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Autism Spectrum Disorder: What You Need to Know

Autism is a condition that people talk about a lot but is often misunderstood. Part of that might be due to how wide-ranging the effects can be; autism’s effect on the brain can be mild, severe or somewhere in between.

Autism spectrum disorder (ASD) refers to this group of developmental disorders that can cause social, communication and behavioral challenges.

The spectrum includes conditions doctors used to refer to individually, such as Asperger’s syndrome, autistic disorder or nonspecific pervasive developmental disorder.

While there is no cure, intensive, early intervention during the preschool years may lessen the long-term impact of the disorder.

There Is No “One Autism”

“The easiest way to think of autism is that it’s a constellation of behavior features that tend to travel together,” says UNC Health child and adolescent psychiatrist Robert B. Christian, MD.

An individual with ASD might repeat actions over and over, have especially intense and narrow interests, and might have trouble communicating with and relating to others. Children with autism might struggle to make eye contact; some with ASD find certain sounds, smells and types of touch overwhelming or uncomfortable.

The level of severity and the specific behavior patterns are unique to an individual. There is no “one autism,” Dr. Christian says.

Some children with this disorder have trouble learning, while others learn quickly but struggle socially. And while some signs of ASD are subtle, typically they present early—signs are usually seen by the age of 2—and last throughout a person’s life.

People with ASD interact differently with the world around them, Dr. Christian says. Some people will need significant help to function in their daily lives.

“That’s why it’s important to learn the signs and act early,” he says.

Autism Prevalence and Risk Factors

ASD affects about 1 in 54 children in the United States, according to the Centers for Disease Control and Prevention, based on 2016 numbers.

That estimate represents a 10 percent increase from two years earlier, and a 175 percent increase since 2002.

So is ASD increasing, or are doctors just getting better at detecting and reporting it?

“We don’t know for sure,” Dr. Christian says. “There is an increasing recognition of the signs, some evolution in the definition and improved record keeping,” he says.

ASD is a complex condition with no single known cause, but experts believe both genetics and environment can play a role. Risk factors include a family history of the disorder and being male—ASD is about four times more common among boys than girls.

While the latest research suggests a strong genetic link for ASD, more is needed to understand what causes the disorder, Dr. Christian says.

One thing scientists do know for sure: Vaccines do not cause autism.

Signs a Child Should be Evaluated for Autism

Babies and toddlers develop at their own pace. Your pediatrician will be on the lookout for signs of developmental delays during regular checkups; if your child shows signs of ASD, he or she will likely be referred for further testing by a specialist.

“Some signs of ASD can be subtle but they present early,” Dr. Christian says.

The following are some behaviors the CDC considers possible “red flags”—behavior that could indicate that your child has ASD. (Of course, individuals may display these behaviors and not have ASD.)

  • Fails to respond to his or her name by 12 months of age
  • Doesn’t want to play “make-believe” by 18 months of age
  • Prefers time alone and avoids eye contact
  • Doesn’t seem to relate to other people’s feelings
  • Is prone to repeating words and phrases in an obsessive manner
  • Gets easily rattled with minor changes
  • Performs repetitive movements, such as hand flapping or rocking

Discuss any concerns you might have with your child’s pediatrician.

How Autism Is Diagnosed 

In most cases, diagnosing ASD is a two-step process. First, your child’s pediatrician will look for signs of developmental delays during normal checkups.

More formally, the American Academy of Pediatrics recommends screening all children for ASD at ages 18 and 24 months.

Children who show signs of developmental delay are referred to specialists—a child psychiatrist or psychologist, pediatric neurologist or developmental pediatrician—for a more thorough evaluation.

Early intervention can help improve a child’s IQ, language and everyday functioning skills, Dr. Christian says. Speech therapy, physical therapy and occupational therapy can play a major role in helping the child learn to talk, walk and perform daily tasks.

There are helpful behavioral therapies available, including applied behavior analysis (ABA), which uses strategies to encourage positive behaviors and discourage negative behaviors while improving the child’s skills.

Today, the average age of diagnosis is about 4 years old; Dr. Christian and other autism experts would like to see children with ASD diagnosed much earlier, ideally before the age of 2.

Parents who are concerned that their child might have ASD should speak to their child’s pediatrician, Dr. Christian says, “the earlier, the better.”


Talk to your pediatrician about scheduling a screening for your child. Need a pediatrician or a pediatric specialist? Find one near you.