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“If the virus changes substantially, particularly the spike proteins, then it might escape a vaccine. We want to slow transmission globally to slow the clock,”

“If the virus changes substantially, particularly the spike proteins, then it might escape a vaccine. We want to slow transmission globally to slow the clock,” Is this why some are saying we might need a booster shot in a few years?

DubiousPusher 6y ago
I don't think so. I believe that is related to the immune system's ability to "forget". I believe a new strain which evades the current vaccine schemes would need an entirely new or significantly altered vaccine.
CyanBird 6y ago
No, different reason, booster shots, are needed to "remind" your immune system that the virus is still out there, and keep it on fighting shape, and as far as I am aware, the early discussions for booster shots, were about 6, to 9 months. But all of that is up in the air, there's no data for how the vaccine will develop that much into the future yet Anyhow, if the spike proteins vary too much, then we'll need a new vaccine all together, not just a booster for the current one
akkawwakka 6y ago
To correct the quoted assertion... There is little selection pressure on the virus for the spike proteins to evolve and change. SARS-CoV-2 infects human cells just fine using its current spike protein. [1] [1]: https://www.nature.com/articles/d41586-020-02544-6 https://www.nature.com/articles/d41586-020-02544-6
- divbzero 6y ago
  Thanks for that Nature news feature, it summarized the research on SARS-CoV-2 mutations quite well. We’ll have to watch for signs of selection pressure as more and more of us get vaccinated to recognize the spike protein. Hopefully SARS-CoV2 mutates too slowly to escape the vaccines, or can only escape with sharply reduced infectivity and virulence.
  - pm90 6y ago
    It’s mentioned in the nature article: > Studies of common-cold coronaviruses, sampled across multiple seasons, have identified some signs of evolution in response to immunity. But the pace of change is slow, says Volker Thiel, an RNA virologist at the Institute of Virology and Immunology in Bern. “These strains remain constant, more or less.” So there seems to be a pretty good chance that this won’t really be an issue.
- WanderPanda 6y ago
  Yay, then lets see how the spike protein evolves after mass vaccination. In my understanding the vaccination targets exactly that protein so there should be plenty of selective pressure in case mass vaccination takes place
  - pm90 6y ago
    That seems to be an incorrect understanding. Selective pressure is only one of the factors influencing how frequently the virus has mutations. Self correction mechanics in the RNAs replication seem to have a much more stronger effect, since they “correct” the mutations. The article specifically mentions that the timeline for significant mutations is likely in the order of a few years.
    - pharke 6y ago
      A slow mutation rate reduces the rate of change if all other variables are equal but increasing the selection pressure can drive that rate of change higher by clearing the field of competitors and providing only one clear path to success.
alistairSH 6y ago
As noted in sibling, the booster shots are to "remind" your immune system that an infectious bug is out there. If COVID begins to mutate in ways that make the vaccine (and anti-bodies it causes) less effective, we would be in a situation like the flu - annual vaccines based on that year's strain (which takes some guesswork). The disease is then called endemic. But, there is currently no indication COVID will become endemic. It might. It might not. We don't know, but current knowledge tends to indicate it won't.

DubiousPusher 6y ago

I don't think so. I believe that is related to the immune system's ability to "forget". I believe a new strain which evades the current vaccine schemes would need an entirely new or significantly altered vaccine.

CyanBird 6y ago

No, different reason, booster shots, are needed to "remind" your immune system that the virus is still out there, and keep it on fighting shape, and as far as I am aware, the early discussions for booster shots, were about 6, to 9 months. But all of that is up in the air, there's no data for how the vaccine will develop that much into the future yet Anyhow, if the spike proteins vary too much, then we'll need a new vaccine all together, not just a booster for the current one

akkawwakka 6y ago

To correct the quoted assertion... There is little selection pressure on the virus for the spike proteins to evolve and change. SARS-CoV-2 infects human cells just fine using its current spike protein. [1] [1]: https://www.nature.com/articles/d41586-020-02544-6 https://www.nature.com/articles/d41586-020-02544-6

divbzero 6y ago
Thanks for that Nature news feature, it summarized the research on SARS-CoV-2 mutations quite well. We’ll have to watch for signs of selection pressure as more and more of us get vaccinated to recognize the spike protein. Hopefully SARS-CoV2 mutates too slowly to escape the vaccines, or can only escape with sharply reduced infectivity and virulence.
- pm90 6y ago
  It’s mentioned in the nature article: > Studies of common-cold coronaviruses, sampled across multiple seasons, have identified some signs of evolution in response to immunity. But the pace of change is slow, says Volker Thiel, an RNA virologist at the Institute of Virology and Immunology in Bern. “These strains remain constant, more or less.” So there seems to be a pretty good chance that this won’t really be an issue.
WanderPanda 6y ago
Yay, then lets see how the spike protein evolves after mass vaccination. In my understanding the vaccination targets exactly that protein so there should be plenty of selective pressure in case mass vaccination takes place
- pm90 6y ago
  That seems to be an incorrect understanding. Selective pressure is only one of the factors influencing how frequently the virus has mutations. Self correction mechanics in the RNAs replication seem to have a much more stronger effect, since they “correct” the mutations. The article specifically mentions that the timeline for significant mutations is likely in the order of a few years.
  - pharke 6y ago
    A slow mutation rate reduces the rate of change if all other variables are equal but increasing the selection pressure can drive that rate of change higher by clearing the field of competitors and providing only one clear path to success.

alistairSH 6y ago

As noted in sibling, the booster shots are to "remind" your immune system that an infectious bug is out there. If COVID begins to mutate in ways that make the vaccine (and anti-bodies it causes) less effective, we would be in a situation like the flu - annual vaccines based on that year's strain (which takes some guesswork). The disease is then called endemic. But, there is currently no indication COVID will become endemic. It might. It might not. We don't know, but current knowledge tends to indicate it won't.