Autism is a brain development disorder that impairs social interaction and communication, and causes restricted and repetitive behavior, all starting before a child is three years old. This set of signs distinguishes autism from milder autism spectrum disorders (ASD) such as Asperger syndrome.^[1]

Autism is highly heritable, although the genetics of autism are complex and it is generally unclear which genes are responsible.^[2] In rare cases, autism is strongly associated with agents that cause birth defects.^[3] Other proposed causes, such as childhood vaccines, are controversial and the vaccine hypotheses lack convincing scientific evidence.^[4] Most recent reviews estimate a prevalence of one to two cases per 1,000 people for autism, and about six per 1,000 for ASD, with ASD averaging a 4.3:1 male-to-female ratio. The number of people known to have autism has increased dramatically since the 1980s, at least partly due to changes in diagnostic practice; the question of whether actual prevalence has increased is unresolved.^[5]

Autism affects many parts of the brain; how this occurs is poorly understood. Parents usually notice signs in the first two years of their child's life. Early behavioral or cognitive intervention can help children gain self-care, social, and communication skills. There is no cure.^[6] Few children with autism live independently after reaching adulthood, but some become successful,^[7] and an autistic culture has developed, with some seeking a cure and others believing that autism is a condition rather than a disorder.^[8]

Autism is a complex developmental disability that typically appears during the first three years of life and affects a persons ability to communicate and interact with others. Autism is defined by a certain set of behaviors and is a "spectrum disorder" that affects individuals differently and to varying degrees. There is no known single cause for autism, but increased awareness and funding can help families today.

In February 2007, the Centers for Disease Control and Prevention issued their ADDME autism prevalence report. The report, which looked at a sample of 8 year olds in 2000 and 2002, concluded that the prevalence of autism had risen to 1 in every 150 American children, and almost 1 in 94 boys. The issuance of this report caused a media uproar, but the news was not a surprise to ASA or to the 1.5 million Americans living with the effects of autism spectrum disorder. Nonetheless, the spotlight shown on autism as a result of the prevalence increase opens opportunities for the nation to consider how to serve these families facing a lifetime of supports for their children.

Currently, ASA estimates that the lifetime cost of caring for a child with autism ranges from $3.5 million to $5 million, and that the United States is facing almost $90 billion annually in costs for autism (this figure includes research, insurance costs and non-covered expenses, Medicaid waivers for autism, educational spending, housing, transportation, employment, in addition to related therapeutic services and caregiver costs).

Know the Signs: Early Identification Can Change Lives

Autism is treatable. Children do not "outgrow" autism, but studies show that early diagnosis and intervention lead to significantly improved outcomes.

Here are some signs to look for in the children in your life:

• Lack of or delay in spoken language
• Repetitive use of language and/or motor mannerisms (e.g., hand-flapping, twirling objects)
• Little or no eye contact
• Lack of interest in peer relationships
• Lack of spontaneous or make-believe play
• Persistent fixation on parts of objects

Last updated: 21 January 2008