Swedish climate activist Greta Thunberg, 20, is open about her autism. Actor Anthony Hopkins, 85, disclosed his diagnosis in 2017. And former New York assemblywoman Yuh-Line Niou, 39, the first known autistic woman elected to a state legislature, was diagnosed at the age of 22.

According to a new meta-study in JAMA Network, autism spectrum disorder (ASD) affects around 2.3% of Americans (more men than women), and presents with a range of abilities and disabilities.

Common early signs and symptoms of ASD appear in the first two years of life; they include a lack of response when a child's name is called, limited use of gestures in communication, and lack of imaginative play. Intensive interventions with children under age 5 can improve language, play, and social communication significantly.

The causes of ASD are uncertain, but there is some indication that it arises from a blend of genetic predispositions and environmental influences, including possible exposure in utero to certain infections or medications, as well as to chemical toxins found in air pollution and pesticides.

Unfortunately, there is no simple test to diagnose ASD. But if you suspect your child may have neurodevelopmental challenges or is on the spectrum, Autism Speaks has an online, 20-question screening tool that you can fill out and take to your pediatrician for further diagnostic steps.