AUTISM is a challenging neurobiological condition that can leave families feeling overwhelmed, isolated and hopeless. Contributing to these troubles is the fact that in about half of U.S. states — Washington included — state laws don’t require health-insurance coverage for autism treatments. For thousands of families whose insurance policies are regulated by Washington state, this means they face a critical gap in coverage for their loved one.

The impact of the lack of insurance coverage for autism treatments extends to all state taxpayers, who ultimately have to foot the bill for special education and lifelong care and support for people with autism who were not able to benefit from empirically supported treatments that have been shown to be effective for improving outcomes.

Neither families nor taxpayers win when a treatable condition — especially one as widespread as autism, which affects one in every 110 children and is the fastest-growing developmental disability in the country — is not covered by insurance.

Washington has about 12,000 children who have been diagnosed with autism, and the potential cost of untreated autism to taxpayers is considerable. It’s estimated that early diagnosis and intervention that are covered by insurance could save the state billions in lifetime costs for the current population of children with autism.

Studies show that requiring insurance companies to cover autism treatment would increase premiums by roughly one half of 1 percent — far less than the billions in savings that could be gained if people received treatment.

In South Carolina, where the legislation has been in effect for two full years, the premium impact has been reported as a mere 44 cents per member per month.

Most families simply can’t afford to treat their child’s autism without insurance coverage. Treatment, which often requires intensive one-on-one behavioral therapies, can cost as much as $50,000 per year. That means families are forced to watch their children suffer, with little or no ability to help them. or, they cobble together the treatments they can, taking out second mortgages or emptying siblings’ college funds.

There is no cure for autism, but studies show that behavioral and biomedical treatments can dramatically improve symptoms. With proper treatment, children can vastly increase language and communication skills and improve their quality of life. They can succeed at school, make friends and become participating members of their communities — even taxpayers.

The state Legislature is considering Senate bill 5059, also known as “Shayan’s Law,” which would require health-insurance coverage for thousands of Washington individuals diagnosed with autism. Only proven treatments will be covered, making sure that costs are contained.

Twenty-three states have already enacted autism-insurance reform, and many are currently pursuing passage. the choice for Washington legislators is clear: either save a generation of children today through a minimal increase in insurance premiums, or continue to burden taxpayers with millions of dollars in long-term costs of caring for untreated children.

The choice should be easy. the time is now to pass Shayan’s Law.

Geraldine Dawson is the chief science officer for Autism Speaks, a research professor of psychiatry at the University of North Carolina at Chapel Hill and professor emeritus at the University of Washington.