One of the many problems with science denial is figuring out where the rumors started.
In terms of the war on vaccination, Science has nicely provided a list of claims and where they originated. Read it here.
Also as a bonus, see this pediatrician’s response to parents that don’t want to vaccinate their children. His post has recently gone viral (even though it’s been around for awhile), and is worth reading. He especially emphasizes that he is willing to answer every question that parents have about vaccines, but he’s just not willing to make exceptions.