How common is autism?
The global prevalence of autism spectrum disorder (ASD) varies significantly across different regions, with recent studies indicating a range within and across regions. A systematic review (2022) update noted that global autism prevalence has a median value of 100 per 10,000 individuals, with the range spanning from 1.09 per 10,000 to 436.0 per 10,000.[1] This update reflects the wide variability in autism prevalence estimates worldwide, highlighting the challenges in accurately measuring this condition globally due to differences in study methodologies, diagnostic criteria, and access to services.
According to the World Population Review (2024), in 2019 the United Kingdom had the highest autism prevalence, with a rate of 700.07 per 100,000 individuals (0.70%). The other countries in the top five were Sweden (661.85; 0.66%), Japan (604.72; 0.60%), the US (603.38; 0.60%), and the Netherlands (591.54; 0.59%).[2]
Another study on global prevalence found that among the three geographical regions included in the sub-group analysis, the pooled prevalence of ASD was significantly higher in North America (1.01%), compared with estimates obtained for Europe (0.73%) and Asia (0.41%). When analyzed by income groups, the highest prevalence was in high-income countries (0.79%), and the lowest–in lower middle-income ones (0.32%). Based on country level, the highest prevalence of ASD was reported in the USA (1.12%), followed by Sweden (0.90%) and Denmark (0.73%); the lowest estimates were calculated for Taiwan (0.11%), France (0.32%), and China (0.42%).[3]
The current prevalence of autism in the United States is estimated to be 1 in 36 (2.8%) among 8-year-old children, according to 2024 figures from the Centers for Disease Control and Prevention (CDC).[4] This rate is up from the CDC’s 2018 estimate of 1 in 44 (2.3%) children, and significantly increased from their 2000 estimate of 1 in 150 (0.67%) children.[5].
A study in Japan found that the adjusted prevalence of autism spectrum disorders in 5-year-old children was 3.22%.[6]
The prevalence of autism in India varies significantly between urban and rural areas. One community-based assessment of neurodevelopmental disorders in children found that in North Goa, a largely urban coastal region, the autism rate is about 0.4%, while in Palwal, a rural area in north-central India, it is approximately 1.8%.[7]
A separate systematic review and meta-analysis of the published studies evaluating the prevalence of autism spectrum disorder in the Indian population highlighted the scarcity of high-quality population-based epidemiological studies on ASD in India. The results from rural and urban settings combined suggest a prevalence rate ranging from 0.09% in urban children aged 0-15 years to 0.11% in rural children aged 1-18 years.[8]
These studies underscore the need for more comprehensive research to better understand the prevalence and impact of autism in India, considering the vast socio-economic and cultural diversity across the country.
The prevalence of autism spectrum disorder in Europe varies across different regions and studies, reflecting a complex picture of this condition’s distribution. In 2024, developed countries in Europe had the lowest global autism rates, with France boasting the best at 1 in 144 people (0.69%), and Portugal right behind with 1 in 142 (0.71%).[9] However, research from 2011-13 found that ASD affected around 1 in 100 (0.1%) people across Europe.[10] By 2022, the pooled prevalence rate was estimated at 0.8-1.4%.[11] These estimates align with a broad observation of the increasing number of reported cases of autism over the past 30 years in all countries where prevalence studies have been conducted.
In Australia, it is estimated that approximately 1 in 40 Australians is on the autism spectrum, with prevalence rates continuing to rise.[12]
In Latin America, the prevalence rate is difficult to stipulate due to the limited number of epidemiological studies available. Of the few countries with known prevalence rates, numbers range from 170 to 520.6 in every 100,000 [RD9] (1.7-5.2%) individuals in Venezuela and Argentina, respectively.[13],[14]
The prevalence of ASD in Africa is not well-established, with varying estimates reported in different African countries. Lagunju et al. reported a prevalence of 2.3% in Nigeria[15], while Kakooza-Mwesige recorded a prevalence of 0.68% in Uganda.[16] Zeglam found a prevalence of 0.33% in Libya[17], and Hewitt reported a prevalence of 2.07% in Somalia.[18] A multinational study that included Egypt and Tunisia reported a prevalence of 33.6% and 11.5%, respectively.[19] However, these varying estimates underscore the need for a more comprehensive and standardised evaluation of ASD prevalence across the continent.
Autism is found in all racial, ethnic, and socioeconomic groups, albeit with varying prevalence rates. It’s important to recognize that while autism is relatively common, each individual with autism is unique, and their experiences and needs may vary widely.
[1] Zeidan, J. et al. Global prevalence of autism: A systematic review update. Autism Research (2022), 15(5), 778–790.
[2] World Population Review. Autism Rates by Country 2024. Available at: https://worldpopulationreview.com/country-rankings/autism-rates-by-country (accessed: 9 Jun 2024).
[3] Talantseva, O. I. et al. The global prevalence of autism spectrum disorder: A three-level meta-analysis. Frontiers in Psychiatry (2023), 14, 1071181.
[4] CDC (2024) Data and Statistics on Autism Spectrum Disorder. Available at https://www.cdc.gov/autism/data-research/index.html (accessed: 9 Jun 2024)
[5] Maenner, Matthew J. et al. Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years – Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2020 (2023). Available at: https://www.intechopen.com/chapters/84388 (accessed: 11 July 2024).
[6] Saitto, M., Sakamoto, Y., Terui, A. (2022) Epidemiology of ASD in Preschool-age Children in Japan. Autism Spectrum Disorders – Recent Advances and New Perspectives.
[7] Arora, NK et al. Neurodevelopmental disorders in children aged 2-9 years: Population-based burden estimates across five regions in India. PLoS Med (2018);15:e1002615.
[8] Chauhan, Anil et al. Prevalence of autism spectrum disorder in Indian children: A systematic review and meta-Analysis. Neurology India. (2019) 67. 100. 10.4103/0028-3886.253970.
[9] https://worldpopulationreview.com/country-rankings/autism-rates-by-country
[10] Autism Europe. Prevalence rate of autism. Available at https://www.autismeurope.org/about-autism/prevalence-rate-of-autism/ (accessed: 9 Jun 2024)
[11] Sacco, Rosemarie et al. The Prevalence of Autism Spectrum Disorder in Europe. (2022). https://www.intechopen.com/chapters/84388
[12] Autism Spectrum Australia (2024) At least 1 in 40 Australians are Autistic. https://www.aspect.org.au/news/1-in-40-australians-autistic-waud
[13] Cecilia Montiel-Nava, JAP. Epidemiological findings of pervasive developmental disorders in a Venezuelan study. Autism. (2008) 12:191–202.
[14] Lejarraga, H et al. Screening for developmental problems at primary care level: a field programme in San Isidro, Argentina. Paediatr Perinat Epidemiol. (2008) 22:180–7.
[15] Lagunju IA, Bella-Awusah TT, Omigbodun OO. Autistic disorder in Nigeria: profile and challenges to management. Epilepsy Behav (2014) 39:126–129.
[16] Kakooza-Mwesige A, Ssebyala K, Karamagi C, et al. Adaptation of the “ten questions” to screen for autism and other neurodevelopmental disorders in Uganda. Autism (2014) 18:447–457.
[17] Zeglam A, Maouna A. Prevalence of autistic spectrum disorders in Tripoli, Libya: the need for more research and planned services. East Mediterr Health J (2012) 18:184–188.
[18] Hewitt A, Hall-Lande J, Hamre K, et al. Autism spectrum disorder (ASD) prevalence in Somali and non-Somali children. J Autism Dev Disord (2016) 46:2599–2608.
[19] Seif Eldin A, Habib D, Noufal A, et al. Use of M-CHAT for a multinational screening of young children with autism in the Arab countries. Int Rev Psychiatry (2008) 20:281–289.
