Health and Human Services Secretary Robert F. Kennedy Jr. on Wednesday said the U.S. is experiencing an "autism epidemic" that he claims cannot be explained by "better diagnostic criteria" or "genes."

The Centers for Disease Control and Prevention's latest Autism and Developmental Disabilities Monitoring Network survey, which was released as part of the CDC's Morbidity and Mortality Weekly Report, shows the prevalence of autism in the country has risen from 1 in 36 children to 1 in 31 children, according to the most recent data.

"The autism epidemic is running rampant," Kennedy said in a press release. "One in 31 American children born in 2014 are disabled by autism. That's up significantly from two years earlier and nearly five times higher than when the CDC first started running autism surveys in children born in 1992. Prevalence for boys is an astounding 1 in 20, and in California it's 1 in 12.5."

Kennedy, in a press conference Wednesday, called autism a "preventable disease" and claimed that "environmental exposure … has to be" the cause for the increase in diagnoses.

The CDC study counters him, noting that "research has not demonstrated that living in certain communities puts children at greater risk for developing [autism spectrum disorder]. Differences in the prevalence of children identified with ASD across communities might be due to differences in availability of services for early detection and evaluation and diagnostic practices."

The secretary called these explanations "epidemic denial," saying, "One of the things that I think we need to move away from today is this ideology that the autism prevalence increases, the relentless increases, are simply artifacts of better diagnoses, better recognition or changing diagnostic criteria."

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