How strong is the evidence refuting the autism myth?

In an episode of the MAHA podcast, pediatrician Joel Warsh claims that vaccine safety research is weak because it hasn’t compared vaccinated to unvaccinated children or studied all vaccines together.

https://pmc.ncbi.nlm.nih.gov/articles/PMC2908388/

Anti-vaxxers exploit how exact science can be when talking about autism. Science cannot prove that something doesn’t happen. We can’t prove that unicorns don’t exist; we can only point out that no credible sighting of a unicorn has ever taken place and that we do not have evidence like unicorn scat or unicorn fossils to support the hypothesis that unicorns exist.

So science cannot say that vaccines absolutely do not cause autism, only that no credible evidence exists to show that it does cause autism. But this isn’t a scientific paper, and we all know that vaccines do not cause autism.

In 1998, when Wakefield held the press conference about his fraudulent and now retracted paper, we didn’t know as much about autism as we do today.  Studies show that autism is mostly genetic and often starts before birth, during early brain development in the womb. The brain differences seen in autism are usually there before birth and don’t appear suddenly because of things like vaccines. This supports research suggesting that autism’s main causes happen well before a baby is born.

Large-scale studies from global health authorities, including the CDC, WHO, and various peer-reviewed sources, have repeatedly shown no causal link between vaccines and autism. One notable study from Denmark looked at more than 650,000 children born between 1999 and 2010 to see if the measles‑mumps‑rubella (MMR) shot could be linked to autism. They followed each child for years and counted about 6,500 autism diagnoses, but kids who got the MMR shot were no more likely to develop autism than kids who skipped it. There’s your vaccinated-versus-unvaccinated study.

Why don’t anti-vaxxers accept these studies? The reasons are many, but mostly because they aren’t ready to do so. And so they simply move away from “The MMR causes autism” to “Too many vaccines cause autism” or “This other vaccine causes autism.” The cycle is never-ending, and we could use those research dollars instead to find ways to make the lives of autistic people better.