5 ms·

Shouldn't we limit the vaccines for the risk populations in that case? Vaccinating everybody just promotes vaccine resistant variants.

bonzini 5y ago
Not entirely. By reducing the amount of time that the virus spends in your body, it has much less time it has to develop a radically different variant (it has to combine many mutations in order to escape vaccination). Alpha and Omicron at least are theorized to have developed in people that hosted the virus for months.
fer 5y ago
Actually letting the virus mutate without adequate immune response is what produces those variants, as you remove local minima from the evolutionary chain. The fact that most VOCs popped in areas with little to no vaccination coverage quite aligns with that. For omicron the main hypothesis is it actually evolved in a severely immunocompromised HIV patient. Edit: This isn't exactly new[0] and it's also been witnessed for SARS-CoV-2[1]: > These compilations of case reports indicate the need to identify whether certain forms of immunosuppression are associated with an increased risk of such multimutational escape patterns — for instance, specific cancers or specific therapies, such as the development of B-cell aplasia related to CAR T-cell or anti-CD20 therapy, prolonged use of glucocorticoids, long-term chemotherapy, or radiotherapy. Similarly, organ transplant recipients and those with untreated or poorly controlled human immunodeficiency virus infection may also have prolonged SARS-CoV-2 infection and could constitute a reservoir of divergent escape variants that can spread in the general community. Prolonged viral replication in the context of an inadequate immune response facilitates the emergence of immune-pressure escape mutations.[0] I'd appreciate an actual counter argument, other than a poorly understood Marek disease analogy. [0]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4249157/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4249157/ [1]https://www.nejm.org/doi/full/10.1056/NEJMsb2104756 https://www.nejm.org/doi/full/10.1056/NEJMsb2104756
- deleted 5y ago
  [deleted]
- moistly 5y ago
  I’d appreciate an actual counter argument, too, because all I see here is that anti-vax twits are downvoting facts.
yyyk 5y ago
All the concerning mutations we keep hearing about arose in overwhelmingly unvaccinated populations*. Alpha in Britain before it widely vaxed. Beta in South Africa. Gamma in South America. Delta in India. And now this in Africa again. If we want to keep the occurrence down, we need to vax as much of the world as we can. * Hiding this fact is a serious problem of the 'never name a mutation by a place' new WHO policy.
- deleted 5y ago
  [deleted]
- incrudible 5y ago
  It's true that South Africa is largely unvaccinated, but seroprevalence is over 70%, making it one of the most immunized places on earth. Delta had little room to grow, so whatever came next had to be a mutation with some immune-escape properties. Considering that even the most highly vaccinated places on earth are shattering records of infection rates, it seems implausible that vaccinating the rest of the world would somehow fix this issue. The "most unvaccinated" places on earth are also some of the most populous, therefore a variant is most likely to arise there out of pure chance. In this case, due to the large number of mutations, the prime suspect is an untreated HIV patient with a lingering infection, which is most likely to happen in the southern parts of Africa. It's not clear whether vaccines prevent lingering infection in such a case.
  - yyyk 5y ago
    >It's true that South Africa is largely unvaccinated, but seroprevalence is over 70%, making it one of the most immunized places on earth. OP was suggesting intentionally limiting vaccination. If 'natural' immunity can also allow for antibody-evading mutations, than we get nothing from limiting vaccinations - my point exactly. >Considering that even the most highly vaccinated places on earth are shattering records of infection rates, it seems implausible that vaccinating the rest of the world would somehow fix this issue. We cannot make mutation never happen, but we can limit the damage by vaccinating more. This will help us gain time to get more effective medications.
dtech 5y ago
The added transmission, overall prevalence, and longer and more severe resulting sicknesses make mutation more likely in un-vaccinated populations by several order of magnitude.
podgaj 5y ago
If we want SASR2 to mutate into a less deadly version than we need to let it spread SAFELY. This is done through vaccines and NOT wearing masks. It can be accomplished as you said, but there is just more risk to life. SARS2 mutates much more slowly than Influenza so, IMO, we actually NEED to get people more infected. I would not be saying this if we locked every country down in the beginning but this is where we are.
tzs 5y ago
With mRNA vaccines shouldn't it be possible to quickly adapt the vaccine to those variants? I'd expect they only have to change the mRNA to code for the spike protein of the variant, leaving everything else in the vaccine the same. That should mean that the potential side effects should be the same and with the same frequency, which should greatly reduce the amount of safety testing needed to ensure that it is as safe as its predecessors.
- angelzen 5y ago
  We don't know. They can change the mRNA code for the new spike protein, but they can't force the immune system to respond to the new code. For all we know, the immune system may mistakenly generate a response for the spike it was first imprinted against. This is a well known and documented phenomenon called "original antigenic sin". It sucks. https://www.jstor.org/stable/985534 https://www.jstor.org/stable/985534 https://pubmed.ncbi.nlm.nih.gov/28479213 https://pubmed.ncbi.nlm.nih.gov/28479213

bonzini 5y ago

Not entirely. By reducing the amount of time that the virus spends in your body, it has much less time it has to develop a radically different variant (it has to combine many mutations in order to escape vaccination). Alpha and Omicron at least are theorized to have developed in people that hosted the virus for months.

fer 5y ago

Actually letting the virus mutate without adequate immune response is what produces those variants, as you remove local minima from the evolutionary chain. The fact that most VOCs popped in areas with little to no vaccination coverage quite aligns with that. For omicron the main hypothesis is it actually evolved in a severely immunocompromised HIV patient. Edit: This isn't exactly new[0] and it's also been witnessed for SARS-CoV-2[1]: > These compilations of case reports indicate the need to identify whether certain forms of immunosuppression are associated with an increased risk of such multimutational escape patterns — for instance, specific cancers or specific therapies, such as the development of B-cell aplasia related to CAR T-cell or anti-CD20 therapy, prolonged use of glucocorticoids, long-term chemotherapy, or radiotherapy. Similarly, organ transplant recipients and those with untreated or poorly controlled human immunodeficiency virus infection may also have prolonged SARS-CoV-2 infection and could constitute a reservoir of divergent escape variants that can spread in the general community. Prolonged viral replication in the context of an inadequate immune response facilitates the emergence of immune-pressure escape mutations.[0] I'd appreciate an actual counter argument, other than a poorly understood Marek disease analogy. [0]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4249157/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4249157/ [1]https://www.nejm.org/doi/full/10.1056/NEJMsb2104756 https://www.nejm.org/doi/full/10.1056/NEJMsb2104756

deleted 5y ago
[deleted]
moistly 5y ago
I’d appreciate an actual counter argument, too, because all I see here is that anti-vax twits are downvoting facts.

yyyk 5y ago

All the concerning mutations we keep hearing about arose in overwhelmingly unvaccinated populations*. Alpha in Britain before it widely vaxed. Beta in South Africa. Gamma in South America. Delta in India. And now this in Africa again. If we want to keep the occurrence down, we need to vax as much of the world as we can. * Hiding this fact is a serious problem of the 'never name a mutation by a place' new WHO policy.

deleted 5y ago
[deleted]
incrudible 5y ago
It's true that South Africa is largely unvaccinated, but seroprevalence is over 70%, making it one of the most immunized places on earth. Delta had little room to grow, so whatever came next had to be a mutation with some immune-escape properties. Considering that even the most highly vaccinated places on earth are shattering records of infection rates, it seems implausible that vaccinating the rest of the world would somehow fix this issue. The "most unvaccinated" places on earth are also some of the most populous, therefore a variant is most likely to arise there out of pure chance. In this case, due to the large number of mutations, the prime suspect is an untreated HIV patient with a lingering infection, which is most likely to happen in the southern parts of Africa. It's not clear whether vaccines prevent lingering infection in such a case.
- yyyk 5y ago
  >It's true that South Africa is largely unvaccinated, but seroprevalence is over 70%, making it one of the most immunized places on earth. OP was suggesting intentionally limiting vaccination. If 'natural' immunity can also allow for antibody-evading mutations, than we get nothing from limiting vaccinations - my point exactly. >Considering that even the most highly vaccinated places on earth are shattering records of infection rates, it seems implausible that vaccinating the rest of the world would somehow fix this issue. We cannot make mutation never happen, but we can limit the damage by vaccinating more. This will help us gain time to get more effective medications.

dtech 5y ago

The added transmission, overall prevalence, and longer and more severe resulting sicknesses make mutation more likely in un-vaccinated populations by several order of magnitude.

podgaj 5y ago

If we want SASR2 to mutate into a less deadly version than we need to let it spread SAFELY. This is done through vaccines and NOT wearing masks. It can be accomplished as you said, but there is just more risk to life. SARS2 mutates much more slowly than Influenza so, IMO, we actually NEED to get people more infected. I would not be saying this if we locked every country down in the beginning but this is where we are.

tzs 5y ago

With mRNA vaccines shouldn't it be possible to quickly adapt the vaccine to those variants? I'd expect they only have to change the mRNA to code for the spike protein of the variant, leaving everything else in the vaccine the same. That should mean that the potential side effects should be the same and with the same frequency, which should greatly reduce the amount of safety testing needed to ensure that it is as safe as its predecessors.

angelzen 5y ago
We don't know. They can change the mRNA code for the new spike protein, but they can't force the immune system to respond to the new code. For all we know, the immune system may mistakenly generate a response for the spike it was first imprinted against. This is a well known and documented phenomenon called "original antigenic sin". It sucks. https://www.jstor.org/stable/985534 https://www.jstor.org/stable/985534 https://pubmed.ncbi.nlm.nih.gov/28479213 https://pubmed.ncbi.nlm.nih.gov/28479213