‘Completely avoidable’: Andrews slams ‘thousands’ of partygoers behind huge Covid spike

• Victoria's coronavirus cases increase by nearly 500

• Covid-19 Cases 'caused by AFL Grand Final parties'

A furious Victorian Premier Daniel Andrews has fronted the media decrying the state's new Covid-19 cases as "completely avoidable" after most cases emerged from AFL Grand Final weekend.

The state's case jumped by nearly 500 in the past 24 hours after Victoria recorded 1438 new infections on Thursday.

Mr Andrews said contact tracers have determined through interviews "plenty of these cases were completely avoidable".

"Actual interviews tell us that many hundreds of people, perhaps thousands of people indeed, have made some choices that meant they're time not in their own home, but in someone else's home, and that's how we know this virus spreads," he said.

He added the number of new cases was "of great concern".

"This is the reality every single Victorian, including the government, faces," Mr Andrews said.

"If people continue to visit each other in their homes they will bring the virus with them. And look, I don't think anyone who necessarily makes that choice thinks that they're going to be spreading the virus but that's the reality of this thing.

"And four or five days, the Thursday after a long weekend, and particularly what we know from interviews over recent days, many of these cases were completely avoidable. Now of course, they will add further pressure to our health system."

He added: "I know it's frustrating".

Covid-19 cases 'caused by AFL Grand Final parties'

Covid Commander Jeroen Weimar called it a "very challenging day" for Victoria's latest outbreak.

"The 50 per cent increase in numbers is down to a significant number of social gatherings over Friday and Saturday last weekend," Mr Weimar said.

"We've seen over the last few weeks ongoing transmission in households, between households.

"What is different about numbers today, the activity five or six days ago was quite different. The contact tracers tell us that there have been significant numbers of social gatherings on Friday and Saturday, over a long weekend. Grand final parties."

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Last Friday was a public holiday in Victoria for what is normally reserved for the AFL Grand Final parade. The decider was held in Perth this year though because of Covid but the state still held the public holiday before the Grand Final on Saturday evening.

Mr Weimar said about a third of Thursday's cases are linked to social gatherings.

"We've had the most activity on our roads over a three-day weekend of any lockdown weekend since the end of July," he said.

"We're seeing a shift in the age profile, so in today's cases, 55 per cent are men.

"It's quite a different profile to what we've seen for the rest of the outbreak. We're seeing a disproportionate increase in those aged between 20 and 29, and those aged 20 and 50."

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