TORONTO -- Thousands more Ontario children with autism are on waiting lists for treatment than 10 years ago, and government figures suggest the number of kids receiving treatment may actually be dropping.

The NDP submitted a Freedom of Information request for the numbers of children with autism spectrum disorders on wait lists for Intensive Behavioural Intervention and Applied Behaviour Analysis and found dramatically increasing numbers.

In 2005-06, there were 753 kids waiting for IBI and now there are 2,192. In 2011-12, when ABA funding began, there were 2,784 kids on the wait list and now there are 13,966, though some children may be on both lists.

Kara Onofrio's seven-year-old son has been waiting for government-funded treatment for three years, and she has been told he will likely be on the wait list for another two. In the meantime, Onofrio has been paying $40,000 a year out of pocket to have her son in therapy part-time, she said.

"You feel like your child's not going to live a full life until you start to see the results from therapy," Onofrio said. "For my husband and I, $40,000 a year is worth it, but not a lot of families can do that and it's not fair that they have to suffer."

Onofrio, who also established Autism's Angels -- an organization that raises money for autism charities -- said the therapy Justin has received has been "life changing."

"I can't fathom where he would be if he didn't have that intervention early," she said. "It scares me."

Estimates from the Ministry of Children and Youth Services show that the wait lists are growing exponentially faster than the number of children receiving government-funded treatment.

Only five more children were expected to receive IBI treatment this year than last, an increase of just 61 more children since 2007-08. The number for ABA actually dropped from a high of 8,926 in 2013-13 to 8,000 this year -- though some children may receive more than one ABA treatment in a year.

Minister Tracy MacCharles said after question period she was "not entirely sure" about the decrease.

The government is constantly working to improve the services it provides and is investing more than $190 million in autism services this year, an increase of more than $100 million since 2004, MacCharles said.

But she couldn't point to what specifically the government would do to tackle the wait lists, saying it would be part of an autism strategy based on expert advice.

"We have new diagnostic tools, which may be contributing to the upward climb," she said. "The reality is the numbers on the wait lists are too high. I would totally agree with that. It's a huge area of focus for me."