The apparent paucity of vaccine-associated myocarditis cases among the 5-11 age group is really interesting. It also seems clear now, based on data presented to VRBPAC and ACIP (among other sources), that:
- The reaction is most common in males in their late teens and early 20s.
- It does occur following the first dose in a significant number of cases (though far less frequently than following the second).
- It's occurring less frequently with third doses, though that could just be due to selection bias.
- It seems to be somewhat more common with the Moderna vaccine than with the Pfizer vaccine.
I wonder if, taken together, this information can tell us anything about the underlying mechanism of mRNA vaccine-induced myocarditis?
Point 1 is of course vital information but I don't think speaks to mechanism, or at least not in a way that's meaningful for me.
Point 2 I think is evidence that this is kind of a crapshoot, or that some amount of inflammatory load is required to get to this. It's also hard to read into because the case numbers for this event are pretty small.
Point 3...as you say. Hard to rely on that so far.
Point 4 tells us potentially that this is a dose-dependent effect. That's interesting on its own, and I think the most likely explanation.
But all we can really learn from that is that the effect, when it occurs, is probably a direct reaction to the vaccine rather than some sort of cascade that the vaccine kicks off but which then self-reinforces. Otherwise I would expect the context where it occurs to be more random. Point 2 may also speak to this; giving two doses in quick succession may provide enough dosage on average for some people to pass a threshold for inflammation and get myocarditis.
We still don't know, though, what makes it happen in the certain people where it happens. That's hard to assess.
I wonder, though, if this might be another situation where a longer dosing schedule could help. I also still think accidental intravenous delivery may be involved, or a contributing factor to at least some of the frequency.
The apparent paucity of vaccine-associated myocarditis cases among the 5-11 age group is really interesting. It also seems clear now, based on data presented to VRBPAC and ACIP (among other sources), that:
- The reaction is most common in males in their late teens and early 20s.
- It does occur following the first dose in a significant number of cases (though far less frequently than following the second).
- It's occurring less frequently with third doses, though that could just be due to selection bias.
- It seems to be somewhat more common with the Moderna vaccine than with the Pfizer vaccine.
I wonder if, taken together, this information can tell us anything about the underlying mechanism of mRNA vaccine-induced myocarditis?
The last point is the most informative, IMO.
Point 1 is of course vital information but I don't think speaks to mechanism, or at least not in a way that's meaningful for me.
Point 2 I think is evidence that this is kind of a crapshoot, or that some amount of inflammatory load is required to get to this. It's also hard to read into because the case numbers for this event are pretty small.
Point 3...as you say. Hard to rely on that so far.
Point 4 tells us potentially that this is a dose-dependent effect. That's interesting on its own, and I think the most likely explanation.
But all we can really learn from that is that the effect, when it occurs, is probably a direct reaction to the vaccine rather than some sort of cascade that the vaccine kicks off but which then self-reinforces. Otherwise I would expect the context where it occurs to be more random. Point 2 may also speak to this; giving two doses in quick succession may provide enough dosage on average for some people to pass a threshold for inflammation and get myocarditis.
We still don't know, though, what makes it happen in the certain people where it happens. That's hard to assess.
I wonder, though, if this might be another situation where a longer dosing schedule could help. I also still think accidental intravenous delivery may be involved, or a contributing factor to at least some of the frequency.
It's hard to say for certain.