Children should be screened for autism twice by the time they are two years old to look for symptoms such as babies who don't babble at nine months and one-year-olds who don't point to toys.

That's the advice from the American Academy of Pediatrics in two reports the group presented at its annual meeting in San Francisco Monday.

The advice is meant to help both parents and doctors spot autism sooner so that therapy can begin as soon as possible. While there is no cure for autism, experts say early therapy can lessen its severity.

The reports list numerous warning signs that are absolute indications for immediate evaluation. They include:

• no babbling or pointing or other gesture by 12 months;
• no single words by 16 months;
• no two-word spontaneous phrases by 24 months;
• loss of language or social skills at any age.

Earlier, subtle signs that that could lead to earlier diagnosis include:

• not turning when the parent says the baby's name;
• not turning to look when the parent points says, "Look at..." and not pointing themselves to show parents an interesting object or event;
• lack of back and forth babbling;
• smiling late; and
• failure to make eye contact with people.

The doctors also want to warn parents that not all children who display a few of the symptoms are autistic. They note that just because a child likes to line up toy cars or likes to repeatedly stroke a favourite stuffed animal doesn't mean they have the developmental disorder - especially if they're also interacting socially and also communicating well.

The American Academy of Pediatrics first issued guidelines about autism in 2001. A 2006 policy statement urged autism screening for all children at their regular doctor visits at age 18 months and 24 months.

The new reports advise intervention as soon as an autism diagnosis is seriously considered, rather than deferring until a definitive diagnosis is made.

Recommended treatment should include at least 25 hours a week of intensive behavior-based therapy, including educational activities and speech therapy, according to the reports.

The Academy lists several specific approaches that have been shown to help. They also list many that have not, including special diets and alternative treatments endorsed by celebrities, saying there's no proof those work.

Meanwhile, Canadian pediatricians are applauding the recommendations.

"I think it is absolutely essential to be watching children for early signs of autism so I think it is an excellent recommendation," says Dr. Wendy Roberts, the director of the Child Development Centre at Toronto's Hospital for Sick Children. "we are trying to teach all family physicians and pediatricians to look very carefully for the early signs of autism."

But autism experts note that many parents in Canada are already waiting years for therapy. They say screening earlier will only uncover more children who will need treatment.

"What are we going to do with all these children?" wonders Dr. Derrick MacFabe, director of the Kilee Patchell-Evans Autism Research Group at the University of Western Ontario. "How are we going to help them?"

The Autism Society of Canada estimates that one in every 165 children is born with an Autism Spectrum Disorder and that there are approximately 200,000 Canadians living with an ASD.

The cause or causes of autism are still unknown. Many possible causes are being investigated, such as genetics, environmental factors, viral infections and immune responses and deficiencies.