The Department of Health and Human Services has launched a “massive testing and research effort” that HHS Secretary Robert F. Kennedy Jr. said will determine the cause of rising childhood autism rates in the country. 

During a meeting of President Trump’s Cabinet on Thursday, Kennedy said the process will involve “hundreds of scientists around the world” and answers will come this fall. 

“By September we will know what has caused the autism epidemic,” Kennedy said. “And we’ll be able to eliminate those exposures.” 

Kennedy, a longtime vaccine critic who helped found one of the most prominent anti-vaccine organizations, has spent decades religiously promoting the theory that childhood vaccines have led to an increase in autism and chronic illnesses, despite studies repeatedly showing otherwise. 

The federal government spent more than $300 million on autism research in 2023, according to the most recent figure available. Former President Biden in January signed a five-year extension of the Autism CARES Act to authorize nearly $2 billion for autism research. 

Scientists don’t know exactly what causes autism spectrum disorder (ASD), but they are researching numerous environmental, genetic and biological possibilities including an infection or contact with chemicals in the environment, problems with brain connections, problems with metabolism and more. 

No reliable study has shown a link between autism spectrum disorder and any vaccine, but Trump on Thursday without any basis said autism could be caused by “something artificial” and “maybe it’s a shot.” 

“There will be no bigger news conference than that…,” Trump said. “If you can come up with that answer where you stop taking something, you stop eating something, or maybe it’s a shot. But something’s causing it.” 

Kennedy has reportedly hired David Geier, a longtime figure in the anti-vaccine movement who has spent years attempting to tie mercury in vaccines to autism, to lead the research effort.

In 2012, the state of Maryland found Geier was practicing medicine without a license.  

Trump and Kennedy have expressed concern about rising autism rates, but experts have attributed the increase to better awareness of symptoms in children and changing criteria to diagnose ASD in kids. 

About 1 in 36 children now have a diagnosis of ASD, according to estimates from the Centers for Disease Control and Prevention (CDC), compared to about 1 in 150 in 2000.