What about getting j&j as the booster if you had mRNA the first time around? I got my two does if Pfizer, and my 6 months just hit, so looking at what to get for a booster. Realistically, I'll get whatever is offered, but if I have options, I might as well make a choice.
I haven't looked into it in detail (there are some good references and comments in this thread), but as a matter of common sense to me, it always felt like a mix-and-match should be better for the booster. If the vaccines target slightly different physical features of the virus, then the resulting antibodies should likewise target slightly different physical features. Seems to me like that would give better protection overall. (In other words, if virus parts A and B are targeted by the vaccines and antibodies produced to each, then if part A mutates, resulting less effective antibody response to A, then part B is still being targeted by the original B antibodies.)
holterskolter2 wrote:
What about getting j&j as the booster if you had mRNA the first time around? I got my two does if Pfizer, and my 6 months just hit, so looking at what to get for a booster. Realistically, I'll get whatever is offered, but if I have options, I might as well make a choice.
The study embedded by Harambe above doesn’t say it in the text, but it shows the antibody levels in the last figure.
Page 27, the last Figure, in “B” and “E”, shows the bar of neutralizing antibodies, after a J&J booster, against the two most recent variants. The first bar is when both inoculations were with J&J, the second bar is Moderna then J&J booster, the third is Pfizer then J&J booster.
If you compare the bars to the figure “A” and “D” where the booster is Moderna, or “C” and “F” where the booster is Pfizer, you can basically see that the responses are identical.
So if you got vaccinated with Moderna or Pfizer, any of the 3 booster regimens I’ll give an identical response.
PCRF-Guy and Harambe summed it up the current state of knowledge pretty well,... which is that there's no clear evidence to base that call on yet.
It became clear to me back around Labor Day that a booster was a good idea (I was already approaching 6 months out then), and that it was stupid to wait for the CDC/FDA to get around to formally 'approving' it, when it was obvious they'd end up doing it within a couple of months anyway.
I spent a couple of weeks looking for an answer on exactly the Q you're asking, and couldn't find one anywhere, so I went for the safe/easy 'default' route --which was to just stick with Pfizer.
It might turn out that switching to Moderna is better, but we just don't know yet.
Good thing is that the latest data on the benefit of a third Pfizer is *very* encouraging --indicating you're something like 20 times less likely to get sick after your third (at least in the time-frame they've been able to assess thus far) than without your third.
FWIW, neither I nor the two friends I took with me experienced any major side-effects from number 3. (I had a day and a half of serious fatigue from #2, very little from #3.)
P.S. I agree with the sentiment that it seems likely in general common-sense terms that a switch-up might offer better protection --and there was some evidence that seemed to be the case for the choice of a second shot.
But there isn't any clear evidence yet that that hold true for a third shot, and so far the best evidence we've got so far on anything about boosters is that a third Pfizer seems to be working very well.