"Autistic individuals do not like sudden changes, sudden changes cause us incredible amounts of stress, and may create challenging behaviours, anxiety, and an increase in sensory overloads. This affects our families hugely. Many families have been on waiting lists for 18 months or more and now sit in limbo over who will take over.
She agreed more Government funding for autism services was needed.
"Autistic individuals are increasingly getting diagnosed due to better awareness but we believe that government has not matched funding for ASD services to meet the actual needs of the Autistic individuals diagnosed. If there is not sufficient funding autistics will continue to end up in autistic crisis."
IHC chief executive Ralph Jones said the situation was devastating.
"Families living with Autism are desperate for these services - and we have a waiting list," Jones said.
"We have indicated for months that we couldn't continue without a funding increase. We have put the time, money and the influence of IHC behind this to try to make the contract sustainable but it just doesn't work."
Autism New Zealand chief executive Dane Dougan said its branches had fielded a number of phone calls from families concerned about what would happen both in the short and long term.
Autism New Zealand offered some education programmes but spaces and funding were limited, he said.
"The funding we do receive hasn't really increased but the compliance has. It's very tight out there ... we're all in the same boat."
Ministry of Health disability support services group manager Toni Atkinson said the ministry had worked with Idea Services to try to ensure continuity.
They would continue to work together to support families while alternative services were arranged, he said.
"Idea have been funded at $2.3 million per annum to deliver these ASD services. They, like other providers, need to configure their service within the available funding," he said.
Other providers had already indicated a willingness to take on the contract but nothing had been confirmed.
There were 446 active clients and 728 families on the waiting list for ASD support and those people would remain top priority when a new service was established, he said.
The programmes that were cut:
• Growing up with Autism - designed to increase parental knowledge and skill in supporting their adolescent with autism
• ASD Plus - Increasing parental knowledge and skill in supporting their pre-school child with autism
• Communication & Behaviour - Improving the social, communication and coping skills of children or young people who have Autism Spectrum Disorder