In comparison, 98 percent of typical people and 91 percent of people with disabilities in general find paying work in that time frame."The autism number is quite a bit lower than that, and that's the concern," Roux said.
"You can see that they struggle a lot early on." About half are not connected either to school or to work within two years of leaving high school.
ASD is an umbrella diagnosis in the DSM-5, replacing the four pervasive developmental disorders described in the previous edition — autistic disorder, Asperger's syndrome, childhood disintegrative disorder, and pervasive developmental disorder not otherwise specified.
Individuals display ASD symptoms on a continuum, or spectrum, showing ranges of mild to severe symptomatology.
No two people with autism are alike, but many parents notice signs of the disorder when their child does not meet certain developmental milestones, typically between 18 months and 3 years of age.
For instance, the child may have problems with eye contact, responding to his or her name or engaging in imaginative play.
"Sometimes the parents think these are substitutes and they choose not to put their children in behavioral treatments," Elsabbagh said.
"And that takes away every chance the child could have to have a more validated option." Most autism research focuses on children, but more researchers are beginning to examine how the disorder affects the lives of adults.
People with certain genetic disorders, such as fragile X syndrome, tuberous sclerosis complex and Angelman syndrome, also tend to have autism, experts say. However, there are behavioral and educational therapies that may help reduce symptoms.
And early diagnosis is key to connecting children with autism to treatment, Elsabbagh said.