California shattered yet another autism record during the first quarter of this year, a disturbing trend that increases the pressure to unlock the mysteries surrounding the disorder, officials said.

From January through March, 812 autistic children registered to receive care from the state Department of Developmental Services' regional centers.

That's the largest quarterly increase in state history, and it represents nine new children a day, seven days a week.

"We are extremely concerned about what these numbers mean," said Bob Baldo, executive director of the Association of Regional Center Agencies.

"This has the potential to financially almost break the system -- let alone the human costs," Baldo added. "The human costs are absolutely profound. This state can hardly afford to have this continue to go on."

Autism is a severe developmental disorder that undermines a child's ability to connect to the world. Autistic children often have difficulty making eye contact and carrying on a conversation. Many engage in ritualistic behavior such as hand-flapping and following routines.

There is no known cause and no cure.

Autism advocate Rick Rollens testified before Congress three years ago that the number of new autistic children entering the California system equaled five per day.

Now it's nine, and the increase shows no sign of abating.

"This is a terribly alarming trend and one that really needs the attention of the entire health community," said Rollens, the father of an autistic boy and a co-founder of the Medical Investigation of Neurodevelopmental Disorders Institute at UC Davis.

The latest statistics, which include only full-blown cases of autism, bring the total number of autistic people registered at regional centers in California to 17,614. This doesn't include the hundreds of children with milder forms of the disorder such as Asperger's syndrome and pervasive developmental disorders.

If the first-quarter pace continues, California would see a 19 percent jump in autism this year.

Some experts say there is no cause for concern. They blame the increase on greater familiarity with the disorder, better diagnosis and a broadening of the definition of autism.

But others note that if such factors are the only cause of the rapid rise, it should reach a plateau at some point. The latest statistics reveal this hasn't happened yet.

Many parents and some experts fear that an environmental factor -- such as a toxin or a bad reaction to a vaccine -- could be triggering autism in genetically vulnerable children.

Researchers at the UC Davis' institute are among the scientists scrambling for answers. They have a study under way to determine how much of the increase can be attributed to changes in definitions and diagnoses. Their conclusions are to be released this year.

Autistic children often require intensive and costly services, Baldo noted. Some advocates estimate it costs taxpayers more than $1 million for a lifetime of care for each autistic child.

"If there's a way to prevent this from occurring, we need to find out awful fast," Baldo said. "For everybody's sake, we need to get to the bottom of this. Every day that we delay, that means more and more damaged children."