U.S. autism numbers rose in 2022, according to new CDC report

A new report from the U.S. Centers for Disease Control and Prevention (CDC) suggests autism diagnosis rates continue to rise in the U.S., sparking inflammatory rhetoric from government officials, while experts largely attribute the trend to improved screening and better understanding of the condition.

The CDC reported Tuesday that an estimated one in 31 eight-year-olds in the U.S. have autism, using data from 14 states and Puerto Rico in 2022. The previous estimate — from 2020 — was one in 36.

The CDC checked health and school records for eight-year-olds for its estimate, because most cases are diagnosed by that age.

Boys continue to be diagnosed more than girls, and the highest rates are among children who are Asian/Pacific Islander, Indigenous and Black.

The CDC acknowledges that its report does not cover the entire country or generate "nationally representative [autism spectrum disorder] prevalence estimates."

The numbers also vary widely by location — from one in 103 in Laredo, Texas, to one in 19 in California.

CDC researchers say this might be due to differences in availability of services for early detection and evaluation. For example, an initiative in California has seen hundreds of local pediatricians trained to screen and refer children for early assessments, and the state also has numerous regional centres that provide evaluations.

In response to the report, U.S. Health and Human Services (HHS) Secretary Robert F. Kennedy, Jr. claimed in a statement that the "autism epidemic is running rampant," and that its "risks and costs… are a thousand times more threatening to our country than COVID-19."

The Autism Society of America says the rise from 2020 may reflect several factors, including greater awareness and improved screening and diagnostics.

"This rise in prevalence does not signal an 'epidemic' as narratives are claiming — it reflects diagnostic progress, and an urgent need for policy decisions rooted in science and the immediate needs of the Autism community," the organization said in a statement.

Canada's most recent numbers are from 2019, when the Public Health Agency of Canada said one in 50 kids aged 1-17 have been diagnosed with autism spectrum disorder (ASD), with males being diagnosed approximately four times more frequently than females.

Remi Yergeau, Canada Research Chair in critical disability studies and communication at Carleton University, says the CDC report is just a "snapshot" and doesn't give the full story behind the numbers.

Yergeau says clinicians have become more attuned to recognizing autism and the various ways in which autistic traits manifest in people.

"People like to make comparisons, saying things like, 'When I was a kid, there were no autistic people,'" Yergeau said. "They forget about things like institutionalization and how diagnoses have shifted, so people who might have been previously diagnosed with another condition are now being diagnosed with autism."

For decades, the diagnosis was rare, given only to kids with severe problems communicating or socializing and those with unusual, repetitive behaviours.

As late as the early 1990s, only one in 10,000 children were diagnosed with autism. Around that time, the term became a shorthand for a group of related conditions known as ASD and the number of kids labelled as having some form of autism began to balloon.

In the first decade of this century, the U.S. estimate rose to one in 150. In 2018, it was one in 44. In 2020, it was up to one in 36.

Yergeau says a "language of panic" tends to follow these reports, and worries about the harms of Kennedy's "dehumanizing" rhetoric.

"There's a very real way in which that that kind of panic translates to not great outcomes for autistic people — like, to see disability and disabled people as something to be feared," they said.

"When people create that rhetoric of panic, then they create an accompanying rhetoric that we must do anything we can to solve it. And really bad things can happen when you take that particular approach out of this perceived desperation."

Kennedy vowed last week that the country's top health agency will pinpoint the cause of autism by September, and promised to "eliminate those exposures," in an announcement that raised concerns among medical experts and advocates.

Kennedy and anti-vaccine advocates have long pushed a discredited theory about childhood vaccines, pointing at a preservative called thimerosal that is no longer in most childhood vaccines, or theorizing that autism may be the cumulative effect of multiple vaccinations.

Decades of research have found no links to vaccines and have shown that genetics plays a large role in autism, but that there's no specific "autism gene." There are no blood or biologic tests for autism, which is diagnosed by making judgments about a person's behaviour.

The U.S. National Institutes of Health, which spends more than $300 million US yearly researching autism, lists some possible risk factors such as prenatal exposure to pesticides or air pollution, extreme prematurity or low birth weight, certain maternal health problems or parents conceiving at an older age.

Kennedy hired David Geier, a man who has repeatedly claimed a link between vaccines and autism, and who was fined by the state of Maryland for practising medicine on a child without a doctor's licence, to lead the autism research effort.