Teachers, in addition to education support staff, administration staff and cleaners will have to have received their first jab by mid-October and be fully vaccinated by November 29 before they will be allowed to attend a school site.

Mandatory vaccinations for workers in aged-care, healthcare, quarantine and construction workers have already been introduced.

Victorian Deputy Premier James Merlino also announced an 'unprecedented package' which would see funds go to government and low-fee catholic and independent schools to conduct infrastructure audits, ventilation assessments and CO2 monitoring in classrooms ahead of schools re-opening.

"There are things that we can do to mitigate the risk to lower the risk of airborne transmission and today I am announcing a $190 million package of initiatives to ensure that when schools open, they stay open," Mr Merlino said.

"In an Australian first, we will have the biggest ever investment in ventilation in schools. We have signed a contract with Samsung and out of that $190 million, $125 million will deliver 50,000 air purification devices to every single government school and all low fee Catholic and Independent schools in Victoria."

The Government is also awaiting approval from the Therapeutic Goods Administration on a home-based trial and the use of rapid antigen testing.

Meanwhile, Ballarat will be released from lockdown at midnight tonight.

Mr Merlino applauded the city's residents.

"I am pleased to announce that the city of Ballarat will end its seven-day lockdown at night tonight," he said.

"The public health team feel they have deep outbreak contained and thanks to the extraordinary efforts of the residency came out in droves to get tested and followed lockdown rules. My thanks to the entire community of Ballarat.

"The five reasons to leave home will no longer apply and the setting in Ballarat will align with those of regional Victoria not in lockdown however there is still public health restrictions in place, masks must still be worn indoors and outdoors. No-one can come to your home to visit."

It comes as the state recorded the most daily COVID cases in over a year on Wednesday, with 628 new infections in the 24 hours until midnight, off the back of 60,829 test results received.

Sadly, three COVID-positive Victorians died overnight - a woman in her 50s from Wyndham, a man in his 70s from Wyndham and a man in his 80s from Darebin.

There are now 257 people in hospital with COVID, 58 are in ICU and 37 are on ventilators.

Of the cases who are in hospital yesterday, 81 per cent were not vaccinated, 15 per cent were partially vaccinated and 3 per cent were fully vaccinated.

There are now 6223 active cases of coronavirus across Victoria.

There are no new cases linked to a construction site in Hamilton.

Hamilton exposure sites as of Wednesday, September 22:

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