Beyond the "Epidemic" Headlines: What the 1-in-31 Autism Rate Really Means

Understanding the Science Behind Rising Autism Diagnoses in a World of Political Soundbites

Autism has been all over the news with some eye-catching headlines:

"Autism rates reach new record!"

"1 in 31 children now diagnosed with autism!"

“There is an autism epidemic!”

Perhaps you've even heard our new Health Secretary RFK Jr. promising to identify the cause of autism by September—just five months from now.

But what do these numbers really mean? Are we truly experiencing an "epidemic" as some are claiming? Let's dive into the facts behind the latest CDC report and separate scientific reality from political rhetoric. Let’s discuss…

The Latest CDC Report: What You Need to Know

The CDC recently released their biennial report from the Autism and Developmental Disabilities Monitoring Network (ADDM), which provides a snapshot of autism spectrum disorder in children across the US.

According to the April 2025 report, the overall prevalence of autism is now 1 in 31 (3.2%) among 8-year-olds in 2022. This represents an increase from previous reports (1 in 36 in 2020, and 1 in 150 in 2000). For 4-year-old children, the autism prevalence was 1 in 34 (2.9%), also higher than in previous years.

Why are ADDM Network Reports Useful?

According to the CDC, the main goals of the ADDM Network are to:

• Describe the population of children with autism spectrum disorder (ASD) and cerebral palsy (CP)

• Compare how common ASD or CP is in different areas of the country

• Measure progress in early ASD identification

• Understand when children are diagnosed with CP

• Identify changes in ASD or CP occurrence over time

• Understand the impact of ASD, CP, and related conditions in US communities

These comprehensive monitoring efforts provide critical data that helps researchers, clinicians, and policymakers better understand autism trends and allocate resources appropriately. Insights help contextualize the headline numbers within broader demographic and diagnostic patterns.

Key Findings from the Report

Beyond the headline numbers, the report revealed several important patterns:

• Regional variation: Autism rates vary widely by location, with Texas showing much lower rates than California.

• Gender differences: Males are about 3 times more likely to receive an ASD diagnosis than females. This gap has been narrowing (previously 4:1), likely due to improved identification of autism in females.

• Racial/ethnic patterns: Rates were higher among Asian, Black, Hispanic, and American Indian/Alaska Native children compared to White children—a shift from past patterns when White children had higher diagnosis rates.

• Earlier identification: Children born in 2018 were more likely to be evaluated and identified with autism by age 4 compared to those born in 2014.

Why are Autism Diagnoses Increasing?

This is the million-dollar question that has everyone talking. But before we jump to conclusions about environmental toxins or other potential causes, the scientific consensus points to several key factors:

1. Improved awareness and screening: The Autism Society of America notes that better screening tools, greater awareness, and increased access to diagnostic services account for much of the increase.

2. Changes in diagnostic criteria: The definition of autism has evolved significantly. Studies have found that children who were once classified with intellectual disabilities are now often diagnosed with ASD—a phenomenon called diagnostic substitution.

3. Expanded definition: The DSM (Diagnostic and Statistical Manual of Mental Disorders) has dramatically changed how autism is defined. Autism wasn't even mentioned in the DSM in the 1970s. By 2013, all subtypes were placed under the broad umbrella of "autism spectrum disorder," allowing more children—especially those with milder symptoms—to meet the diagnostic criteria.

4. Demographic shifts: Recent data shows rates were higher among Asian, Black, Hispanic, and American Indian/Alaska Native children compared to White children—a shift from past patterns when White children had higher diagnosis rates. This closing demographic gap is strong evidence of improved identification rather than a true epidemic.

5. Regional variation: The CDC report revealed that autism rates vary widely by location. For example, ASD rates in Texas were much lower than the rates in California. Such geographic variation further suggests that diagnostic practices and recognition play significant roles in prevalence differences.

While some biological or environmental factors might play a role (autism is likely influenced by genetic differences), most experts view the rising numbers as primarily reflecting our ability to recognize and diagnose autism across its full spectrum.

Additional Factors to Consider

Parental Age: Studies have found that advanced parental age, particularly paternal age above 34, is associated with a slightly increased likelihood of autism in offspring. However, this represents just one small factor compared to the predominant role of better recognition and diagnostic changes.

Genetic Foundations: While not explaining the increase in diagnoses over time, it's worth noting that scientific research clearly shows autism has strong genetic foundations, with studies suggesting genetics accounts for a significant portion of autism risk, ranging from 70% to 90%. The brain differences associated with autism typically develop in utero during the first trimester—long before external interventions occur.

No, We're Not Experiencing an "Epidemic"

Despite what you might hear from certain political figures, the rising numbers do not constitute an "epidemic." Here's why:

An epidemic is defined by the CDC as "an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area".

The increase in autism diagnoses fails to meet this definition because:

1. It has been gradual over decades, not sudden.

2. Autism is not a disease—it's a neurodevelopmental condition that represents a different way of thinking and experiencing the world.

What’s This About an Autism Registry?

While this article focuses on understanding prevalence rates, it's worth noting that HHS under Secretary Kennedy has initiated a sweeping data collection effort that merits careful attention. However, in a significant development this past Friday, an HHS official clarified: "We are not creating an autism registry. The real-world data platform will link existing datasets to support research into causes of autism and insights into improved treatment strategies." This directly contradicts NIH Director Dr. Jay Bhattacharya's earlier announcement about developing "national disease registries, including a new one for autism."

This reversal came after considerable backlash from advocacy groups and researchers, with some clinicians reporting that patients were canceling appointments and requesting that their data be removed over privacy concerns.

The research initiative will continue, focused on "understanding the causes of ASD and improving treatments by leveraging large-scale data resources and fostering cross-sector collaboration." According to HHS, the NIH plans to explore partnerships with federal agencies like the Centers for Medicare and Medicaid Services to create a "comprehensive real-world health dataset" while maintaining "the highest standards of security and patient privacy." The NIH has described this as a "secure data repository" to analyze de-identified data, similar to their existing cancer database, emphasizing that "these efforts are not about tracking individuals."

We have a lot of questions and not a lot of answers at this point. We'll continue monitoring these developments to ensure that the research respects both scientific integrity and the dignity of autistic individuals, particularly in light of the Secretary's concerning characterization of autism as a "preventable disease."

Can RFK Jr. Find "The Cause" of Autism by September?

In short: No. (We’ve shared our thoughts on this in a previous newsletter).

RFK Jr. has described autism as a "preventable disease" caused by environmental exposure and pledged to identify its cause by the fall. This represents a fundamental misunderstanding of what decades of research has taught us.

The scientific consensus is that autism is a complex neurodevelopmental condition with multiple contributing factors, with genetics playing a major role. Despite extensive research spanning decades, no single clear cause has been identified—and for good reason. The reality is likely a complex interplay of genetic predisposition and various biological factors, with most brain differences developing during early prenatal development.

One thing is crystal clear: there is no link between vaccines and autism. This question has been extensively studied and definitively answered.

Looking Forward: What Really Matters

As we process these new numbers, it's worth reflecting on what our society's response should be. The increasing identification of autism isn't inherently negative—it means more people are receiving diagnoses that can help them access appropriate support and resources.

Scientific research clearly shows that autism has strong genetic foundations. The brain differences associated with autism typically develop in utero during the first trimester—long before external interventions like vaccines occur. Any comprehensive understanding of autism must begin with this biological reality.

Rather than treating autism as something to be "cured" or prevented, we should focus on creating a more inclusive society where neurodivergent individuals can thrive. This means addressing concrete challenges through:

• Educational supports tailored to diverse learning styles

• Employment initiatives that recognize autistic talents and accommodate differences

• Healthcare that respects autistic experiences rather than pathologizing them

• Community resources that support autistic individuals across their lifespan

• Research that prioritizes quality of life improvements over finding a singular "cause"

The real headline shouldn't be about rising numbers—it should be about whether we're rising to meet the needs of autistic individuals and their families. Are we building systems that recognize, respect, and support different ways of thinking and being in the world?

That's the conversation we should be having. And as many autistic self-advocates remind us, autism is not damage or disease—it's a fundamental aspect of human neurodiversity that brings both challenges and unique strengths to our collective experience.

Stay Curious,

Unbiased Science

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