Closing entire industries and extending Melbourne’s six-week lockdown are some of the measures being considered as Victoria reported the highest one-day spike in COVID cases yet seen in Australia on Monday.

With 532 more cases and six deaths – five connected to aged-care facilities – Victoria’s chief health officer Brett Sutton said Monday’s numbers could be the peak of the state’s virus outbreak, but the days ahead would be most telling amid a worsening aged-care crisis.

Victoria has 4542 active coronavirus cases, with 245 people in hospital and 44 in intensive care. Monday’s deaths take the state’s toll to 77 and the national figure to 161.

“Modelling, with our effective reproduction number that I have seen most recently, suggests that today should be the peak,” Professor Sutton said.

“Now, I’m not going to sit back and say today is the peak. We have to see what happens in coming days.”

Almost three weeks into stage three lockdowns in greater Melbourne and the neighbouring Mitchell Shire, Victoria had 816 new cases at the weekend.

As of Monday, there were 683 active cases linked to aged-care facilities across Melbourne.

Threats of industries shutting down

Victoria’s record high daily case number prompted Premier Daniel Andrews to warn that if workplace transmission continued to rise, some industries would be forced to shut down.

“If we were to continue to see outbreaks, if we were to continue to see people quite obviously attending work when they shouldn’t be, then every option becomes on the table,” he said.

“The next steps may well have to include closing a number of these industries if we continue to see people attending work.”

Mr Andrews implored Victorians who had coronavirus symptoms not to go to work or there would be more deaths.

“Otherwise, these restrictions will be in place for longer than they should be, and I’m sorry to say, we will see more people die, particularly in aged care,” he said.

“If people are going to work sick, people will become infected. And therefore, people will die.”

“You simply can’t go to work if you have symptoms. You can’t go to work if you feel sick, even mildly,” he said.

“This is the biggest driver, it’s not the only issue, but it is the biggest driver of transmission.”

Mr Andrews said Monday’s six deaths included women in their 70s, 80s and 90s and men in their 50s, 70s and 80s. Five were connected to outbreaks in aged care.

Aged-care sector goes into damage control

Professor Sutton remains disturbed about outbreaks at aged-care homes, while the federal government has set up a call centre to help families of hundreds of affected residents to check on loved ones.

“These are very challenging numbers. We’re at a very challenging stage with this wave,” he said.

From Monday, responsibility for the sector’s response to COVID will be held by the Victorian Aged Care Response Centre, co-ordinating work of federal and state government organisations, as well as the defence force and emergency management groups.

The cases linked to aged-care centres are:

• St Basil’s Home for The Aged in Fawkner – 84
• Estia aged care in Ardeer – 82
• Epping Gardens Aged Care in Epping – 77
• Menarock Life aged care in Essendon – 62
• Glendale Aged Care in Werribee – 53
• Kirkbrae Presbyterian homes in Kilsyth – 57
• Estia aged care in Heidelberg – 50

There are also single cases in staff members at a host of other aged-care homes. They are: St Andrews Aged Care in Sunshine, Mercy Place Wyndham Aged Care Facility in Werribee, Mercy Place Keon Park Aged Care in Reservoir, VMCH Corpus Christi Aged Care in Clayton, VMCH Aged Care in Berwick, Cumberland Manor Aged Care Facility in Sunshine North, Uniting AgeWell in Box Hill and Japara Bayview Aged Care in Carrum Downs.

Federal Aged Care Minister Richard Colbeck said the Morrison government considered such homes “the biggest risk” in the current outbreak – and there were “a number of facilities we are extremely concerned about”.

Mr Colbeck told ABC radio the situation “will be very, very tragic”, citing a “very high” fatality rate for older Australians.

“There is a lot of bad news to come,” he said.

PM says all options should be on the table

Prime Minster Scott Morrison said it would take the efforts of the entire state to drive down Victoria’s case numbers.

He said calls about even harsher lockdowns were premature, but it was important to keep all options open.

“In Victoria, there is still a long way to go. We are still seeing case numbers at elevated levels and so, as we have seen from other jurisdictions, when you get community-based transmission, it does take some time to get that down,” Mr Morrison said.

He defended the government’s approach on supply and training of PPE, saying aged-care workers had been trained in infection control and using equipment.

“We’ve been taking action on this for weeks,” he said in Sydney.

Deputy chief medical officer Nick Coatsworth also said it would be some time before new infections flattened in parts of Victoria. where the virus had become “embedded” in the community.

“There will be light at the end of the tunnel. But those day-on-day numbers now are still concerning,” he told the ABC.