Autism is a genetic disorder; present before birth. It is associated with older fathers as the number one risk factor. It is so super genetic, much more so than other conditions. If one identical twin is diagnosed, there is a 90% chance of the other twin having the same disorder.
People use inductive reasoning and go: “well Johnny had his vaccines and was diagnosed with autism at the same time. Therefore the vaccine did it”
But they do so without understanding the underlying science of both vaccines and autism.
The reason they appear to occur at the same time: 1) vaccines are given at the earliest safe interval.(ie 2) 2) rapid myelination occurs at this time (ages 2 and 5 respectively). Rapid myelination is basically growth of brain tissue. 3) you start with a crappy genetic copy, and then make more of said crappy genetic copy present in each cell of brain tissue= obvious autism. 4) this means that at ages 2 and 5 autism symptoms are more present. They were already there, but most lay people cannot tell autism in infants. (That and there are conditions that can mimic autism — intellectual disabilities, adhd, etc. those are very difficult to tease out that early.)
Other factors that may color parent’s understanding or may be mistaken as an autism dx:
A) misdiagnosis, and apple/tree situations. Many people before the 90s were misdiagnosed as being either intellectual disabled, learning disordered, or having ADHD. The parent actually has autism and not one of the former diagnoses. If a parent already has autism it is very likely his/her child will have it too.
B) severe coddling, helicopter parenting. Not allowing your child to mature socially or to not allow problem solve issues by themselves leaves them unable to do so as they grow up. If mom and dad are always solving arguments for them or speaking for their child once again will cause social delays. This is not autism, and would not qualify for the diagnosis (dx), although many schools will qualify them anyway. You can’t have Johnny running around as an adult thinking mommy can solve his problems for him, or Johnny doesn’t know to ask friends for help.
C) parent has a significant mental illness, untreated or not responding to medication well enough (partially recovered).
You are your child’s earliest role model. If Johnny sees dad getting anxious about meeting new people at work or anxious about leaving the house, Johnny will have the same problem. Once again this is not autism, but the child may demonstrate s/s (signs and symptoms) of his or her parents mental illness.
Sources:ASHA conducted research, and my neuropathologies textbook, which quotes research like it’s pizza day at a high school. I’m too lazy to find the the book in my house at the moment. God knows where it is.