The link between the syndrome we were seeing and MMR vaccine came from the parental story. The parents saying, “I wasn’t anti-vaccine. I took my child to be vaccinated with MMR on time.” It was given in isolation at the time in the UK, so it was easy for them to pinpoint the MMR as what they believed to be the cause. From that point forward, their child developed a very high fever, seizures, prolonged sleep beyond which they woke up and they were never the same again. They lost speech and language, interaction with their siblings, and became profoundly unwell.
The way in which human disease, syndromes, are described, whether it’s autism, or Crohn’s Disease or Asperger’s, is you have a collection of a few, a handful of patients, sometimes no more than four, sometimes as many as fifteen, where the presentation is so similar, the findings in the clinic are so similar, that these merit publication in their own right. That’s called a case series. That is the way in which human disease syndromes are first described. What that leads to are subsequent studies, which then test hypothesis of causation. Was the parent’s stories right? Was it that the child did regress in the face of MMR, and was MMR the cause of the problem?
You can ask the question, “Well, not every child who gets MMR develops autism, so what is the risk?” Why? Why these children and not these children? One of our hypothesis was age of exposure. The younger you get the vaccine, the greater the risk. The reason for putting that forward is that we know with infections like measles, the younger you get measles, the greater the risk of a serious outcome. If you get measles under one, the risk of serious disease following measles is much greater than if you get it over one.
— Andrew Wakefield, MD