Covid Victoria: 21 new cases as Australia's biggest mall exposed

Victoria has recorded 21 new locally acquired Covid-19 cases as Melbourne enters another weekend of lockdown.

The Department of Health revealed 10 of the cases were infectious in the community.

Promisingly, all of the cases are linked to previously reported cases. However in the three days prior, 13 mystery cases had emerged with health authorities scrambling to trace the virus.

Saturday's total is the fourth time in five days the daily total has been 20 or higher.

It comes as Australia's biggest mall, the Chadstone shopping centre in Melbourne, has been declared a COVID-19 exposure site.

Mystery cases continue to emerge in Melbourne. Source: Getty
Mystery cases continue to emerge in Melbourne. Source: Getty

The centre was declared a tier two site on Friday night.

Anyone who was at Chadstone between 4.26pm and 5.40pm on Saturday August 7 must take a COVID test and isolate until they receive a negative result.

The Coles supermarket within the shopping centre has also been listed.

There are now more than 450 exposure sites in Melbourne including Highpoint shopping centre and several large apartment blocks.

Expert believes lockdown will be extended

Professor Adrian Esterman, an epidemiologist and biostatistician at the University of South Australia, believes Melbourne will get on top of its Delta variant outbreaks, but not by August 19 when the lockdown is due to end.

"I would say it's highly unlikely," he told AAP.

"I don't think that lockdown will finish ... until you're in single digits and have no mystery cases."

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Unexpected wastewater detections have also arisen in the regional areas of Shepparton and Lakes Entrance, where there are no known active cases or current exposure sites.

Lockdown 'heartbreaking' for children

Victoria's Chief Health Officer Brett Sutton says the lockdown's ongoing toll on children is "heartbreaking", as mystery COVID-19 cases threaten to further extend the shutdown.

Professor Sutton said he considers the social impacts of lockdowns when providing health advice to the state government, including keeping children out of school and away from their friends.

"It's heartbreaking," he told 3AW of having to explain that fact to his own three young children.

"But, again, what alternative pathway have we got available to us? Because we know what happens when restrictions are not done in a timely way or are not sufficient to control transmission - it explodes in numbers."

Melbourne is in the second week of its sixth lockdown, brought on to contain several Delta variant outbreaks.

With AAP

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