There is what appears to be a very successful global effort at developing a vaccine less than a year after the virus was first recognized. Most previous vaccine efforts were directed at pathogens where there were decades or more of research. It's pretty apparent, for instance, that there's an asymptomatic carriage state where people are capable of transmitting the virus but have no evidence of disease. There's apparently no good consensus, other than mass screening, to account for those people in vaccine trials.

 

The current vaccine trials have primary endpoints that measure reduction in disease (symptoms). The Pfizer trial performs nasal swabs on everyone with symptoms, and their 90% reduction in disease (simplified) is that 90% fewer people in the vaccinated group developed symptoms and were PCR positive on swab (their criteria for diagnosing COVID-19, which correctly used is the disease caused by the virus, not the virus). There's no testing of asymptomatic people to see if they can recover the virus.

 

Now, the good news, I think. There's no good way to prove that vaccinated individuals can't transmit the virus. That's different from saying they do. The mechanism of all these vaccines targets a fundamental process of viral replication. That at least gives me hope, even if it can't currently be demonstrated in a clinical trial, that viral load, viral shedding, and transmission should all be reduced by the same mechanism that appears to be reducing disease. but it may be a long time before we actually know. Once enough people are vaccinated, you should see fewer asymptomatic swab positives, for instance, even in unvaccinated people, if the vaccine is blocking transmission. And if we can hit the 60-70% vaccine rate with a 90% effective vaccine, and it blocks transmission, we should stop sustained transmission (not all, unfortunately).

 

Hope that helps.

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2 hours ago, markeb said:

 

 

There are at least a couple of challenges, first and foremost that there are still things we don't know about the SARS-CoV-2. There is what appears to be a very successful global effort at developing a vaccine less than a year after the virus was first recognized. Most previous vaccine efforts were directed at pathogens where there were decades or more of research. It's pretty apparent, for instance, that there's an asymptomatic carriage state where people are capable of transmitting the virus but have no evidence of disease. There's apparently no good consensus, other than mass screening, to account for those people in vaccine trials.

 

The current vaccine trials have primary endpoints that measure reduction in disease (symptoms). The Pfizer trial performs nasal swabs on everyone with symptoms, and their 90% reduction in disease (simplified) is that 90% fewer people in the vaccinated group developed symptoms and were PCR positive on swab (their criteria for diagnosing COVID-19, which correctly used is the disease caused by the virus, not the virus). There's no testing of asymptomatic people to see if they can recover the virus.

 

Now, the good news, I think. There's no good way to prove that vaccinated individuals can't transmit the virus. That's different from saying they do. The mechanism of all these vaccines targets a fundamental process of viral replication. That at least gives me hope, even if it can't currently be demonstrated in a clinical trial, that viral load, viral shedding, and transmission should all be reduced by the same mechanism that appears to be reducing disease. but it may be a long time before we actually know. Once enough people are vaccinated, you should see fewer asymptomatic swab positives, for instance, even in unvaccinated people, if the vaccine is blocking transmission. And if we can hit the 60-70% vaccine rate with a 90% effective vaccine, and it blocks transmission, we should stop sustained transmission (not all, unfortunately).

 

Hope that helps.

 

Thanks for explaining. I think I’ve got it.

In summary, if you are vaccinated then that will significantly reduce the risk of you becoming infected. 

But if you are not vaccinated, then your risk of becoming infected remains as is. (Quite high as I understand it, since the infection spreads readily?)

As far as I can see, the losers are those who cannot or refuse to be vaccinated?

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20 minutes ago, zanderblue said:

In summary, if you are vaccinated then that will significantly reduce the risk of you becoming infected

 

Almost. The vaccine trial is designed around symptoms of the disease, COVID-19. Even the asymptomatic carriers are infected with SARS-CoV-2. So the trial so far shows you have a significantly lower risk of developing the disease (and its symptoms), but wasn't really designed to determine infection. And infection without symptoms pretty much defines the asymptomatic transmission.

 

This is where terminology has gotten out of control over the months as SARS-CoV-2 infections (test positives) have been reported as cases for months, but many if not most do not have COVID-19 (the actual disease). But the virus and its disease have almost become synonymous in most reporting, outside of journals and the like.

 

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13 hours ago, TeeRick said:

We can probably place a safe bet that the Moderna vaccine (at least) being similar mRNA technology will have very good efficacy results reported soon.  The other technologies are still all wait and see.  And we cannot forget the safety part of the equation in these trials.

 

Of interest, the other key new technology (adeno vectors) shared by many companies in development like AZ/Oxford and J&J still need to be proven in their phase 3 studies.  But the same adeno vector vaccine from Russia was announced to have 92% efficacy in their ongoing phase 3 study.  If that is actually the fact then the major adeno vector vaccines could add to the world supply in 2021.  We shall see.

 

https://www.cnbc.com/2020/11/11/coronavirus-vaccine-russia-says-its-vaccine-is-92percent-effective.html

I suspect that if Pfizer had reported a 100% efficacy the Russians would have stated that theirs was 102%.  I can find any place where they have published any phase 3 data or its equivalent.

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9 hours ago, zanderblue said:

 

Thanks for explaining. I think I’ve got it.

In summary, if you are vaccinated then that will significantly reduce the risk of you becoming infected. 

But if you are not vaccinated, then your risk of becoming infected remains as is. (Quite high as I understand it, since the infection spreads readily?)

As far as I can see, the losers are those who cannot or refuse to be vaccinated?

To piggyback onto Markeb’s excellent explanation- in the case of SARS - CoV 2, in the immediate future what you say is true, BUT, one of the goals of true herd immunity is to lower the risk of infection for persons who cannot get vaccinated. As we go along, it may well turn out that very few people will not be able to get vaccinated or more common today, won’t develop immunity from the vaccine. But there will always be a small number of people whose only protection will be herd immunity or having the infection and developing some natural immunity.

Measuring and answering some of these questions, as Markeb, Teerick and Nocl have all alluded to, may require a lot more time, a different study design and more understanding of the virus and the testing. It’s not that the study is bad, or some of the answers aren’t buried in the data or even that transmission of infection hasn’t been prevented, it’s more that safety of the vaccine and efficacy in a very broad sense and speed were the most important endpoints. It would take a lot of swabbing and testing over and over, of a lot of people in the trial to answer some of the questions we are asking. But if the efficacy holds anywhere close to the 90%, it’s a very reasonable assumption that the transmission rate has been significantly reduced - we just haven’t proven it.

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This is the caveat of running very quickly outside of the usual approaches which are normally more lengthy and thorough, with more clinical studies looking at multiple outcomes.  And starting these studies with just early understanding of a very complicated virus.  But IMO it needed to be done this way given where we are in the world situation since January.  We will clearly learn a lot from all of these studies.  We have already learned that the unproven mRNA vaccine technology has great potential for COVID and other vaccines going forward.  We really have no evidence to date that the newly vaccinated asymptomatic population will still be virus transmitters.  It could happen to some extent- or it just might not.  Let's be hopeful.

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Reading a bit more about side effects...if they are unpleasant, will folks go back for Part 2..and if they don't,  will they be partially safe?

 

Had a terrible reaction 1 yr to the flu shot but have done okay all other yrs..Hope side effects won't be too severe

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Saw this HHS article today which gives us more hope that getting a vaccine when one comes to our area will be easy to get. For us all we'll need to do is pop down to the Publix pharmacy down the street rather than having to worry about going to a nearby hospital and stand in a long line. At least that's the hope.

 

https://www.hhs.gov/about/news/2020/11/12/trump-administration-partners-chain-independent-community-pharmacies-increase-access-future-covid-19-vaccines.html

 

 

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15 hours ago, hcat said:

Reading a bit more about side effects...if they are unpleasant, will folks go back for Part 2..and if they don't,  will they be partially safe?

 

Had a terrible reaction 1 yr to the flu shot but have done okay all other yrs..Hope side effects won't be too severe

If I were to have a bad reaction to a vaccine, I would suspect that might be an indication that my reaction to getting an actual infection could be very severe. So I would certainly get the second one!

 

But I am likely a much stronger believer in vaccines than most. Anyone who is pretty reluctant in the first place might not go back, unfortunately.

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On 11/11/2020 at 9:54 AM, mayleeman said:

Is there any reason production could not be increased substantially by licensing to other drug companies? If one vaccine is significantly more effective that seems the solution. 

It may not be that easy to sub contract or license to other manufacturers.

 

Producing vaccines is not as easy as producing capsules or tablets.  

 

Facilities must have the equipment and  trained personnel to manufacture the vaccine  and there are other hurdles such as FDA inspections, approval of the site and testing to show bioavailability/bioequivalence.

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9 hours ago, Ken the cruiser said:

Saw this HHS article today which gives us more hope that getting a vaccine when one comes to our area will be easy to get. For us all we'll need to do is pop down to the Publix pharmacy down the street rather than having to worry about going to a nearby hospital and stand in a long line. At least that's the hope.

 

https://www.hhs.gov/about/news/2020/11/12/trump-administration-partners-chain-independent-community-pharmacies-increase-access-future-covid-19-vaccines.html

 

 

 

I think it depends on the state...so I would look at your state / county department of health to find out where you will be able to get it. This could change as it gets rolled out and becomes more available.

Here is an article that was printed in my local press, but came from the AP:

 

https://apnews.com/article/biggest-vaccination-effort-us-history-2d46fd529b2ff5313201e8065b81c0d7

 

 

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On 11/12/2020 at 1:16 AM, cangelmd said:

To piggyback onto Markeb’s excellent explanation- in the case of SARS - CoV 2, in the immediate future what you say is true, BUT, one of the goals of true herd immunity is to lower the risk of infection for persons who cannot get vaccinated. As we go along, it may well turn out that very few people will not be able to get vaccinated or more common today, won’t develop immunity from the vaccine. But there will always be a small number of people whose only protection will be herd immunity or having the infection and developing some natural immunity.

Measuring and answering some of these questions, as Markeb, Teerick and Nocl have all alluded to, may require a lot more time, a different study design and more understanding of the virus and the testing. It’s not that the study is bad, or some of the answers aren’t buried in the data or even that transmission of infection hasn’t been prevented, it’s more that safety of the vaccine and efficacy in a very broad sense and speed were the most important endpoints. It would take a lot of swabbing and testing over and over, of a lot of people in the trial to answer some of the questions we are asking. But if the efficacy holds anywhere close to the 90%, it’s a very reasonable assumption that the transmission rate has been significantly reduced - we just haven’t proven it.

Hi,

There are few vaccines that are perfect in all aspects (protecting all,

inducing perfect herd immunity, not causing side effects etc.).

This is a very unusual common cold virus. It KILLS many that are infected.

This is what scares most!  Also many have severe symptoms that

cause long lasting problems. Most that have issues are over 70.

As I mentioned earlier, if the vaccine eliminated DEATH and severe

symptoms it would be GREAT! If it was long lasting,  inhibited transmission

and induced herd immunity it would be a bonus! Also, some  that are

asymptomatic were really pre symptomatic which also created terminology

issue.

 

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1 hour ago, Homosassa said:

It may not be that easy to sub contract or license to other manufacturers.

 

Producing vaccines is not as easy as producing capsules or tablets.  

 

Facilities must have the equipment and  trained personnel to manufacture the vaccine  and there are other hurdles such as FDA inspections, approval of the site and testing to show bioavailability/bioequivalence.

You are correct of course but not all vaccines are created equal.  It depends on the type of vaccine.  Infrastructure is out there for more traditional vaccines such as protein subunit (like Novavax for example). There is quite a lot of Biologics infrastructure and expertise available.  There would need to be a technology transfer with validation to the contract facility.  Then approved by FDA, EMEA and other authorities depending on where the vaccine will be used.  But for the mRNA vaccines and the Adeno vaccines, a whole new ballgame.  

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