There is currently no known cause of autism or autistic spectrum disorders. ASD is a neuro-developmental
disorder. Over the past two decades, the rate of autism has increased from 3.3 cases in 10,000 in the 1980's to
between 55-70 cases per 10,000 recently (or 1 in 200 births for autism and 1 in 400 births for Asperger's Syndrome). Consequently
a lot of research dollars have been provided in an attempt to explain this dramatic increase in ASD cases.
First it was thought that the increase merely represented better and earlier diagnosis. Symptoms
such as poor social skills, poor communication skills, disrupted joint attention, delayed theory-of-mind, non-functional
play behaviour, and repetitive or ritualistic patterns of behaviour become more obvious around the child's third birthday,
especially when parents begin to compare their child with other "typically developing" children of the same age. We
now have reliable assessment tools able to screen for autistic spectrum disorders in eighteen month to two year old children.
Some parents have remained adament that their child was developing "typically" until they were vaccinated
for measles, mumps, and rubella, at which time their language seemed to "regress" and reciprocal social play skills "diminished".
The following articles relate to two streams of controversial research in this area which suggests 1) that environmental
exposure to heavy metals (including the preservative used in vaccines), and 2) a deficiency in enzymes in the stomach
may be contributing to the development of autism.
