What is Autism?

Autism Spectrum Disorder (ASD) or simply Autism refers to a group of complex neurodevelopment disorders characterized by repetitive and characteristic patterns of behavior and difficulties with social communication and interaction. The symptoms are present from early childhood and affect daily functioning.

The term “spectrum” refers to the wide range of symptoms, skills, and levels of disability in functioning that can occur in people with ASD. Some children and adults with ASD are fully able to perform all activities of daily living while others require substantial support to perform basic activities.

ASD occurs in every racial and ethnic group, and across all socioeconomic levels. However, boys are significantly more likely to develop ASD than girls. The latest analysis from the Centers for Disease Control and Prevention estimates that 1 in 59 [Ref 1] children has ASD.


Ref 1: CDC Report

Where can I Find More Information About Autism Research?

NIH Brain Resources and Information Network (BRAIN) at:

BRAIN
P.O. Box 5801
Bethesda, MD 20824
800-352-9424
http://ninds.nih.gov

Information also is available from the following organizations:

Centers for Disease Control and Prevention (CDC)
U.S. Department of Health and Human Services
1600 Clifton Road
Atlanta, GA 30333
[email protected]
https://www.cdc.gov/
Tel: 800-311-3435; 404-639-3311; 404-639-3543

National Institute of Child Health and Human Development (NICHD)
National Institutes of Health, DHHS
31 Center Drive, Rm. 2A32 MSC 2425
Bethesda, MD 20892-2425
http://www.nichd.nih.gov
Tel: 301-496-5133
Fax: 301-496-7101

National Institute on Deafness and Other Communication Disorders (NIDCD)
National Institutes of Health, DHHS
31 Center Drive, MSC 2320
Bethesda, MD 20892-2320
[email protected]
http://www.nidcd.nih.gov
Tel: 301-496-7243; 800-241-1044; 800-241-1055 (TTY)

National Institute of Environmental Health Sciences (NIEHS)
National Institutes of Health, DHHS
111 T.W. Alexander Drive
Research Triangle Park, NC 27709
[email protected]
http://www.niehs.nih.gov
Tel: 919-541-3345

National Institute of Mental Health (NIMH)
National Institutes of Health, DHHS
6001 Executive Blvd. Rm. 8184, MSC 9663
Bethesda, MD 20892-9663
[email protected]
http://www.nimh.nih.gov
Tel: 301-443-4513; 866-415-8051; 301-443-8431 (TTY)
Fax: 301-443-4279

Association for Science in Autism Treatment
P.O. Box 1447
Hoboken, NJ 07030
[email protected]
http://www.asatonline.org

Autism National Committee (AUTCOM)
P.O. Box 429
Forest Knolls, CA 94933
http://www.autcom.org

Autism Network International (ANI)
P.O. Box 35448
Syracuse, NY 13235-5448
[email protected]
http://www.autismnetworkinternational.org

Autism Research Institute (ARI)
4182 Adams Avenue
San Diego, CA 92116
[email protected]
http://www.autismresearchinstitute.com
Tel: 619-281-7165; 866-366-3361
Fax: 619-563-6840

Autism Science Foundation
28 West 39th Street
Suite 502
New York, NY 10018
[email protected]
http://www.autismsciencefoundation.org
Tel: 212-391-3913
Fax: 212-228-3557

Autism Society of America
4340 East-West Highway
Suite 350
Bethesda, MD 20814
http://www.autism-society.org
Tel: 301-657-0881; 800-3AUTISM (328-8476)
Fax: 301-657-0869

Autism Speaks, Inc.
1 East 33rd Street
4th Floor
New York, NY 10016
[email protected]
http://www.autismspeaks.org
Tel: 212-252-8584; 888-288-4762
Fax: 212-252-8676

MAAP Services for Autism, Asperger Syndrome, and PDD
P.O. Box 524
Crown Point, IN 46308
[email protected]
http://www.aspergersyndrome.org
Tel: 219-662-1311
Fax: 219-662-1315

“Autism Spectrum Disorder Fact Sheet”, NINDS, Publication date September 2015.

NIH Publication No. 15-1877

Back to Autism Spectrum Disorder Information Page

Do symptoms of autism change over time?

People often ask if symptoms of autism change over time. For many children, symptoms improve with age and behavioral treatment. During adolescence, some children with Autism Spectrum Disease (ASD) may become depressed or experience behavioral problems, and their treatment may need some modification as they transition to adulthood. People with ASD usually continue to need services and supports as they get older, but depending on severity of the disorder, people with ASD may be able to work successfully and live independently or within a supportive environment.

What is the Autism Prevalence in the US?

The federal government’s Centers for Disease Control and Prevention (CDC) estimates that about 1 in 59 children has been identified with Autism Spectrum Disorder (ASD) (or 16.8 per 1,000 8-year-olds) in the United States. These autism prevalence estimates from the Autism and Developmental Disabilities Monitoring (ADDM) Network are based on data collected from health and special education records of children living in 11 communities across the United States during 2014. These 11 communities comprised 8% of the United States population of 8-year-olds in 2014. Information was collected on children who were 8 years old because previous work has shown that, by this age, most children with ASD have been identified for services. The Autism and Developmental Disabilities Monitoring (ADDM) Network is the only collaborative network to track the number and characteristics of children with autism spectrum disorder (ASD) in multiple communities in the United States.

Current ADDM Network Sites - Autism Prevalence

Source: CDC

In 2007, CDC’s ADDM Network first reported that about 1 in 150 children had ASD (based on 2002 data from 14 communities). Then, in 2009, the ADDM Network reported that 1 in 110 children had ASD (based on 2006 data from 11 communities). And, in 2012, the ADDM Network reported that 1 in 88 children had ASD (based on 2008 data from 14 communities). In 2014, the ADDM Network reported that about 1 in 68 children had ASD (based on 2010 data from 11 communities). The estimated autism prevalence stayed about the same between 2010 and 2012, as reported in 2016.

Autism Prevalence in Arizona

  • About 1 in 71 children has been identified with Autism Spectrum Disorder (ASD) (or 14.0 per 1,000 8-year-olds) in Arizona in 2014.
  • Fewer than half of the children identified with ASD received a comprehensive developmental evaluation by 3 years of age despite concerns about developmental delays. This lag between first concern and first developmental evaluation leads to delays in diagnosis and connection to the services and support the children need.
  • Although ASD can be diagnosed as early as 2 years of age, in Arizona, the median age of diagnosis by a community provider is 4 years and 8 months of age.
  • Differences between the percentage of boys and girls identified with ASD continue. It may be that boys are at greater risk for ASD, and/or it may be that girls are under-identified due to other factors.
  • Hispanic children are less likely to be identified with ASD compared to non-Hispanic children in Arizona. This may reflect cultural differences, socioeconomic differences, and/or differences in access to diagnostic and therapeutic services.
  • More children with average intelligence levels are being identified with ASD. This may reflect increased awareness of the signs of autism, differentiated from other developmental disabilities.

Autism Prevalence in Arkansas

  • About 1 in 77 children has been identified with Autism Spectrum Disorder (ASD) in Arkansas in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • Differences between the percentage of boys and girls identified with ASD continue. It may be that boys are at greater risk for ASD and/or it may be that girls are under-identified due to others factors, such as how providers diagnose and document ASD symptoms among boys versus girls.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were diagnosed with ASD by a community provider by 4 years, 11 months of age.
  • Efforts may be directed toward evaluating and diagnosing all children with ASD as early as possible so that they can be connected to the services they need.

Autism Prevalence in Colorado

  • About 1 in 72 children has been identified with Autism Spectrum Disorder (ASD) in Colorado in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • Hispanic children were less likely to be identified with ASD than white or black children. Research does not show that being Hispanic makes a child less likely to develop ASD. This difference in identification may reflect cultural and/or socioeconomic differences, such as delayed or lack of access to services, as compared to other groups in Colorado.
  • Despite the developmental concerns noted in many of the children’s records by 3 years of age, less than half of children identified with ASD received a comprehensive developmental evaluation by this same age. The lag between first concern and first developmental evaluation may affect when children are being diagnosed and connected to the services they need.
  • Although ASD can be diagnosed as early as 2 years of age, about half of children were not diagnosed with ASD by a community provider until after age 4 years and 3 months. Of the children identified with ASD in Colorado through the CO-ADDM Project, only 58 percent had either eligibility for autism special education services or a clinical autism diagnosis documented in their records.

Autism Prevalence in Georgia

  • About 1 in 59 children has been identified with Autism Spectrum Disorder (ASD) in Georgia in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • The proportion of black and white children identified with ASD was about the same. However, Hispanic children were less likely to be identified with ASD than black or white children. This may reflect cultural and/or socioeconomic differences, such as language barriers and delayed or lack of access to services, as compared to white and black children in Georgia.
  • Though developmental concerns were noted in many children’s records by 3 years of age, less than half of children identified with ASD received a comprehensive developmental evaluation by this same age. The lag between first concern and first developmental evaluation may affect when children are diagnosed and connected to the services they need.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were not diagnosed with ASD by a community provider until after 4 years, 5 months of age.
  • Efforts may be directed toward evaluating and diagnosing all children with ASD as early as possible so that they can be connected to the services they need.

Autism Prevalence in Maryland

  • About 1 in 50 children has been identified with Autism Spectrum Disorder (ASD) in Maryland in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • The percentage of children with ASD is high in this area of Maryland.
  • Differences between the percentage of boys and girls identified with ASD continue. It may be that boys are at greater risk for ASD and/or it may be that girls are under-identified due to others factors, such as how providers diagnose and document ASD symptoms among boys versus girls.
  • Despite the developmental concerns noted in many (92 percent) of the children’s records by 3 years of age, only slightly more than half (56 percent) of children identified with ASD received a comprehensive developmental evaluation by this same age. The lag between first concern and first developmental evaluation may affect when children are being diagnosed and connected to the services they need.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were diagnosed with ASD by a community provider by 4 years, 4 months of age.
  • Efforts may be directed toward evaluating and diagnosing all children with ASD as early as possible so that they can be connected to the services they need.

Autism Prevalence in Minnesota

  • About 1 in 42 children has been identified with Autism Spectrum Disorder (ASD) in Minnesota in 2014.
  • This is the first time MN has been a part of the ADDM network, and we are building our geographic area. The findings in this report reflect a small number of children concentrated in a large metropolitan area. The higher prevalence estimate is not unanticipated for a large metropolitan area.
  • In MN there were differences between percentage of boys and girls identified, with more boys than girls. This is consistent with previous estimates.
  • We found varying prevalence rates across racial and ethnic groups in Minnesota. The small number of children in some of these groups makes it difficult to determine whether the rates of children with autism truly are different across groups. As the geographic area for MN-ADDM grows, we will be better able to judge whether there are true differences in prevalence estimates. If differences are found, it will be important to focus on general health disparities that may influence these differences.
  • In Minnesota, we identify autism much later than when first concerns are reported. The lag between first concern and diagnosis is concerning due to what we know about the importance of early intervention.

Autism Prevalence in Missouri

  • About 1 in 71 children has been identified with Autism Spectrum Disorder (ASD) in Missouri in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • Differences between the percentage of boys and girls identified with ASD continue. It may be that boys are at greater risk for ASD and/or it may be that girls are under-identified due to others factors, such as how providers diagnose and document ASD symptoms among boys versus girls.
  • Despite the developmental concerns noted in many of the children’s records by 3 years of age, less than half of children identified with ASD received a comprehensive developmental evaluation by this same age. The lag between first concern and first developmental evaluation may affect when children are being diagnosed and connected to the services they need.
  • Efforts may be directed toward evaluating and diagnosing all children with ASD as early as possible so that they can be connected to the services they need.

Autism Prevalence in New Jersey

  • About 1 in 34 children has been identified with Autism Spectrum Disorder (ASD) in New Jersey in 2014.
  • The percentage of children with ASD increased in New Jersey, from about 2.5 percent in 2012 to about 3 percent, in 2014. Rising numbers of children with ASD need services and support, now, and will require significant resources as they grow into adolescence and adulthood.
  • Boys continue to have a higher ASD prevalence than girls. In 2014, almost 4 percent of boys in the area were identified with ASD, compared to about 1 percent of girls.
  • ASD prevalence in New Jersey did not vary by race or ethnicity in 2014, unlike in 2012, suggesting that progress has been made in identifying all children with ASD.
  • In spite of the fact that developmental concerns are noted in many of children’s records by 3 years of age, fewer than half of children with ASD received a comprehensive developmental evaluation by this same age. This lag between first concern and first developmental evaluation may affect when children are being diagnosed and connected to the services they need.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were not diagnosed with ASD by a community provider until after 4 years of age.
  • Future efforts may emphasize the importance of screening young children with standard tools and connecting families to needed services before 3 years of age.
  • The percentage of children with ASD continues to be higher in New Jersey compared to other areas in the United States where CDC tracks ASD. It is not known exactly why this is so, but geographic differences in evaluation and diagnostic practices for children with developmental concerns may play a role.

Autism Prevalence in North Carolina

  • About 1 in 57 children has been identified with Autism Spectrum Disorder (ASD) in North Carolina in 2014.
  • Many children are living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • Hispanic children were less likely to be identified with ASD than white or black children. This may reflect cultural and/or socioeconomic differences, such as delayed or lack of access to services, as compared to other groups in North Carolina.
  • Among the areas where CDC tracks ASD across the United States, the area in central North Carolina had the highest percentage of children identified with ASD who had received a comprehensive developmental evaluation by 3 years of age. This is good news, but there is still more to be done to ensure that all children are evaluated as soon as concerns about their development are identified.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were not diagnosed with ASD by a community provider until after 3 years, 4 months of age.
  • Efforts may be directed toward evaluating and diagnosing all children with ASD as early as possible so that they can be connected to the services they need.

Autism Prevalence in Tennessee

  • About 1 in 64 children has been identified with Autism Spectrum Disorder (ASD) in Tennessee in 2014.
  • There are many children living with ASD who need services and support, now and as they grow into adolescence and adulthood.
  • This is the first time data from ADDM are available for TN. The percentage of children with ASD in TN (1.6 percent) was very similar to current estimates across the United States (1.7 percent).
  • Despite the developmental concerns noted in many of the children’s records by 3 years of age, only about one-third (34 percent) of children with ASD received a comprehensive evaluation by this same age. This gap between early concerns and first developmental evaluation may affect when children are diagnosed and the intervention services they need.
  • ASD can be diagnosed as early as 2 years of age; however, about half of children were not diagnosed with ASD by a community provider until after 4 years, 8 months of age.

Autism Prevalence in Wisconsin

  • About 1 in 71 children has been identified with Autism Spectrum Disorder (ASD) in Wisconsin in 2014.
  • The percentage of children with ASD increased in southeastern Wisconsin from about 1.1 percent in 2012 to about 1.4 percent in 2014.
  • Hispanic and black children were less likely to be identified with ASD than white children. This may reflect cultural and/or socioeconomic differences, such as delayed or lack of access to services, as compared to white children in Wisconsin.
  • Despite the developmental concerns noted in many of the children’s records by 3 years of age, less than half of children identified with ASD received a comprehensive developmental evaluation by this same age. The lag between first concern and first developmental evaluation may affect when children are being diagnosed and connected to the services they need.
  • Efforts may be directed toward early developmental screening of all children so those who have ASD can be identified early and connected to the services they need.