If autism was something we had genetic or biological tests for, this would be a valid concern. Presently, however, we don't have a biomarker for autism - the studies determine whether children have autism by looking at their symptoms. If vaccines did cause a significant increase in symptoms, we should expect it to move some number of individuals from "undetectable" to "detectable" and we'd see that in the numbers.
There is the narrow possibility, which may well have been looked at but hasn't been discussed, that vaccines could make autism worse only when it is significant to begin with, so nothing is crossing the threshold between not-quite-autism to autism, but I don't think we have any more evidence cause us to expect that relative to the simpler hypothesis that vaccines have roughly the same impact at any degree of autism: none.
Thank you for being the only one to understand my point (which you pointed out in your second paragraph) and not just knee-jerk down voting. My account was automatically censored by the HN algorithm for exploring a controversial viewpoint.
As for the bio-marker there are a number of things that could be looked at: flue/bascterial infection during pregnancy, age of father, anti bodies in mother, rheumatoid arthritis genetic markers in mother, asthma markers.
I have to disagree that it is a narrow possibility. So much of the future of a child is determined during the formative years. Intentionally aggravating an at-risk child's immune system over and over again is something that needs to be very closely researched. To not do so at this point given all that we know seems very unethical.
There is the narrow possibility, which may well have been looked at but hasn't been discussed, that vaccines could make autism worse only when it is significant to begin with, so nothing is crossing the threshold between not-quite-autism to autism, but I don't think we have any more evidence cause us to expect that relative to the simpler hypothesis that vaccines have roughly the same impact at any degree of autism: none.