It may be cause and effect, but it may also be that the vaccine (or its adjutant) present a challenge to our immune systems—and its our immune systems that are the problem. There’s a difference between an associated reaction in some people and a 1:1 correlation for all people. I think we have to be careful here and not jump to conclusions. I don’t want COVID or the flu, pneumonia, or shingles so I take the shots. But I’m also aware that my immune system is wonky (a scientific term for sure) and my body over-reacts to a lot of things! Chiggers, for example. Animal dander. IVP fluid. I am interested in learning how to calm down my immune response.