Melbourne will stay in lockdown for a further seven days as health officials remain concerned about a coronavirus variant that is "quicker and more contagious than we've ever seen before".
Acting Victorian Premier James Merlino announced the lockdown extension for Melbourne on Wednesday, but said some restrictions would be eased for regional Victoria.
Six new locally transmitted infections were recorded on Wednesday from just over 51,000 tests, including a positive case who had recently travelled to New South Wales. The total number of cases linked to the current outbreak is now 60.
Later on Wednesday afternoon, , in Melbourne's west. This case will likely be included in Thursday's numbers.
"If we let this thing run its course, it will explode," Mr Merlino said. "We have to run this to ground, because if we don't, people will die."
Residents of Metropolitan Melbourne will remain under lockdown until 11.59pm, 10 June, with five exceptions - to buy essential supplies, for approved work, to give or receive care, exercise, and to be vaccinated.
In Melbourne, from midnight on 3 June, the travel restriction for approved activities will be expanded from five kilometres to 10 kilometres - and year 11 and 12 students will return to in-class learning.
At the same time, the stay-at-home orders will be lifted for regional Victoria and there will be no limit on the distance residents can travel from their home. Gathering limits will remain, however, with groups of up to 10 people permitted to meet outside.
Regional Victorians will only be able to travel to Melbourne for the five permitted reasons and must follow the harsher restrictions while there.
Food, entertainment, retail, and religious services will also be able to open in regional areas, but businesses will be required to confirm that patrons are not residents of Melbourne.
"We've also seen previous examples of people who left Melbourne, broke the rules and took the virus with them," Mr Merlino said. "We do not want to see that happen again, particularly with this variant of concern that is this outbreak."
The decision to extend the lockdown was made after an increase in casual contact transmission, with at least one-in-10 current cases infected by a stranger.
There has also been an increase in cases linked to outdoor sites, where transmission would previously have not been expected.
"That's not something that we routinely see and we didn't routinely see it in 2020," Chief Medical Officer Brett Sutton said.
"We can't let it get away. We can't go to settings where it would move unchecked with huge numbers of people exposed."
There are now more than 350 exposure sites across the state and more than 5,200 primary close contacts, with 78 per cent of those returning a negative test.
Wednesday's cases include a person who has a home in Anglesea on the Great Ocean Road and his family, leading to a number of possible exposure sites in the area. It is still unclear how the family contracted the virus.
The second positive case at Arcare Maidstone, revealed later on Wednesday afternoon, comes after one resident and two staff members tested positive earlier this week.
COVID-19 testing commander Jeroen Weimar previously said there were four to five instances in the state's latest outbreak of people contracting the virus from "fleeting contact".
"They do not know each other's names and that is very different from what we have seen before," Mr Weimar told reporters on Tuesday.
The concerning spread of a variant, first detected in India, has also prompted authorities to encourage visitors to 14 shopping hubs across Melbourne over the past two weeks to come forward for testing.
It comes as at 10 vaccination centres across the state from Wednesday as part of a five-day jab blitz.
Express lanes exclusively for aged care and disability staff will open from 9am to 4pm, with workers needing to show proof of employment.
It follows the three-case Arcare Maidstone outbreak, now genomically linked to a South Australian hotel quarantine leak, exposing gaps in private aged care vaccinations among workers and residents.
In Senate estimates on Tuesday, it emerged that less than 10 per cent of nursing home staff across Australia have been vaccinated through federal government visits.
With AAP