Another 13 cases of coronavirus have been recorded at a Victorian abattoir, bringing the cluster's total to 62.
But Premier Daniel Andrews has hosed down any concerns about his government's handling of the outbreak at Cedar Meats in Melbourne's west.
"This has been a model example ... of dealing with an outbreak," he told reporters on Thursday.
The fresh cases at the facility include seven infected workers and six of their close contacts.
They are among 14 new infections in Victoria on Thursday, bringing the state's total to 1454.
Mr Andrews said the new cases at Cedar Meats demonstrate just how contagious the illness is.
"That's the nature of outbreaks. This is a very infectious disease, it spreads rapidly," he told reporters.
An abattoir worker tested positive to COVID-19 on April 2, but the workplace wasn't regarded as an exposure site because the employee had told health officials they hadn't been at work for weeks.
The second case linked to the workplace was diagnosed on April 24, followed by a third case about 24 hours later.
The department took further actions, including closing the site, on April 29.
Andrews defends investigation of first case
Mr Andrews said health officials were right not to question the account given by the worker who tested positive on April 2.
"If you say I have not been at work for four weeks, then we take you on face value," he said.
"If you looked where people said they hadn't been, well that wouldn't have any sense and we could never have enough staff to do it."
He noted Australia's Chief Medical Officer Brendan Murphy had commended the state government's handling of the outbreak at a meeting earlier in the week.
"I am very confident that everything that can be done is being done by a dedicated team of contact tracers," he said.
Mr Andrews went as far as to say some of Victoria’s contact tracers were “some of the best in the world”.
The meat facility outbreak has rocked Victoria ahead of a national cabinet expected to outline a relaxation on coronavirus restrictions.
Hospital worker didn’t wear PPE when treating first case
Among those infected is a healthcare worker at Sunshine Hospital, who was exposed to a Cedar Meats employee who came in after cutting their hand at work and before they later tested positive to the virus on April 26.
The Sunshine Hospital nurse in her 60s treated the worker over three shifts and was not required to wear protective equipment until the third instance, The Australian reports.
Another 24 workers at the hospital remain in quarantine.
A worker at Doutta Galla Aged Care in Footscray who was in close contact with an abattoir worker was also confirmed as positive on Wednesday.
The home is now closed to all visitation until at least May 11.
Meanwhile, a worker at Grant Lodge aged care in Bacchus Marsh tested positive on Saturday.
It's not believed to be connected to the Cedar Meats outbreak.
Federal Agriculture Minister David Littleproud has taken issue with his department not being notified of the Cedar Meats cases until April 30, despite permanent meat inspectors and those that move between abattoirs being on site in March and April.
He says Victorian officials should have told his department as soon as they knew, but stressed he was "not looking for any recriminations".
Authorities are still unsure how the Cedar Meats outbreak emerged.
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