COVID-19 vaccine research: Mixed doses result in greater boost

[snoop1130]

 

BANGKOK (NNT) - Following the National Communicable Disease Committee’s decision to allow people to receive a dose of the AstraZeneca vaccine after getting a first shot of Sinovac, because academic studies indicate that changing the vaccine improves the overall efficacy, making the inoculation equivalent to having received two AstraZeneca doses, Head of the Center of Excellence in Clinical Virology at the Faculty of Medicine, Chulalongkorn University, Prof. Dr. Yong Poovorawan, has provided a briefing on this topic.

 

Prof. Dr. Yong said the center’s teams of some 30 scientists and faculty members have been conducting about five COVID-19 vaccine research projects, so that the country can quickly benefit from its existing resources.

 

According to the center, administering a first dose of an inactivated vaccine followed by a second dose of a viral vector vaccine further stimulates the immune system. Inactivated vaccines use pathogens or virus particles that have been grown in culture and then killed to destroy disease producing capacity, so as to provide an effective immune response. After getting a first shot of an inactivated vaccine and a second shot of a viral vector vaccine, a booster effect will be generated. It is similar to the immune responses of people who have just recovered from COVID-19 and have received a vaccine dose. The center has conducted tests to verify the result.

 

At the same time, getting two shots of an inactivated vaccine will increase effectiveness against severe infection, and a third shot of a viral vector vaccine will yield a high booster effect.

 

The center’s researchers are also studying the mutation of the Delta variant of COVID-19 and the immune system. People in other countries may not be able to look into these issues as they may not use inactivated vaccines, and viral vector vaccines are not widely used in China at this time.

Prof. Dr. Yong said he has abundant information, thanks to cooperation from all sides, including a large number of volunteers.

 

With the Ministry of Public Health having adjusted its policy according to the center’s proposal, vaccine recipients’ immune responses have improved in six weeks. Normally, a viral vector vaccine produces a greater immune response when given after 12 weeks. Given the current COVID-19 situation, people cannot wait any longer.

 

The center has to maximize the use of existing resources for the benefit of medical workers. Administering a third shot of a viral vector vaccine, produces a greater boost, without having to wait for other vaccine options.

 

There is enough information about changing the vaccine as well as records of more than 1,200 people registered with the Mohpromt platform. No severe adverse reactions have been reported so far.

 

-- © Copyright NNT 2021-07-13

 

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[richard_smith237]

Erm... Sinovac efficacy 50%. *AstraZeneca efficacy 76% 

 

It doesn’t take a genius to work out that a second jab with AZ is better than a second jab with Sinovac !!! 

 

Thailand needs to get its hands on as much AZ and as much Pfizer and Moderna as possible... Thats the only way forward, I hope Thailand can manage this quickly before the virus engulfs the nation. 

 

 

(*Pre-Delta variant efficacy numbers) 

[Walker88]

Yes, two Sinovac and two Pfizer jabs are found to be as effective as two Pfizer jabs.

 

Also, two Sinovac jabs and two Moderna jabs are found to be as effective as two Moderna jabs.

[misterjames]

1 hour ago, Walker88 said:

Yes, two Sinovac and two Pfizer jabs are found to be as effective as two Pfizer jabs.

 

Also, two Sinovac jabs and two Moderna jabs are found to be as effective as two Moderna jabs.

I can't argue with those numbers:D the Chinese will be using this as an advertising slogan next.

[inThailand]

Thai expert covid researchers? 

 

Haha! 

[Lemonltr]

WHO announces that vaccines from different companies should not be mixed. There is no data and "it could be dangerous" 

[inThailand]

In twenty years, when your c..k falls off, you'll be happy you rushed out to get a jab.

 

No one knows the long term affects of these vaccines. There is a reason the pharm companies required liability protection for rushing a multi year process down to months. 

 

[pjmorton]

The registration process is very fragmented with websites being set up and taken down without notice, and registrations subject to cancellation for lack of vaccine. It's not surprising that a lot of confused, desperate people will take whatever vaccine they can get the first time and follow it with whatever they can get the second time, and so on. We had better hope that there are no ill effects from mixing and matching, because that's the only sensible way to proceed in a chaotic free-for-all situation.

[unblocktheplanet]

Well, Thailand is the first to try this. Good luck to us all!

 

The article reports a sample of 1,200 Mor Prom vaccinees. Let's see some science, antibody levels, etc.

 

And why not just start with AZ & leave Sinovac out of the equation???

[fondue zoo]

No peer review, and sounds like an attempt to justify the continued use of sinovac.  When in doubt add 30 scientists.

[WhatsNext]

Thailand being the only country in the world to try this, as far as i know anyway, could be very very wrong and cause a set of side effects that have not been tested for at all. The WHO took a while to wake up but reacted in a "don't do that" way yesterday. What's next , opening all the little bottles and just throwing it together "Thai vaccine mix".

[mtls2005]

OMG, just come up with a blanket statement...

 

The <fill in the name of an institution> has determined that <fill in any combination of vaccines/quantities> has been shown to be effective.

 

Or,  "Look you cretins, you'll take whatever vaccine we give you and you'll like it. If you don't then off to jail."

 

This is getting ridiculous. 

 

They are confusing the public with all these pronouncements in search of a "plan". And the public will (has?) stop trusting the regime, and will grow frustrated, and either OD on vaccines, or skip them altogether.

 

 

 

 

 

[fondue zoo]

 

There is an article via Reuters that states mixing vaccines is not a good idea.

 

 

[richard_smith237]

2 hours ago, fondue zoo said:

 

There is an article via Reuters that states mixing vaccines is not a good idea.

 

You have failed to provide any information to back up your claim.

 

There is no Reuters article which states mixing vaccines is not a good idea. 

 

You may have been referring to and misread / misunderstood this article which advised against individuals making their own choices to mix vaccines instead of leaving such choices to public health authorities.

 

https://www.reuters.com/business/healthcare-pharmaceuticals/who-warns-against-mixing-matching-covid-vaccines-2021-07-12/

 

 

This Reuters article states ‘a mix and match approach boosts immune response’.

 

https://www.reuters.com/world/uk/immune-response-astrazeneca-shot-boosted-by-mixing-dose-schedule-with-pfizer-2021-06-28/

 

 

 

 

 

[djayz]

Why do the constantly try to reinvent the wheel? There are now much more reliable and effective doses on the market. 

[placeholder]

21 hours ago, richard_smith237 said:

Erm... Sinovac efficacy 50%. *AstraZeneca efficacy 76% 

 

It doesn’t take a genius to work out that a second jab with AZ is better than a second jab with Sinovac !!! 

 

Thailand needs to get its hands on as much AZ and as much Pfizer and Moderna as possible... Thats the only way forward, I hope Thailand can manage this quickly before the virus engulfs the nation. 

 

 

(*Pre-Delta variant efficacy numbers) 

Actually, that's not necessarily true. Virologists have done experiments concerning a phenomenon called heterologous prime boost. Basically it means that combining 2 different vaccines can be more effective than 2 doses of the same vaccine. I'm not claiming that such is the case here. But it can't be ruled out. It also can't be ruled out that even if the proposed regimen isn't as effective as 2 doses of the AZ vaccine, it may still be effective enough. 

[stephenterry]

No vaccine has been tried and tested long term. Clearly preventable side effects, some serious to health has already occurred, which makes me reluctant to participate. However, there are long-term tried and tested drugs available which could be utilised beneficially for the early stages of infection, such as the Thai herbal flu vaccine and Ivermectin. In the latter case, it treats any variant because it blocks the virus protein spike entering the human cells. 

 

 

[J Town]

Currently, three vaccines are authorized and recommended in the United States to prevent COVID-19:

Pfizer-BioNTech

Moderna

Johnson & Johnson / Janssen

 

The US has shown great progress in opening businesses and schools. Major sports events and concerts are open to those who are vaccinated. Over 99% of those in hospitals due to Covid are unvaccinated. Those in charge in Thailand could redirect their efforts and make just as much money purchasing the above three vaccines AND look like heroes in the process. I just don't get it.

 

https://www.cdc.gov/.../vaccines/different-vaccines.html

[Rimmer]

A misleading post and replies have been removed

[richard_smith237]

3 hours ago, placeholder said:

Actually, that's not necessarily true. Virologists have done experiments concerning a phenomenon called heterologous prime boost. Basically it means that combining 2 different vaccines can be more effective than 2 doses of the same vaccine. I'm not claiming that such is the case here. But it can't be ruled out. It also can't be ruled out that even if the proposed regimen isn't as effective as 2 doses of the AZ vaccine, it may still be effective enough. 

I believe this research was based on boosting a Viral Vector / adenovirus vaccine (such as AstraZeneca) with an mRNA vaccine (such as Pfizer). 

 

There is no information on boosting an Inactivated Virus (Sinovac) with a Viral Vector vaccine (AstraZeneca).

 

But, as two doses of Sinovac are reported to have an efficacy of 50% and a single dose of AstraZeneca is reported to have an efficacy of 59-86% after the first dose it would stand to reason that a follow up dose of AstraZeneca is an improvement (unless of course there are proven complications, I’ve not read of any).

 

 

 

 

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01115-6/fulltext

 

 

[nowhereman]

Prof. Dr. Yong Poovorawan is a well paid clown.

Edited July 14, 2021 by nowhereman

[placeholder]

48 minutes ago, richard_smith237 said:

I believe this research was based on boosting a Viral Vector / adenovirus vaccine (such as AstraZeneca) with an mRNA vaccine (such as Pfizer). 

 

There is no information on boosting an Inactivated Virus (Sinovac) with a Viral Vector vaccine (AstraZeneca).

 

But, as two doses of Sinovac are reported to have an efficacy of 50% and a single dose of AstraZeneca is reported to have an efficacy of 59-86% after the first dose it would stand to reason that a follow up dose of AstraZeneca is an improvement (unless of course there are proven complications, I’ve not read of any).

 

 

 

 

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01115-6/fulltext

 

 

The trouble is you can't do arithmetic when it comes to biology.  Especially when it comes to HPB. Some combinations of vaccines are more potent than when each one is given twice. It just isn't known..

[nowhereman]

21 minutes ago, placeholder said:

The trouble is you can't do arithmetic when it comes to biology.  Especially when it comes to HPB. Some combinations of vaccines are more potent than when each one is given twice. It just isn't known..

Exactly, clinical trials trough a longer period of time and pair reviews of the study could give a reasonable answer to this enigma. But in Thailand a blind commercial can do miracles. 

Edited July 14, 2021 by nowhereman

[richard_smith237]

8 minutes ago, nowhereman said:

16 minutes ago, placeholder said:

The trouble is you can't do arithmetic when it comes to biology.  Especially when it comes to HPB. Some combinations of vaccines are more potent than when each one is given twice. It just isn't known..

Exactly, clinical trials trough a longer period of time and pair reviews or the study could give a reasonable answer to this enigma. But in Thailand a blind commercial can do miracles. 

Why the Thailand bash ? The efficacy of mixed vaccines is not only being investigated internationally a number of countries are already employing such methods (i.e. Germany with AZ followed up with Moderna)

 

I have personally followed up an initial AZ vaccination issued in Thailand with a Pfizer vaccination a month later issued internationally. 

[J Town]

Just now, richard_smith237 said:

Why the Thailand bash ? The efficacy of mixed vaccines is not only being investigated internationally a number of countries are already employing such methods (i.e. Germany with AZ followed up with Moderna)

 

I have personally followed up an initial AZ vaccination issued in Thailand with a Pfizer vaccination a month later issued internationally. 

You are one of the few who has enjoyed such a luxury. The majority of us peasants have been told we can get vaccinated by registering on numerous websites only to find we were misled.

 

The US has been very successful with their three vaccines - Johnson & Johnson/Janssen, Moderna and Pfizer-BioNTech - none of which are made available to us.

 

Thai officials are only allowing vaccines that are less efficient, for reasons unknown to us little people, but with the history of brown envelopes in LOS, it would follow logic that money is changing hands for favoring these vaccines. Hence the Thai bashing.

[richard_smith237]

42 minutes ago, J Town said:

You are one of the few who has enjoyed such a luxury. The majority of us peasants have been told we can get vaccinated by registering on numerous websites only to find we were misled.

 

The US has been very successful with their three vaccines - Johnson & Johnson/Janssen, Moderna and Pfizer-BioNTech - none of which are made available to us.

 

Thai officials are only allowing vaccines that are less efficient, for reasons unknown to us little people, but with the history of brown envelopes in LOS, it would follow logic that money is changing hands for favoring these vaccines. Hence the Thai bashing.

Yes... I was sick of paying 2500 baht each time I needed an Affirmation of Residence document from the Embassy, so a couple of years ago I went through the process of getting  Yellow House Book (and Pink ID). 

With this I registered with the Mor Promp app - there’s a running thread debating the the virtues of the Yellow house book and Pink ID (some just don’t want to accept that its useful). Anyone in Bangkok with the Pink ID and Yellow House book have been able to secure vaccination, so have some (not all) outside of Bangkok where vaccines have been made available to Thai’s. 

 

The Thai vaccine roll out for Thai’s has been utterly atrocious, foreigners have simply been forgotten about with the exception of intermittent announcements and momentary efforts with a flawed and untested registration methods.

 

The underlying issue is of course ‘money’ - Those nations which have secured vaccines did so financially well in advance of testing and production last year hedging their bets across all the big pharmaceutical companies. 

 

Thailand did not get the ‘jump’ on the vaccines and may well have believed that they could avoid serious consequences of the Covid-19 breakout by maintaining its Emergency Decree and tight border controls while at the same time hoping the rest of the world would control and even perhaps eradicate Covid-19. 

 

Now that virus eradication is obviously not the case Thailand has entered a stage of vaccine panic and has been unable to secure sufficient vaccine for its population. Sinovac, while better than nothing may not be sufficient to maintain herd immunity.

 

It is important that Thailand secures ‘better vaccines’ (better efficacy) as quickly as possible.

It is important that Thailand vaccinates those in areas of high population density (prisons, slums, factories, immigrant labourer accommodation, those working in markets etc), and of course, it is also important that Thailand vaccinates first those in high risk groups (those with risk illnesses and the aged).

 

Of course, everyone knows this - the simple issue, which isn’t really a simple issue at all is that Thailand cannot get its hands on sufficient numbers of vaccines - it needs Millions of AZ, Pfizer, Moderna or even Janssen vaccines and it needs them now before the explosion of cases leads to homegrown antigenic drift and the virus evolves / mutates into a variant against which the current crop of vaccines are ineffective. 

 

For this reason it is important that every nation, not just Thailand gets vaccinated and further more dangerous variants are prevented from evolving.