There was a 126 per cent increase in people contacting the Victorian Mental Illness Awareness Council for support at the height of the pandemic, the organisation's chief executive Craig Wallace told a committee reviewing the state's pandemic orders.
Moving support online left vulnerable people more isolated and distressed, Mr Wallace said.
"The repeated use of phone and video was exhausting and became overwhelming, removing the desire and ability to continue to reach out for support," he said on Friday.
VMIAC developed the Check-In peer support program during the pandemic, as a way to connect disengaged vulnerable people with support workers who have a lived experience.
But funding for the program from the state government will be discontinued next month leaving its future uncertain, he told the inquiry.
"That's of great disappointment to us. I think the expectation is that we will be able to provide some of that through our core funding," Mr Wallace said.
"We have a difficult situation in the next six weeks of trying to work to ensure as much of that expertise is documented, so that it can be carried on by the organisation."
It's necessary to continue those support programs because the demand for help is still high, VMIAC's National Disability Insurance Scheme manager Neil Turton-Lane told the inquiry.
"COVID is like a slow train wreck that you're watching," he said.
"The pandemic is not over. Its effects have been felt very deeply at all levels of our community."
Children also had to deal with greater challenges during lockdowns, Shadow Pandemic Victoria co-founders Jacquie Blackwell and Moran Dvir told the inquiry.
The pair started their advocacy group last year to fight Victoria's lengthy school closures.
The government should not resort to school shutdowns again otherwise children's mental health will only deteriorate further, the group told the inquiry.
"We very firmly believe that it is not the job of children to keep adults safe," Ms Dvir said on Friday.
"The burden should not ever be on children and the burden has gone far and above keeping adults safe."
The inquiry continues.
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