Victoria recorded 423 new, locally-acquired COVID cases and two deaths on Wednesday, as Ballarat was ordered back into lockdown from midnight tonight following a number of new cases in the area.
Meanwhile, Shepparton will join the rest of regional Victoria from midnight after recording no new cases for three days running.
Today's announcement comes after two new cases were recorded in Ballarat, in addition to two authorised workers who had previously tested positive to the virus.
Victorian Premier Daniel Andrews said cases in the area were expected to increase in the coming days, with a number of wastewater detections also recorded.
A positive detection from September 8 remains of particular concern to health authorities, who fear it means there's been over a week of likely transmission within the Ballarat community.
"We've had a number of wastewater detections in Ballarat, so from 11.59pm tonight the city of Ballarat has to go into a lockdown for seven days," he said.
"This is not the news the people of Ballarat want to hear and it's not the decision we wanted to make. But if we allow it to get away from us in one part of regional Victoria, it becomes a threat and a risk to all of regional Victoria. We simply can't have that happen.
"Shepparton shows you a community can be locked down, can stick together, can be supported and deliver fundamental control of an outbreak. We know, and we're very confident that's exactly what can happen in the Ballarat community."
He said there was no other option in a greater effort to protect the freedoms of regional Victoria.
"The alternative is to let it run, and then we finish up in you know - we have no choice, but not today, but perhaps in a week's time, we have to close all of regional Victoria because cases have got away from us and there are patterns of movement," he said.
"Ballarat is not a community that is shut off from anyone else. People move to different parts of regional Victoria, they move to Melbourne, those patterns of movement mean the virus could hitch a ride and if unchecked spread right through regional Victoria and compromise the very low numbers of cases in regional Victoria right now."
He said additional vaccines would now be fast-tracked to the Ballarat area.
"They're right on the 70 per cent single dose already. We want to use this seven-day period to vaccinate as many people we can beyond that."
A number of exposure sites in Ballarat have been added by the Department of Health, including the Lake View Hotel on September 9 between 7.15am and 7.55am and September 10 between 9.45am and 11.30am.
A Big W in Ballarat was also listed for the 10th, as was Forge Pizzeria on the 11th, from 2.50 to 3.30 in the afternoon.
Of today's 423 new cases, 88 per cent were in the northern and western suburbs.
- 270 positive cases in the northern suburbs including locations such as Craigieburn, Roxburgh Park, and Glenroy.
- 112 in western suburbs such as Truganina, Tarneit and Point Cook.
- 10 in the eastern suburbs, across Croydon and Donvale.
- 25 in the south-east in Keysborough, Dandenong, and Clyde North.
- Five regional cases - two in Ballarat, one in Geelong, two in Mitchell Shire.
The new figures bring the total number of active coronavirus cases in the state to 4038 - 84 per cent of those are under the age of 50, and one quarter are in their 20s.
There are 173 Victorians currently in hospital with COVID, 44 of which are in intensive care and 23 are on a ventilator.
Sadly, another two deaths were recorded overnight, including a man in his 40s from the Whittlesea area and a second man in his 70s from Wyndham.
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