Dr David Martin explains that technically, some of the so-called vaccines for Covid do not legally qualify for the term since they do not operate like a "normal" vaccine (whether that works in UK law or not I'm uncertain):
Towards the end, Judy Mikowitz hits the nail on the head when she says that it works by inserting instructions into your cells to cause them to generate a synthetic pathogen (not a virus) that will prime your immune system to create an immune response to that pathogen.
That's all very well, but nowhere have I heard or seen it explained how your cells are subsequently prompted to turn off the generation of this synthetic pathogen when the immune system has been primed. In my simple mind, your body will continue generating this synthetic pathogen and your immune system will continue to mount its immune response indefinitely, or until it is overwhelmed. One can understand why one of the risks might be an auto-immune problem, but is it more than just a risk - might it not be more of an inevitability?