Got my Moderna bivalent booster today. So far, the only effect is a slightly sore shoulder.
If I may vent a little, I went to a local pharmacy that advertises "walk in boosters." Silly me, I thought this suggested at least a hint of "quick" might be involved. It turns out a more complete description would be "walk in, followed by waiting to get a form to fill out, followed by sitting and waiting, followed by more sitting and waiting, followed by more waiting . . ."
I noticed that a couple recent preprints suggested that the bivalent boosters didn't produce a better neutralizing antibody response than the original boosters (both produced a significant immune response).
>>>"There was no significant difference in neutralization of any SARS-CoV-2 variant tested between individuals who received a fourth monovalent vaccine and those who received a fourth dose of a bivalent vaccine," concluded one study
, which has yet to be peer-reviewed, posted by the team led by Ho. . . .
Barouch said a phenomenon called immune imprinting may turn out to be the culprit for the disappointing immune response to the updated booster.
Immune imprinting, also known as "original antigenic sin," refers to the theory that the initial exposure people had to an earlier strain of the virus — either from infection or vaccination — may hinder the ability of the body to produce antibodies to new strains.<<<
Recent small studies, not yet peer-reviewed, suggested the new boosters may not be significantly better than the original vaccine formula.
Apparently the studies also did not show much of a boost in @Swerd
's favorite immune cells:
>>>His team also measured another part of the immune response from T cells. Those were "not substantially" boosted by additional shots from either the bivalent or original formulations.
"We all talk about antibodies, the focus has been on antibodies, but there's two sides to the immune system: antibodies and T cells. And we believe that both are important for protection against severe disease," said Barouch.<<<
I'm curious if further studies confirm that immune imprinting is a significant issue. It looks like it's just a best guess right now that this might explain the results for the bivalent vaccines so far.