Health authorities are locked in crisis talks debating a snap five-day lockdown for Melbourne in a desperate battle to stop the coronavirus cluster from spreading.

The city’s fate hangs in the balance after six new cases were announced on Wednesday as the outbreak grew to 15. 

It’s understood officials are considering a five day circuit breaker, which could be extended if significant numbers of cases not directly linked to the current cluster emerge.

Sources claim the decision could go either way, the<a style="font-weight: bold;" class="class" rel="nofollow noreferrer noopener" target="_blank" website Herald Sun reported.

The crisis talks come hours after Acting Victorian Premier James Merlino revealed the next 24 hours will be critical to avoiding a second snap lockdown within four months.

Premier Daniel Andrews is understood to be monitoring the situation closely while on leave with a back injury while officials believe the 15 cases are closely linked.

South Australia has slammed shut its borders to Melbourne in the wake of the growing outbreak.

Melbourne's fate hangs in the balance with a snap lockdown being considered. Pictured are queues at a testing facility in Melbourne on Wednesday

Melbourne's fate hangs in the balance with a snap lockdown being considered. Pictured are queues at a testing facility in Melbourne on Wednesday

Melbourne’s fate hangs in the balance with a snap lockdown being considered.

Pictured are queues at a testing facility in Melbourne on Wednesday

South Australian Premier Steven Marshall declared anyone from Greater Melbourne is banned from entering the state from 6pm Wednesday.

Essential workers and returning South Australians will be allowed to cross the border but they must get three virus tests and isolate for 14 days.

Travellers who have crossed the border from Greater Melbourne from May 20  have also been ordered to undergo testing and isolate until they return a negative result.

‘Our thoughts are with everybody in Melbourne.

Any outbreak is something we need to take extraordinarily serious,’ Mr Marshall said.

South Australia’s Chief Public Health Officer Nicola Spurrier is concerned about the growing number of exposure sites across Melbourne and and regional Victoria.

She said three South Australians have been identified as close contacts of a confirmed case in someone who attended the Port Adelaide and Collingwood AFL game at the MCG on Sunday.

They have been asked to isolate, with one of those three still in Melbourne. 

Almost 500 other South Australians who also attended the game are being considered to be tier 2 contacts and will be ordered to get tested.

Of 30,000 texts sent to South Australians who have visited Victoria since May 6, 44 admitted to SA Health they’ve been to high-risk exposure sites.

Road checkpoints have also been reintroduced at the borders.

‘The snap border closure does not allow enough time for motorists to flee to SA from Victoria,’ SA Police Commissioner Grant Stevens said.

‘There is no reason anyone could be making a run for the border at this point,’

Melbourne is on high alert with 15 Covid cases recorded since Monday. Pictured is a health worker at a South Melbourne drive-through testing site

Melbourne is on high alert with 15 Covid cases recorded since Monday. Pictured is a health worker at a South Melbourne drive-through testing site

Melbourne is on high alert with 15 Covid cases recorded since Monday.

Pictured is a health worker at a South Melbourne drive-through testing site

Melburnians have been banned from crossing the South Australian border. Pictured is a testing queue on Wednesday

Melburnians have been banned from crossing the South Australian border. Pictured is a testing queue on Wednesday

Melburnians have been banned from crossing the South Australian border.

Pictured is a testing queue on Wednesday

Victorian health officials are concerned about the the growing list of exposure sites and the type of venues involved, including bars, nightclubs, the MCG and Marvel Stadium.

Of biggest concern on the list is trendy nightspot Somewhere Bar in Prahran.

It’s understood a group of revellers entered the bar late Saturday night without having to check-in. Herald Sun reported.

It’s since emerged an infected case was at the venue at the time.

Anyone who attended Somewhere Bar between 10.30pm and 1am and isolate for 14 days, regardless of the test result.

A shopping centre in Melbourne’s inner north is also the latest in a string of venues to be exposed to Covid. 

Barkly Square in Brunswick, in Melbourne’s north was added to the list of Tier 2 exposure sites after a Covid-positive shopper visited Priceline Pharmacy, OPSM, Kmart and Woolworths.

‘We have been advised the affected individual was present at the centre on Saturday, May 22 between 1:15pm and 2:30pm,’ centre management said in a statement.  

Anyone who attended the complex at the above times must get tested immediately and isolate until they receive a negative result.

All staff members who came into close contact with the positive case will isolate for 14 days, while a deep clean of the shops will begin, the centre said.  

Barkly Square in Brunswick, in Melbourne's north, was added to the list of Tier 2 exposure sites after a Covid-positive shopper visited Priceline Pharmacy, OPSM, Kmart and Woolworths

Barkly Square in Brunswick, in Melbourne's north, was added to the list of Tier 2 exposure sites after a Covid-positive shopper visited Priceline Pharmacy, OPSM, Kmart and Woolworths

Barkly Square in Brunswick, in Melbourne’s north, sbobet mobile was added to the list of Tier 2 exposure sites after a Covid-positive shopper visited Priceline Pharmacy, OPSM, Kmart and Woolworths

Melbourne's Covid outbreak is now at 15 cases, with 11 new infections - five of which were announced late on Tuesday

Melbourne's Covid outbreak is now at 15 cases, with 11 new infections - five of which were announced late on Tuesday

Melbourne’s Covid outbreak is now at 15 cases, with 11 new infections – five of which were announced late on Tuesday

The six new cases are close contacts of people who have already tested positive to Covid as part of the City of Whittlesea cluster, which has grown since Monday to 15.

Five of the six new cases are linked to a finance firm in Port Melbourne where one infected person works.

‘It’s good that everyone is linked at this stage but we are concerned about the number and also about the kind of exposure sites,’ Mr Merlino told reporters on Wednesday.

‘The next 24 hours are going to be critical.

‘I cannot rule out taking some further action but we’ll update people as soon as we know.’

All 15 cases have the B1617 COVD-19 variant, which originated in India late last year.

Genomic sequencing shows the outbreak is linked to the case of a Wollert man, who contracted the virus in SA quarantine earlier this month.

But a definitive link between the Wollert man and the outbreak hasn’t been established.

Acting Victorian Premier James Merlino says the next 24 hours will be critical to avoid another lockdown after the state recorded six more locally acquired COVID-19 cases

Acting Victorian Premier James Merlino says the next 24 hours will be critical to avoid another lockdown after the state recorded six more locally acquired COVID-19 cases

Acting Victorian Premier James Merlino says the next 24 hours will be critical to avoid another lockdown after the state recorded six more locally acquired COVID-19 cases

There are now more than 50 exposure sites across Melbourne and regional Victoria

There are now more than 50 exposure sites across Melbourne and regional Victoria

There are now more than 50 exposure sites across Melbourne and regional Victoria 

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