Can you provide examples? The only example of a 'scientific' study I am aware of is the disgraced Wakefield stuff which has been disproven so many times it isn't even funny. That's before you add in the malpractice that happened and the conflict of interest he held.

Some people have an allergic reaction. (probably 1 in a million). That is a scientific fact, and enough for them to get a lot of mileage.

I have not looked into any of this, so I tend to think it’s probably bunk since authorities dismiss it as such. Many others, it would seem, do not dismiss it. http://adventuresinautism.blogspot.com/2007/06/no-evidence-o...

Italian researchers tested 44 different vaccines and found significant contamination in all of them, ranging from red blood cells to lead, tungsten, gold, and chromium.

The describe this finding as "baffling" and call for better purification and quality control, given that many of the contaminants were capable of causing health problems.

"New Quality-Control Investigations on Vaccines: Micro- and Nanocontamination"

https://medcraveonline.com/IJVV/IJVV-04-00072.pdf

Someone said, that Merck is being sued for constructing evidence in vaccination fraud or something.