Although I'm not a researcher/scientist/medical professional I'm not convinced that vaccinations are a cause of OMA. I did a lot of medical literature reviews on OMA when my daughter was first diagnosed. From my research there were several studies done on the anatomy of the brain of kids with OMA. Imaging studies such as MRIs and CT scans where taken. A majority of the time they found abnormalities to some part of the brain, I want to say the size of the ventricles or something but I can't remember for sure, it's been some time ago. This leads me to belive that this would occur gradually over time, such as during development in the womb, rather than acutely, such as following a vaccination. Other than not tracking and not looking at our faces (which I had no idea was not normal until she was 2 months old), my daughter didn't have any health problems after birth and she received all the standard vaccinations.
From all of my research I have found it's a genetic disorder. I don't know of any family members on either my husbands or my side of the family who have had it but then again OMA was only discovered relatively recently and could have gone undiagnosed. More support for genetics as the cause are those who have posted on this website as having more than one child with OMA or having OMA themselves with a child who has OMA.
Although I responded to this topic of discussion I really haven't thought about it for quite some time. My 19 month old daughter has OMA. She is gross motor delayed so she's getting physical therapy. She's as smart as a whip, very social, has a great tempermant, and is just a wonderful child (if I do say so myself :)). It serves no purpose for me at this point to "worry" about it. I'm dealing with the here and now and with her future. I'm not concerned about the past.
Certainly it's not a bad idea to raise questions in the hopes that you will raise awareness. But for me it's not worth wondering why anymore. Best of luck to all of you in search of more answers. I hope you find what you are looking for.