5 ms·

A less effective vaccination keeps COVID around longer and farther than a more effective one, though, giving the virus more time and population surface to mutat

by anyfoo 5y ago

A less effective vaccination keeps COVID around longer and farther than a more effective one, though, giving the virus more time and population surface to mutate into further variants. (But still less than no vaccination.) I'm not an expert in this, so I cannot say how significant that issue is, but this is at least one potential downside that I am seeing to the vaccination being weaker for that variant. EDIT: To clarify since some have misunderstood: I did not assert that the vaccination causes higher mutation, quite the opposite. I asserted that the absence of vaccination (entirely or effectively) gives more opportunity for mutation. I understand now that there are higher order effects that make this more complex.

jdhn 5y ago
That's a fair critique. I feel like I've heard concerns about the potential for the virus to mutate because of the high level of vaccinations, but like you, I don't know how significant of an issue that is.
- tunesmith 5y ago
  I think the parent was talking about the lack of vaccinations yielding more time to mutate, not the vaccinations themselves. Viruses aren't like bacteria; they don't mutate in direct response to vaccines.
  - anyfoo 5y ago
    That is correct. My premise was that the more virus exists in absolute numbers (if the vaccine is weaker for the Delta variant), the more virus has the opportunity to mutate.
- listless 5y ago
  I also have this concern. I haven’t seen it addressed anywhere and I am but a mere layperson.
- smt88 5y ago
  What you've heard is misinformation. Vaccines reduce potential for mutation, which is both intuitive and borne out by data.
  - AndrewBissell 5y ago
    That's neither intuitive nor true in all cases. https://www.quantamagazine.org/how-vaccines-can-drive-pathogens-to-evolve-20180510/ https://www.quantamagazine.org/how-vaccines-can-drive-pathog...
- addicted 5y ago
  The virus will not mutate because of the high level of vaccinations. The virus will mutate because of the high level of unvaccinated people. The risk is when the high level of unvaccinated are in the same population with a high level of vaccinated, of the many mutations in the unvaccinated there is a greater chance that a mutation that randomly has greater tolerance to the vaccines will be naturally selected and flourish. Vaccination does not lead to more mutations, but in the absence of vaccination, resistance to vaccines does not give a mutation any advantage, so whether it flourishes or not is based entirely on other attributes. It’s only when you do have a significant population of vaccinated does the mutations created in the unvax population benefit from resistance to vaccines.
  - velcii 5y ago
    >mutations created in the unvax population benefit from resistance to vaccines. I cannot see how this is correct. Because it should be the mutations created in the vaccinated that will help the virus to survive in similar vaccinated hosts..because first of all, the mutated virus need to survive in the vaccinated host, and become the dominant one in that host and thus giving it a better chance to jump to another host... So this mutations must be happening in Vaccinated hosts. In unvaccinated as you said, any mutations that gives the virus immune escape capability does not give it an advantage over the other mutations in the same host, simply because there is no vaccine generated antibodies to kill the other mutations, for it to gain dominance.
  - tunesmith 5y ago
    I haven't been able to get a straight answer to this even from scientists on science threads... Given the following: 1. Virus mutations do not directly react to the vaccine. These are simply random mutations. 2. If a mutation occurs that has a higher probability of escaping an existing vaccine, then in one unvaccinated person, that mutation has an identical chance of occurring whether that person is part of a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community. 3. Natural selection just means its ability to reproduce. Let's say that the mutation can escape the vaccine at 100% probability. Then: Can that virus spread equally regardless of whether it's a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community? Because it sure sounds like people are saying that in that scenario, the mutation spreads less in a 0% community, and more in a 50% community. Are they saying that in a "mostly unvaccinated" community, the other variants (that the vaccine protects against) that are more prevalent somehow serve to "crowd out" the mutation? Because I don't know if that's true - at least, I've seen reports that suggest that people can catch more than one variant at one time.
- anyfoo 5y ago
  Just to clarify: That is not my concern.
MisterBastahrd 5y ago
It's going to mutate regardless of how many people are vaccinated. The entire point is to make it so that people don't have the runaway immune system responses that are melting lungs and brains.
- anyfoo 5y ago
  Is that true? Intuitively, the more virus exists (in absolute numbers, even), the more virus may potentially mutate into worse variants. More infected people -> more individual virus instances, each with a given chance to mutate, and more time for that mutation to occur (because expired virus is replenished with fresh virus in available hosts; though you can probably fold this into higher virus numbers instead with the same result). I'm gladly corrected if I missed something!
  - totony 5y ago
    Variant that achieve immune escape from vaccine-induced immunity are bound to propagate at a faster rate if most people are vaccinated. Even if that variant is more lethal (from which you might expect a smaller R0), it might be prevalent because of an augmentation in R0 from vaccination (which might be lesser had people developed a more complete natural immunity).
- suchire 5y ago
  The likelihood of mutation is directly proportional to how widespread a virus is multiplied by the amount of time it stays that way (more specifically, the area under the curve for infections over time). Vaccination and control of spread is critical to preventing further variants
  - totony 5y ago
    Likehood of mutation might be, but spread of variants is a more complicated function. Vaccination for sure might affect how likely one variant predominates against others. Considering cross-immunization between variants with natural immunity, it might be more efficient to refrain from vaccines to give cross-immunity with a weaker variant.
weaksauce 5y ago
the fact that the delta variant came from a country that didn't have widespread vaccines dispels this notion.
- anyfoo 5y ago
  Seems perfectly in line with what I said? More virus, more time to mutate -> more mutations? I now understand that there are second order effects that make this more complex, but I don't see the contradiction right here.
  - weaksauce 5y ago
    I suppose either you edited it to change the text or the more likely event was that I misread it. yeah you're mostly correct and there are those second order effects too.
jfoster 5y ago
Is it analogous to flu? Do flu vaccines cause mutations as well? One interesting thing about covid is that it seems to be the first time humanity has collected so much data (eg. contact tracing, phylogenetics through genome sequencing, etc.) about this kind of virus, and applied modern medical knowledge in trying to combat it. It's very apparent that the overall response hasn't been nearly good enough, but it's probably also the best response there's ever been. (perhaps not the best ROI, though?)
- anyfoo 5y ago
  > Do flu vaccines cause mutations as well? That is not what I have written, please reread!
velcii 5y ago
>But still less than no vaccination.. Can you share why you think the current vaccines will reduce the mutations when we already know that they only prevent symptoms (not even reduce viral load for some variants). So given that, why do you think the current vaccines will reduce the chances for virus to mutate. To me, it appears that the current vaccines will give the exact same chance for the virus to mutate, without the vaccine, but in addition also apply selection pressure to guide the evolution to gain immune escape. So the worst of both worlds.

by anyfoo 5y ago

jdhn 5y ago

That's a fair critique. I feel like I've heard concerns about the potential for the virus to mutate because of the high level of vaccinations, but like you, I don't know how significant of an issue that is.

tunesmith 5y ago
I think the parent was talking about the lack of vaccinations yielding more time to mutate, not the vaccinations themselves. Viruses aren't like bacteria; they don't mutate in direct response to vaccines.
- anyfoo 5y ago
  That is correct. My premise was that the more virus exists in absolute numbers (if the vaccine is weaker for the Delta variant), the more virus has the opportunity to mutate.
listless 5y ago
I also have this concern. I haven’t seen it addressed anywhere and I am but a mere layperson.
smt88 5y ago
What you've heard is misinformation. Vaccines reduce potential for mutation, which is both intuitive and borne out by data.
- AndrewBissell 5y ago
  That's neither intuitive nor true in all cases. https://www.quantamagazine.org/how-vaccines-can-drive-pathogens-to-evolve-20180510/ https://www.quantamagazine.org/how-vaccines-can-drive-pathog...
addicted 5y ago
The virus will not mutate because of the high level of vaccinations. The virus will mutate because of the high level of unvaccinated people. The risk is when the high level of unvaccinated are in the same population with a high level of vaccinated, of the many mutations in the unvaccinated there is a greater chance that a mutation that randomly has greater tolerance to the vaccines will be naturally selected and flourish. Vaccination does not lead to more mutations, but in the absence of vaccination, resistance to vaccines does not give a mutation any advantage, so whether it flourishes or not is based entirely on other attributes. It’s only when you do have a significant population of vaccinated does the mutations created in the unvax population benefit from resistance to vaccines.
- velcii 5y ago
  >mutations created in the unvax population benefit from resistance to vaccines. I cannot see how this is correct. Because it should be the mutations created in the vaccinated that will help the virus to survive in similar vaccinated hosts..because first of all, the mutated virus need to survive in the vaccinated host, and become the dominant one in that host and thus giving it a better chance to jump to another host... So this mutations must be happening in Vaccinated hosts. In unvaccinated as you said, any mutations that gives the virus immune escape capability does not give it an advantage over the other mutations in the same host, simply because there is no vaccine generated antibodies to kill the other mutations, for it to gain dominance.
- tunesmith 5y ago
  I haven't been able to get a straight answer to this even from scientists on science threads... Given the following: 1. Virus mutations do not directly react to the vaccine. These are simply random mutations. 2. If a mutation occurs that has a higher probability of escaping an existing vaccine, then in one unvaccinated person, that mutation has an identical chance of occurring whether that person is part of a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community. 3. Natural selection just means its ability to reproduce. Let's say that the mutation can escape the vaccine at 100% probability. Then: Can that virus spread equally regardless of whether it's a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community? Because it sure sounds like people are saying that in that scenario, the mutation spreads less in a 0% community, and more in a 50% community. Are they saying that in a "mostly unvaccinated" community, the other variants (that the vaccine protects against) that are more prevalent somehow serve to "crowd out" the mutation? Because I don't know if that's true - at least, I've seen reports that suggest that people can catch more than one variant at one time.
anyfoo 5y ago
Just to clarify: That is not my concern.

MisterBastahrd 5y ago

It's going to mutate regardless of how many people are vaccinated. The entire point is to make it so that people don't have the runaway immune system responses that are melting lungs and brains.

anyfoo 5y ago
Is that true? Intuitively, the more virus exists (in absolute numbers, even), the more virus may potentially mutate into worse variants. More infected people -> more individual virus instances, each with a given chance to mutate, and more time for that mutation to occur (because expired virus is replenished with fresh virus in available hosts; though you can probably fold this into higher virus numbers instead with the same result). I'm gladly corrected if I missed something!
- totony 5y ago
  Variant that achieve immune escape from vaccine-induced immunity are bound to propagate at a faster rate if most people are vaccinated. Even if that variant is more lethal (from which you might expect a smaller R0), it might be prevalent because of an augmentation in R0 from vaccination (which might be lesser had people developed a more complete natural immunity).
suchire 5y ago
The likelihood of mutation is directly proportional to how widespread a virus is multiplied by the amount of time it stays that way (more specifically, the area under the curve for infections over time). Vaccination and control of spread is critical to preventing further variants
- totony 5y ago
  Likehood of mutation might be, but spread of variants is a more complicated function. Vaccination for sure might affect how likely one variant predominates against others. Considering cross-immunization between variants with natural immunity, it might be more efficient to refrain from vaccines to give cross-immunity with a weaker variant.

weaksauce 5y ago

the fact that the delta variant came from a country that didn't have widespread vaccines dispels this notion.

anyfoo 5y ago
Seems perfectly in line with what I said? More virus, more time to mutate -> more mutations? I now understand that there are second order effects that make this more complex, but I don't see the contradiction right here.
- weaksauce 5y ago
  I suppose either you edited it to change the text or the more likely event was that I misread it. yeah you're mostly correct and there are those second order effects too.

jfoster 5y ago

Is it analogous to flu? Do flu vaccines cause mutations as well? One interesting thing about covid is that it seems to be the first time humanity has collected so much data (eg. contact tracing, phylogenetics through genome sequencing, etc.) about this kind of virus, and applied modern medical knowledge in trying to combat it. It's very apparent that the overall response hasn't been nearly good enough, but it's probably also the best response there's ever been. (perhaps not the best ROI, though?)

anyfoo 5y ago
> Do flu vaccines cause mutations as well? That is not what I have written, please reread!

velcii 5y ago

>But still less than no vaccination.. Can you share why you think the current vaccines will reduce the mutations when we already know that they only prevent symptoms (not even reduce viral load for some variants). So given that, why do you think the current vaccines will reduce the chances for virus to mutate. To me, it appears that the current vaccines will give the exact same chance for the virus to mutate, without the vaccine, but in addition also apply selection pressure to guide the evolution to gain immune escape. So the worst of both worlds.