First.
If people have chosen to get vaccinated, they are not on your side to begin with.
So it is very likely that they are planting fake stories.

Now to the analysis:
Only solid ferromagnetic metals are strong enough to create a strong force.
And you can not put enough of that in an injection.
So they are likely holding magnets under their arm-pits.
One can do something similar with some glue.

But we also have the magnetic boy.
Article
"Just a very sticky kid"
So maybe the vaccine makes you sweat out sticky stuff.