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Health Concerns


About Autism Spectrum Disorders

Autism Spectrum Disorders (ASD) is a complex, lifelong condition that affects individuals from all walks of life, as well as their families, friends and caregivers. Autism is a spectrum disorder, defined by certain behaviours which come in combinations and in degrees of intensity that vary in each child and adult affected.

Autism Facts

  • Studies show that signs of autism are usually present by three years of age and it is four times more prevalent in boys than in girls.
  • ASD can be characterized along a spectrum, with symptoms ranging from mild to severe and often including repetitive behaviour and difficulties with social interaction, communication and learning (in the usual settings).
  • International studies indicate that about one in every 150-160 children has autism.
  • Diagnosis involves a number of different measures and screening tools, many based on observation by a team of professionals.

Many individuals with ASD have trouble communicating with others or difficulty with regular social interactions. Other signs include a tendency toward repetitive behaviours, and unusual or severely limited activities and interests. ASD develops differently from person to person, and the effects can range from relatively mild to debilitating. Unlike some conditions, there is no "typical" person with ASD.

No one knows the cause of autism, although there is strong evidence that genetics plays a role. Ongoing research is investigating many possibilities including genetic influences, pre- and post-natal development, environmental factors and immune deficiencies. ASD is not infectious, cannot be caught and, is not caused by parents' behaviour or style of parenting.

Despite the frequency of ASD, there is much that is unknown about these disorders. More research is needed to better understand the incidence, causes, and most effective interventions.

Related Resources

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Government of Canada

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