Autism is no longer considered a rare disorder. The Center for Disease Control (CDC) and Prevention’s Autism and Developmental Disabilities Monitoring Network released data in 2007 that found about 1 in 150 8-year-old children in multiple areas of the United States had an autism spectrum disorder (ASD). Although currently there is not a full population count of all individuals with an ASD in the United States, the CDC estimates that up to 560,000 individuals between the ages of 0 to 21 years have an ASD.

In 2006, 224,594 children ages 6-21 and 35,111 children ages 3-5 were served under the “autism” classification for special education services. These numbers are believed to be an underestimation of the prevalence of autism because some children with autism spectrum disorders are categorized under a different IDEA disability category, others may have been misclassified and others have yet to be diagnosed.

Currently, diagnosis of autism is based solely on observation of behaviors detailed in the Diagnostic and Statistical Manual of Mental Disorders-IV-TR (2000). Because symptoms vary considerably from individual to individual, diagnosis can be quite difficult. In the Diagnostic and Statistical Manual of Mental Disorders-IV-TR (2000), autism falls under the clinical categorization of Pervasive Developmental Disorders. Other autism spectrum disorders which fall under the same umbrella category are Asperger Syndrome, Childhood Disintegrative Disorder, Rett Syndrome, and Pervasive Developmental Disorder: Not Otherwise Specified (PDD-NOS).

According to the Diagnostic and Statistical Manual of Mental Disorders - IV-TR (2000), individuals with autism can, although do not always, exhibit the following behaviors: difficulty using nonverbal behaviors for social purposes, difficulty developing appropriate peer relationships, lack of social/emotional reciprocity, difficulty in development of spoken language, impairment in sustaining conversation with others, stereotyped and repetitive use of language, lack of spontaneous social play, abnormal preoccupation with patterns of interest, inflexible adherence to routines, repetitive motor behaviors, and preoccupation with objects.

Individuals with autism will vary tremendously in the type of, number of, and severity of symptoms that they present, and in the type of other medical conditions and challenges that they have. Additionally, because it is a developmental disability, autism may affect an individual differently at different stages of their lifespan.

References

American Psychiatric Association, Taskforce on DSM-IV (2000). Diagnostic and Statistical Manual of Mental Disorders IV-TR. Washington, DC: American Psychiatric Association.

Centers for Disease Control and Prevention (2008). Prevalence of ASDs. Retrieved August 20, 2009, from Center for Disease Control and Prevention: Autism Information Center Website: http://www.cdc.gov/ncbddd/autism/faq_prevalence.htm