"I don't trust this vaccine, but I trust this other vaccine."
Are we really going through this?
Don't worry, it's part of the origin story for anti vax rhetoric...
Oh right, it's not that commonly known.
Andrew Wakefield is the piece of crap we have to blame for this. The short of it is, he wanted to sell his own vaccine back in the UK, for profit. So he created a scare, using a small group of children who had autism. And claimed that the MMR vaccine in specific, when combined caused autism. Media picked up on the story, but didn't really look into it, resulting in this situation spreading.
We're going to skip past that this paper was retracted, because not only was the science bad, but Wakefield literally created his own data. Which is also why he declined to get a bigger sample size.
As for what he lied about. He lied about some of the children having autism some of the kids were perfectly healthy and had no bowl issues (he claimed that was the sign of it.)
The science was also bad because he was asking parents
when they thought the kid started having signs of autism. Which as people might know, human memory is pretty poor, and we often miss or forget things, or incorrectly associate things because monkey brain. And he even lied about the data regarding what times the parents noticed it, because why the fuck not at this point if your going to outright lie. Oh he also lost his license too
Oh, and what was this all for??? So he could sell each part of the vaccine, separately, for profit. As the MMR vaccine was government funded.
Oh by the way he shows up at anti vaxx meet ups in the states, and of course he changed his tune to say that all vaccines are bad.
Oh I also forgot to mention, the disgraced former doctor he partnered up with (abusing drugs, lost his medical license over it) believed that his bone marrow could cure autism..... YUP.
Edit: if you want more information on all of this, check hbomberguy's video about vaccines. If you don't want to watch it, because of his humor sucking or something. Check the description, as he has a google doc including all of his sources.