Autism

15 November 2023

Key facts

  • Autism – also referred to as autism spectrum disorder ̶ constitutes a diverse group of conditions related to development of the brain.
  • About 1 in 100 children has autism.
  • Characteristics may be detected in early childhood, but autism is often not diagnosed until much later.
  • The abilities and needs of autistic people vary and can evolve over time. While some people with autism can live independently, others have severe disabilities and require life-long care and support.
  • Evidence-based psychosocial interventions can improve communication and social skills, with a positive impact on the well-being and quality of life of both autistic people and their caregivers.
  • Care for people with autism needs to be accompanied by actions at community and societal levels for greater accessibility, inclusivity and support.

Overview

Autism spectrum disorders (ASD) are a diverse group of conditions. They are characterized by some degree of difficulty with social interaction and communication. Other characteristics are atypical patterns of activities and behaviours, such as difficulty with transition from one activity to another, a focus on details and unusual reactions to sensations.

The abilities and needs of autistic people vary and can evolve over time. While some people with autism can live independently, others have severe disabilities and require life-long care and support. Autism often has an impact on education and employment opportunities. In addition, the demands on families providing care and support can be significant. Societal attitudes and the level of support provided by local and national authorities are important factors determining the quality of life of people with autism.

Characteristics of autism may be detected in early childhood, but autism is often not diagnosed until much later.

People with autism often have co-occurring conditions, including epilepsy, depression, anxiety and attention deficit hyperactivity disorder as well as challenging behaviours such as difficulty sleeping and self-injury. The level of intellectual functioning among autistic people varies widely, extending from profound impairment to superior levels.

Epidemiology

It is estimated that worldwide about 1 in 100 children has autism (1). This estimate represents an average figure, and reported prevalence varies substantially across studies. Some well-controlled studies have, however, reported figures that are substantially higher. The prevalence of autism in many low- and middle-income countries is unknown.

Causes

 

Available scientific evidence suggests that there are probably many factors that make a child more likely to have autism, including environmental and genetic factors.

Extensive research using a variety of different methods and conducted over many years has demonstrated that the measles, mumps and rubella vaccine does not cause autism. Studies that were interpreted as indicating any such link were flawed, and some of the authors had undeclared biases that influenced what they reported about their research (2,3,4).

Evidence also shows that other childhood vaccines do not increase the risk of autism. Extensive research into the preservative thiomersal and the additive aluminium that are contained in some inactivated vaccines strongly concluded that these constituents in childhood vaccines do not increase the risk of autism.

 

Assessment and care

A broad range of interventions, from early childhood and across the life span, can optimize the development, health, well-being and quality of life of autistic people. Timely access to early evidence-based psychosocial interventions can improve the ability of autistic children to communicate effectively and interact socially. The monitoring of child development as part of routine maternal and child health care is recommended.

It is important that, once autism has been diagnosed, children, adolescents and adults with autism and their carers are offered relevant information, services, referrals, and practical support, in accordance with their individual and evolving needs and preferences.

The health-care needs of people with autism are complex and require a range of integrated services, that include health promotion, care and rehabilitation. Collaboration between the health sector and other sectors, particularly education, employment and social care, is important.

Interventions for people with autism and other developmental disabilities need to be designed and delivered with the participation of people living with these conditions. Care needs to be accompanied by actions at community and societal levels for greater accessibility, inclusivity and support.

Human rights

All people, including people with autism, have the right to the enjoyment of the highest attainable standard of physical and mental health.

And yet, autistic people are often subject to stigma and discrimination, including unjust deprivation of health care, education and opportunities to engage and participate in their communities.

People with autism have the same health problems as the general population. However, they may, in addition, have specific health-care needs related to autism or other co-occurring conditions. They may be more vulnerable to developing chronic noncommunicable conditions because of behavioural risk factors such as physical inactivity and poor dietary preferences, and are at greater risk of violence, injury and abuse.

People with autism require accessible health services for general health-care needs like the rest of the population, including promotive and preventive services and treatment of acute and chronic illness. Nevertheless, autistic people have higher rates of unmet health-care needs compared with the general population. They are also more vulnerable during humanitarian emergencies. A common barrier is created by health-care providers’ inadequate knowledge and understanding of autism.

WHO resolution on autism spectrum disorders 

In May 2014, the Sixty-seventh World Health Assembly adopted a resolution entitled Comprehensive and coordinated efforts for the management of autism spectrum disorders, which was supported by more than 60 countries.

The resolution urges WHO to collaborate with Member States and partner agencies to strengthen national capacities to address ASD and other developmental disabilities.

WHO response

WHO and partners recognize the need to strengthen countries' abilities to promote the optimal health and well-being of all people with autism.

WHO's efforts focus on:

  • increasing the commitment of governments to taking action to improve the quality of life of people with autism;
  • providing guidance on policies and action plans that address autism within the broader framework of health, mental and brain health and disabilities;
  • contributing to strengthening the ability of the health workforce to provide appropriate and effective care and promote optimal standards of health and well-being for people with autism; and
  • promoting inclusive and enabling environments for people with autism and other developmental disabilities and providing support to their caregivers.

WHO Comprehensive mental health action plan 2013–2030 and World Health Assembly Resolution WHA73.10 for “global actions on epilepsy and other neurological disorders” calls on countries to address the current significant gaps in early detection, care, treatment and rehabilitation for mental and neurodevelopmental conditions, which include autism. It also calls for counties to address the social, economic, educational and inclusion needs of people living with mental and neurological disorders, and their families, and to improve surveillance and relevant research.


References

1. Global prevalence of autism: A systematic review update. Zeidan J et al. Autism Research 2022 March.

2. Wakefield's affair: 12 years of uncertainty whereas no link between autism and MMR vaccine has been proved. Maisonneuve H, Floret D. Presse Med. 2012 Sep; French (https://www.ncbi.nlm.nih.gov/pubmed/22748860).

3. Lancet retracts Wakefield’s MMR paper. Dyer C. BMJ 2010;340:c696. 2 February 2010 (https://pubmed.ncbi.nlm.nih.gov/20124366/)

 

4. Kmietowicz Z. Wakefield is struck off for the “serious and wide-ranging findings against him” BMJ 2010; 340 :c2803 doi:10.1136/bmj.c2803 (https://www.bmj.com/content/340/bmj.c2803)