@DrEricDing @VirusesImmunity @PeterHotez This is a great question
The vaccine is not necessarily a more trusted source of immunity. Both an infection AND a vaccine are likely to induce good immune responses. All of the information we have suggests that immunity to infection for this virus is... well... as expected
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The vaccine is not necessarily a more trusted source of immunity. Both an infection AND a vaccine are likely to induce good immune responses. All of the information we have suggests that immunity to infection for this virus is... well... as expected
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@DrEricDing @VirusesImmunity @PeterHotez However, to the questioners point, we are hoping the vaccines will induce potent and long lasting immunity. The vaccines are designed specifically to direct our immune response to look in the right spot - vs searching all over the virus...
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@DrEricDing @VirusesImmunity @PeterHotez The leading vaccines are all designed to induce, primarily, an antibody response that specifically blocks virus entry. To do this, they display a piece of the spike protein - the key to unlock entry into the cell.
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@DrEricDing @VirusesImmunity @PeterHotez If the immune system learns just one thing well - and that is to create an antibody that blocks the key from being used... well that’s a massive win. It’s the type of response that is really ideal - prevent infection in first place rather than clean it up when it happens.
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@DrEricDing @VirusesImmunity @PeterHotez We call this type of immunity sterility. Or slightly different but similar, neutralizing. It neutralizes the virus upon entry so it can not bind.
Ok. But why am I talking about all of this when your question was about vaccine vs infections...
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Ok. But why am I talking about all of this when your question was about vaccine vs infections...
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@DrEricDing @VirusesImmunity @PeterHotez When you get a natural infection, the immune system has a bit more of a “choose your own adventure” to deal with.
So many different knobs and handles and other things on the virus to potentially recognize and memorize.
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So many different knobs and handles and other things on the virus to potentially recognize and memorize.
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@DrEricDing @VirusesImmunity @PeterHotez Some of these proteins and virus bits will be very immunogenic but maybe not the most useful to recognize - like forming an antibody to someone’s pinky toe. Just not that useful. And others like an antibody to the receptor binding domain are very useful.
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@DrEricDing @VirusesImmunity @PeterHotez All different people have slightly different responses. So an immune memory formed from a natural infection may or may not be all that useful.
But at the same time, w a natural infection, you have opportunity to form LOTS of new distinct memories, which can prove beneficial.
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But at the same time, w a natural infection, you have opportunity to form LOTS of new distinct memories, which can prove beneficial.
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@DrEricDing @VirusesImmunity @PeterHotez Some of the new memories will be remembered by antibodies and be useful. Some not as much (though new research shows that even non-neutralizing antibodies are crucial)
Importantly T cells work very differently from antibodies. Recognizing a pinky toe may be very beneficial!
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Importantly T cells work very differently from antibodies. Recognizing a pinky toe may be very beneficial!
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@DrEricDing @VirusesImmunity @PeterHotez Essentially if you can induce a good T cell response and it remembers a part of the virus well (an epitope) then it can prove v useful
The vaccines were not designed for this purpose (induce T cell memory) as much as their focus on a neutralizing antibody response.
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The vaccines were not designed for this purpose (induce T cell memory) as much as their focus on a neutralizing antibody response.
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@DrEricDing @VirusesImmunity @PeterHotez But that said They appear to be inducing T cell responses AND antibody responses which is.
There is some precedent too for a narrow response (ie directed at spike only) to be potentially better than a broad response induced by infection...
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There is some precedent too for a narrow response (ie directed at spike only) to be potentially better than a broad response induced by infection...
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@DrEricDing @VirusesImmunity @PeterHotez HPV vaccines, despite being narrow targeted vaccines tend to perform better than natural infection to induce robust lasting and cross reactive immunity.
Why, is under investigation.
Additionally, vaccines can be tuned to induce the best response possible!
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Why, is under investigation.
Additionally, vaccines can be tuned to induce the best response possible!
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@DrEricDing @VirusesImmunity @PeterHotez So much of “locking in” good memory responses is about boosting. This happens naturally w Re-exposures (yes reinfections are not necessarily bad - just like training... repetition is good)
Vaccines can be calibrated appropriately for this - not exactly science but improving
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Vaccines can be calibrated appropriately for this - not exactly science but improving
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@DrEricDing @VirusesImmunity @PeterHotez So, to conclude, vaccines can be calibrated and targeted for maximal immune response FOR THAT PROTEIN.
But the downfall is it’s a narrow vaccine. Mutations can more easily enable immune escape (none identified yet!). Diversity in responses can be helpful.
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But the downfall is it’s a narrow vaccine. Mutations can more easily enable immune escape (none identified yet!). Diversity in responses can be helpful.
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@DrEricDing @VirusesImmunity @PeterHotez In this case though, most beneficial is getting a vaccine to drive immune memory instead of an infection. All signs suggest it should work fairly well, if not excellent?
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