According
to Advocatehealth.com, PDD occurs in the early years of a child's life.
Children with PDD have difficulty in areas of development or use of
functional skills such as language, communication, social skills, and
motor behaviors. Basically, it's a generic term to classify children
whose development is too prematue to adequately diagnose, such as
Autism, Asperger's Syndrome, Rett's Syndrome, etc. Autism
is a neurological disorder that causes difficulties in verbal and
non-verbal communication, social interactions, and higher functions the
brain.
What causes Autism?
This question continues to elude even the best
scientific minds. According to the Autism Society of America, there is
no known single cause for autism, but it is generally accepted that it
is caused by abnormalities in brain structure or function. Other
theories include the link between heredity, genetics and medical
problems. Other researchers are investigating the possibility that
under certain conditions, a cluster of unstable genes may interfere
with brain development resulting in autism. Still other researchers are
investigating problems during pregnancy or delivery as well as
environmental factors such as viral infections, metabolic imbalances,
and exposure to environmental chemicals.
The really hot theory is a link
to vaccines. Thimerosal is an inorganic mercury compound
that is metabolized to ethylmercury and thiosalicylate and has been
present since the 1930's as a preservative in some vaccines and
pharmaceutical products to prevent bacterial and fungal contamination.
(reference http://www.nationalautismassociation.org/thimerosal.php).
The evidence to link vaccines to autism is growing
each day, with each study, and growing irrefutable data to work with.
It's my personal belief this is the culprit, only time will tell.
