Read The article at http://www.usatoday.com/news/health/2009-10-05-autism-increase_N.htm

Autism is more widespread, U.S. studies show, but why?   Posted 10/5/2009 12:01 AM


says--
Two new government studies suggest autism spectrum disorders are becoming more common in children in the USA. However, researchers say, it is not clear how much of the increase is a result of more frequent and earlier diagnoses and how much is a result of a real rise in the conditions.

One of the studies, published today in the journal Pediatrics by researchers at the Health Resources and Services Administration, found that one in every 91 children ages 3 to 17 have such a disorder, as determined by a survey of the parents of 78,000 children. That's an estimated 673,000 children, the authors write. In half the cases, parents report their children's symptoms as "mild."