I recently posted on selecting the Moderna Covid vax for its larger dose. There is actually a similar choice available for the flu vax.
Flu vax is traditionally made by growing it in chicken eggs, this is why you see warnings about any egg allergies. But this process is slow so they need to guess which flu to grow in the eggs long before we start catching it. Hence they often miss which flu to target.
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A newer type shot is now available in US (~2015) and UK as of last year. It's the brand Flublok and starting in 2022 in US it is recommended for seniors. It does not require eggs and supposedly is signif more effective with fewer adverse effects.I looked for and got this one.
I had near zero side effects, usually I get some from a flu vax. With its claimed better efficacy vs regular vax it's worth considering.
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"The commercial formulation of Flublok contains three times the amount of HA (active ingredient) compared with the standard dose IIVs (egg vaxes) and consequently induces higher antibody titers, which may be of particular importance to those most at risk for influenza (for example, the elderly...or immunologically compromised... "
If you're senior, this new one is really worth considering: "... adverse events in Flublok recipients are generally much less frequent than those observed with Fluzone HD" (HD is the stronger formulation of egg based vax that is required for seniors)
Seems to be good even if the strain changes some: "Importantly, Flublok has demonstrated protective efficacy in a field efficacy trial against drifted influenza viruses"
ncbi.nlm.nih.gov/pmc/articl...
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Image here is from the mfr. (SD-QIV is a regular egg type non-senior flu vax.) It seems a conventional senior high dose vax is similar effective but with more side effects as noted above.