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Brazil Rejects the Gamaleya Vaccine

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Re: Brazil Rejects the Gamaleya Vaccine

#91
post #50

Earlier quoted context omitted.

> Anvisa says that among the vast majority of replication deficient vectors some replication-able viruses were present. Do you have the source for this claim? Linked Anvisa slides page 6 says "todos os lotes" (all lots) had replicating virus. I agree this is about quality control and it is extremely unlikely to affect vaccine efficacy. (If anything, it would improve vaccine efficacy.)

I will try to find the source again, however I would read todos os lotes as saying that there are detectable replicant viruses. Replicant viruses do not carry the spike protein, they don't contribute to antigen protection.

> Replicant viruses do not carry the spike protein, they don't contribute to antigen protection.

Are you sure? Do you mean that all of them must have had recombination that added the E1 gene and dropped the spike protein?

Re: Brazil Rejects the Gamaleya Vaccine

#92

Virologist Dr. Angela Rasmussen about the ability of the vector virus to replicate https://mobile.twitter.com/angie_rasmussen/status/1387397186...

In the linked Twitter thread, Dr Rasmussen says that a consequence of the Ad5 vector becoming replication competent is that the E1 gene might have replaced the spike protein, rendering the vaccine ineffective.

Are there any other consequences to the Ad5 vector virus being able to replicate? Is the virus harmful to humans in any way, or does it have the potential to become harmful?

Re: Brazil Rejects the Gamaleya Vaccine

#93

For me, this really calls into question the efficacy numbers published for the Gamaleya vaccine. e.g.: The Gamaleya National Research Center of Epidemiology and Microbiology and the Russian Direct Investment Fund (RDIF) have reported that the Sputnik V Covid-19 vaccine showed a 97.6% efficacy. [0] [0]: https://www.pharmaceutical-technology.com/news/russia-sputni...

You cannot trust the Brazilian government to make this judgement. It is a policy of that government to delay the approval of vaccines as much as possible, as if there was no actual pandemic going on. Other governments around the world have analyzed the vaccine, including Argentina and Mexico, and they're using it without any problems.

Argentinian government basically told it's own version of anvisa to approve the vaccine. That's it.

Re: Brazil Rejects the Gamaleya Vaccine

#94

A reminder that "U.S. officials pushed Brazil to reject Russia’s coronavirus vaccine" [0] for political reasons. > Under a section titled “Combating malign influences in the Americas,” the HHS report states that countries including Russia “are working to increase their influence in the region to the detriment of US safety and security.” The global affairs office coordinated with other U.S. government agencies “to dis…

Brazil is using the Chinese vaccine. Don't think they would if those claims were true

Re: Brazil Rejects the Gamaleya Vaccine

#95
post #50

Earlier quoted context omitted.

The vaccines delivered to Brazil also have a replication deficient Ad5 vector, Anvisa says that among the vast majority of replication deficient vectors some replication-able viruses were present. There is pretty much no chance at all that this affects efficacy.

> Anvisa says that among the vast majority of replication deficient vectors some replication-able viruses were present. Do you have the source for this claim? Linked Anvisa slides page 6 says "todos os lotes" (all lots) had replicating virus. I agree this is about quality control and it is extremely unlikely to affect vaccine efficacy. (If anything, it would improve vaccine efficacy.)

> I agree this is about quality control and it is extremely unlikely to affect vaccine efficacy. (If anything, it would improve vaccine efficacy.)

I don’t think you can say this with much certainty, if the viruses either regained or never lost E1, it’s also possible that the same is true with E3 which modulates immune response.

Also, either of these genes could’ve replaced the Coronavirus spike protein.

Re: Brazil Rejects the Gamaleya Vaccine

#96

Earlier quoted context omitted.

Lancet seems to be a respected journal and it confirms those numbers.

The Lancet didn't perform those tests, they only published the numbers provided by researchers overseeing the trials. The first author of the source paper is Denis Logunov [0] who works at the Gamaleya Research Institute [1]. [0] https://www.thelancet.com/journals/lancet/article/PIIS0140-6... [1] https://g.co/kgs/u6wvJ8

Scientific journals do not perform medical tests.

Re: Brazil Rejects the Gamaleya Vaccine

#97
I'm a complete layman but reading about the replication prevention I wonder:

Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold.

Common cold once vs potential death is not the worst trade-off imaginable, if you ask me.

Re: Brazil Rejects the Gamaleya Vaccine

#98

Covid19 has been extremely politicized in Brazil. President's supporters were mostly against vaccine until coronvac (sinovac vaccines) was approved by anvisa, Brazil's equivalent to FDA. In Brazil this pandemic took ridiculous proportions. In the beginning, it was said that it wouldn't kill even 800 people[0]. It was said that it would be no more than a little flu and that children should not skip schools[1]. After t…

You make a good case, but you do have to admit that Narendra Modi is also a solid contender for shittiest handling of COVID. Just letting the Kumbh Mela go ahead this year earns him a spot near the top.

Live by ideology, die by ideology.

I am not trying to defend the Indian PM, whom I barely know by name, but it is not as if the West does not have similar weaknesses. Mass BLM rallies were allowed to go forward because the political price for banning them and enforcing the ban through use of force would have been too high. Even though it was already known that going to rallies is a risky behavior.

Fortunately for the U.S. at that moment, no extra infectious variant was in circulation. AFAIK India has a nasty variant that makes things worse.

Re: Brazil Rejects the Gamaleya Vaccine

#99

I'm a complete layman but reading about the replication prevention I wonder: Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold. Common cold once vs potential death is not the worst trade-off imaginable, if…

Gamaleya themselves says they removed E1. There is no reason to doubt it.

Re: Brazil Rejects the Gamaleya Vaccine

#100

I'm a complete layman but reading about the replication prevention I wonder: Could it be that they left E1 intact deliberately? I suppose (naively) that a virus that replicates should cause a stronger immune system response and therefore increase efficacy. Being an adenovirus the worst thing that could happen is that you get a common cold. Common cold once vs potential death is not the worst trade-off imaginable, if…

This is addressed in the article:

Now, there have been debates over the years about whether you’d get a more effective vaccine that way, with a “replication-competent” adenovirus, but generally it’s believed that you can do fine with the “replication-incompetent” ones, which let you *not* give your patients a new viral infection at the same time.

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