Thailand to combine Sinovac, AstraZeneca vaccine doses to boost protection - minister

[Eric Loh]

39 minutes ago, grandpa said:

So 140 days after the second dose it is only 15% effective! That is only just over 4 months! No use at all! Are people who have had 2 shots of Sinovac allowed to go to Phuket? Bin it, and stick to those that have a reasonably proven record!  Although, nothing is certain, even if you can get vaccinated!

Scientific conclusion not based on extrapolation. 

[pentagara]

1 hour ago, wensiensheng said:

I think the point that has drifted out of focus on a lot of posts is that Thailand is not talking about using one shot of  AZ and one shot of an mRNA vaccine. That combo HAS been used in some countries and as, as someone posted, it’s what Angela merkel did.

 

what Thailand is doing, to combat the delta strain,  is using one dose of sinovac and one dose of AZ. The issue here being that 2 doses of sinovac is not perceived as enough protection, so it’s being cut to just the one, and AZ added.

 

but AZ is perceived as only marginally better than sinovac against delta, or at least it’s own effectiveness is drastically cut.

 

in layman’s terms it’s weakest vaccine plus next less weakest vaccine.

 

whereas, AZ plus an mRNA would in layman’s terms be described as second least effective plus one of the “best”.

 

so if sinovac is a 1, and AZ a 2, and an mRNA a 3, what Thailand is doing adds up to 3. The other combo being used in other countries adds up to 5.

 

I deliberately haven’t gone into detail about actual percentage protection provided etc etc, I’m just trying to point out why people may perceive what Thailand is doing as being less than ideal. Basically it’s the inclusion of sinovac as one of the constituents in the combo.

Interesting calculation. It's unfortunately not that easy, though.

 

Example: Two doses of Astra taken two weeks apart will have crappy protection. Two doses of Astra taken 12 weeks apart will have much better protection. Reason: vector. So 2+2 does not make 4 in this case, even if it's two AZ in both cases. For this there's data and the reason is known as well.

 

Likely consequence:

1 dose of Sinovac plus one dose of AZ after four weeks should have better protection than 2 doses of AZ within 4 weeks. That's likely, but to be verified.

 

Similarly: Where would you put the one dose J&J in your calculation? Based on a recent study (albeit with very low numbers) the efficacy of J&J against delta increases (!) over time and from the start is better than AZ's two dose efficacy against delta. Potential reason (not really fully confirmed yet): AZ uses the same vector twice.

 

As for 2 mRNA within four weeks: It's unclear how that compares to one Sinovac plus one AZ within four weeks. Usually heterological combinations train the immune system better, but there's no data. Maybe/Probably better, maybe same, maybe worse. 

 

In any case, both the combination of 2 mRNA or even one mRNA plus one other vaccine is unavailable to people in Thailand right now. So why bother about theoretical options. Yes, if there would be a glut of mRNA in Thailand right now (like there is in the US), mRNA would ve a good choice.

 

Right now, where Thailand has some Sinovac and a bit more Astra, a mix of the two makes sense.

 

 

 

[Srikcir]

Mix Green with Yellow and you get Brown. 

So much allegory that dooms medical science and places the Thai population onto a petri dish for human experimentation in exchange for political loyalty.

[smedly]

4 minutes ago, pentagara said:

Right now, where Thailand has some Sinovac and a bit more Astra, a mix of the two makes sense.

no it doesn't 

 

sorry but your whole post is based on ..............................mostly "your opinion" without any hard facts or studies for most of it

 

It really is just an opinion piece which of course you are fully entitled to have - but lets be clear about what it is.

[pentagara]

Just now, smedly said:

no it doesn't 

 

sorry but your whole post is based on ..............................mostly "your opinion" without any hard facts or studies for most of it

 

It really is just an opinion piece which of course you are fully entitled to have - but lets be clear about what it is.

fully agreed, there's a lack of data.

[Surelynot]

1 minute ago, pentagara said:

fully agreed, there's a lack of data.

What kind of a comeback is that?...........pfft!

[wensiensheng]

1 minute ago, pentagara said:

Interesting calculation. It's unfortunately not that easy, though.

 

Example: Two doses of Astra taken two weeks apart will have crappy protection. Two doses of Astra taken 12 weeks apart will have much better protection. Reason: vector. So 2+2 does not make 4 in this case, even if it's two AZ in both cases. For this there's data and the reason is known as well.

 

Likely consequence:

1 dose of Sinovac plus one dose of AZ after four weeks should have better protection than 2 doses of AZ within 4 weeks. That's likely, but to be verified.

 

Similarly: Where would you put the one dose J&J in your calculation? Based on a recent study (albeit with very low numbers) the efficacy of J&J against delta increases (!) over time and from the start is better than AZ's two dose efficacy against delta. Potential reason (not really fully confirmed yet): AZ uses the same vector twice.

 

As for 2 mRNA within four weeks: It's unclear how that compares to one Sinovac plus one AZ within four weeks. Usually heterological combinations train the immune system better, but there's no data. Maybe/Probably better, maybe same, maybe worse. 

 

In any case, both the combination of 2 mRNA or even one mRNA plus one other vaccine is unavailable to people in Thailand right now. So why bother about theoretical options. Yes, if there would be a glut of mRNA in Thailand right now (like there is in the US), mRNA would ve a good choice.

 

Right now, where Thailand has some Sinovac and a bit more Astra, a mix of the two makes sense.

 

 

 

Yes, I wasn’t really trying to actually make a calculation, more trying to illustrate what the current perception might be in Thailand generally atm. I have no medical training and there are precious few research studies done, so actual calculations are impossible.

 

1. Yes, 1 sinovac + 1 AZ may be better than 2 AZ in the short term. The issue maybe that it has been said that the sinovac protection wanes rather quickly. Not verified of course. And the point I was making was more to contrast between sinoAZ and AZ/mRNA, rather than sinoAZ and AZx2. But sure, what you say is definitely possible.

 

2. I didn’t really consider j and j tbh. I haven’t read anything about combining that with another vaccine. I’m guess that were people in Thailand offered a choice, they would opt for j and j over sinovac x2, sinoAZ, or AZx2. Pure speculation on my part.

 

3. Afaik, mRNA jabs are usually more than 4 weeks apart. I’m not sure that there are any studies that compare 2 mRNA jabs against a sinoAZ combo. So yes, unclear. Personally, I’m not so worried about the 4-16 week short term whilst jabs are delivered and start to take effect, for myself I am more concerned with the following 12 months. If I need a booster after 12 months, presumably I could get one.

 

4. At this very moment, you are right mRNA is not available in Thailand, period. But that could change in coming months. And for some, they might decide the lure of an mRNA is such that they would actually fly to their home country to get it. I am not saying that mRNA is a silver bullet, far from it. But some might decide to wait rather than go for a sinoAZ combo.

 

whether a sinoAZ combo makes sense right now, I really don’t know. I’m not a doctor and since there aren’t any verifiable studies that have been done, I can’t make an informed decision.

 

i guess I would sum up by saying that the situation over the next six months seems kind of fluid. Quite hard to make a definite choice and say, yup, that’s the best course of action.

[placeholder]

13 minutes ago, Srikcir said:

Mix Green with Yellow and you get Brown. 

So much allegory that dooms medical science and places the Thai population onto a petri dish for human experimentation in exchange for political loyalty.

Science by metaphor? A revolutionary approach!

[wensiensheng]

9 minutes ago, Surelynot said:

What kind of a comeback is that?...........pfft!

What’s wrong with agreeing with a valid point that’s been made? 

[Xonax]

Does this mean, that the government will cancel all pending orders for Sinovac, or is the money to be made on Sinovac deals too hard for them to miss out on?

[DirtyHarry55]

Not sure that's a great idea?

WHO warns against mixing and matching COVID vaccines

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

[Surelynot]

3 minutes ago, wensiensheng said:

What’s wrong with agreeing with a valid point that’s been made? 

You don't do humor?

[Surelynot]

5 minutes ago, placeholder said:

Science by metaphor? A revolutionary approach!

Mixed with a cliche.....think you are onto a winner.

[Surelynot]

4 minutes ago, Xonax said:

Does this mean, that the government will cancel all pending orders for Sinovac, or is the money to be made on Sinovac deals too hard for them to miss out on?

People will continue to get a first shot of Sinovac until it is used up, I suspect.

[wensiensheng]

2 minutes ago, Surelynot said:

You don't do humor?

You got me 5555

[dlclark97]

Does the esteemed minister have any medically documented proof these vaccines can be successfully mixed.  Somehow I have doubts.  

[dlclark97]

Take a look at what Singapore is doing for those persons vaccinated with Sinovac vaccine.  Basically these people when and where testing is needed are being treated as if they had had no vaccinations at all.  It would probably kill a few fish but that vaccine should be flushed.  Those in charge must rearrange their priorities and get all persons living in Thailand vaccinated with the highest quality vaccines available.  Only when that has been done can their thoughts be returned to the economy and reopening the country.  Delaying further may just decimate the whole country, totally destroying its economy and any thoughts of it ever becoming a highly sought after and booming tourist destination again.

[Bkk Brian]

15 minutes ago, pentagara said:

Interesting calculation. It's unfortunately not that easy, though.

 

Example: Two doses of Astra taken two weeks apart will have crappy protection. Two doses of Astra taken 12 weeks apart will have much better protection. Reason: vector. So 2+2 does not make 4 in this case, even if it's two AZ in both cases. For this there's data and the reason is known as well.

 

Likely consequence:

1 dose of Sinovac plus one dose of AZ after four weeks should have better protection than 2 doses of AZ within 4 weeks. That's likely, but to be verified.

 

Similarly: Where would you put the one dose J&J in your calculation? Based on a recent study (albeit with very low numbers) the efficacy of J&J against delta increases (!) over time and from the start is better than AZ's two dose efficacy against delta. Potential reason (not really fully confirmed yet): AZ uses the same vector twice.

 

As for 2 mRNA within four weeks: It's unclear how that compares to one Sinovac plus one AZ within four weeks. Usually heterological combinations train the immune system better, but there's no data. Maybe/Probably better, maybe same, maybe worse. 

 

In any case, both the combination of 2 mRNA or even one mRNA plus one other vaccine is unavailable to people in Thailand right now. So why bother about theoretical options. Yes, if there would be a glut of mRNA in Thailand right now (like there is in the US), mRNA would ve a good choice.

 

Right now, where Thailand has some Sinovac and a bit more Astra, a mix of the two makes sense.

 

 

 

Let me add some figures/percentages for you from credible studies (with links) that leads to the conclusion that this is not a good idea at all.

 

AZ and Pfizer with Delta Variant 

AZ: 33% effective after one dose, 60% effective after two against symptomatic disease.

92% effective against hospitalisation after 2 doses

 

Pfizer: 33% effective after one dose, 88% effective after two against symptomatic disease.

96% effective against hospitalisation after 2 doses

 

Sinovac with Delta Variant

Zero international studies published the only local study by Thailand being this one 

Thai study finds 2 doses of Sinovac can’t beat Delta variant

 

Sinovac with original strain covid-19 (study from Chile University)

3% effective after one dose, 88% effective after two against symptomatic disease.

 

In effect adding a combo of Sinovac first dose with 3% or much likely less effectiveness, to a second shot with AZ is like carrying out an experiment and hoping it works with absolutely no proof of logical science behind it.

 

Its a recipe for complete disaster

 

[wensiensheng]

8 minutes ago, dlclark97 said:

Does the esteemed minister have any medically documented proof these vaccines can be successfully mixed.  Somehow I have doubts.  

Fwiw, I think there are supposed to be 3 local studies that “prove” a sinoAZ combo is as good as 2 AZ. But they must be very short duration and I haven’t seen any details as to scope or scale. 

 

make of that what you will. The cynic in me says the government told Thai medics to come up with evidence to say what they are doing is ok. Others might feel it’s satisfactory evidence. Who knows?

[jerrymahoney]

Opas Karnkawinpong, director-general of Thailand’s Department of Disease Control

[Derek B]

Variant D is the game changer.

 

Variants will dictate the form of vaccination policies globally.

[Eric Loh]

7 minutes ago, dlclark97 said:

Take a look at what Singapore is doing for those persons vaccinated with Sinovac vaccine.  Basically these people when and where testing is needed are being treated as if they had had no vaccinations at all.  It would probably kill a few fish but that vaccine should be flushed.  Those in charge must rearrange their priorities and get all persons living in Thailand vaccinated with the highest quality vaccines available.  Only when that has been done can their thoughts be returned to the economy and reopening the country.  Delaying further may just decimate the whole country, totally destroying its economy and any thoughts of it ever becoming a highly sought after and booming tourist destination again.

The same goes to Astrazeneca which will not included in the Singapore's national count. The reason is that the National Vaccination Program is still vetting data from Sinovac. Safety profile data of vaccinated people are also will be collected for approval evaluation. So far, almost 20,000 people have been vaccinated with Sinovac. 

[David T Pike]

"There have been no studies specifically on mixing Sinovac and AstraZeneca released".  

 

 So there are some "unreleased" ones they don't want us to see?  Hmmm.... ????

 

  Pay no attention to that alien baby popping out of your chest! Nothing to see here... Move along....

[Surelynot]

Just now, Derek B said:

Variant D is the game changer.

 

Variants will dictate the form of vaccination policies globally.

Agree....quoting effectiveness is meaningless without specifying which variant...............and at the moment it seems Moderna and Pfizer (Thais will never be able to use Pfizer) and the only leading lights.

[skippybangkok]

Vaccine Stroll-Out is a new term 

[Bernietravelling]

17 hours ago, snoop1130 said:

Thailand will use AstraZeneca Plc's COVID-19 vaccine as a second dose for those who received Sinovac's shot as their first dose

 

AstraZeneca - really ?

 

Denmark and Norway stopped using AstraZeneca because of the associated side risks, like blood clotting.

 

And now the Thai Health reinvents the wheel and intends to use that AstraZeneca as booster shot after using Sinovac...

As a result, that means:

 

Adding to the already existing risks

another potential risk from the combination.

 

There aren’t any studies -even such preclinical studies with animals -

which could exclude that the combination of Sinovac with AstraZeneca is not worsening the side effects.

 

 

 

... in all leaflets in your typical box of other pharmaceuticals,

you find some substances listed, where trials and studies showed, 

you shouldn’t combine them with the pharmaceutical, you bought.

 

However, for vaccines directly injected in your body, you don’t need such studies?

 

 

 

Edited July 13, 2021 by Bernietravelling

[dutchweller]

So basically the same as everything that you buy.

Buying cheap Chinese garbage is always a more costly than paying for a slightly more expensive better made product.

I learnt this years ago when shopping at the markets in Thailand.

It seems like a good idea but if you want it to last stay away from anything Chinese.

 

[SooKee]

The lack of studies in the West on the efficacy / safety of mixing Sinovac with other vaccines doubtless stems from the fact that Sinovac is considered to be such garbage that it doesn't even feature on their list of approved vaccines at all, not even at the bottom, let alone a vaccine to be tested in a combo study.

 

The 'Thailand World 1st' strap-line for their Sino/AZ 'experiment' makes me shudder in all honesty and the results of Thai studies I fear would not be worth the paper they're paid to be written on.  I have the option of getting AZ next week and then Moderna when it arrives.  At least the AZ (albeit not the brands of AZ available here) / MRNA combo has actually been tested but it looks to be at least as much as a result of many countries dumping (or running out of) AZ, and therefore needing a second dose option, than the science determining following long term trials that it's a good idea.  That, coupled with the WHO suggesting it's not a good idea to decide for yourself to opt for a combo, means I'll likely pass on the AZ shot unless I get a "Dear John" mail along the lines of 'sorry we can't fulfil your Moderna order'. 

Edited July 13, 2021 by SooKee

[wasabi]

No matter what happens Thailand will be #1 hub of hubs and it will have been the plan all along (once they eventually get it right)

[Isaan sailor]

56 minutes ago, Xonax said:

Does this mean, that the government will cancel all pending orders for Sinovac, or is the money to be made on Sinovac deals too hard for them to miss out on?

I don’t think they can cancel their SinoVac contract.  It may extend throughout this year into next.  That would explain why they keep stonewalling Pfizer and Moderna.  Neither one ordered yet.