Victoria again recorded the bulk of the national tally, with 532 out of 549 cases.

Another six people have died from the disease, five of which are connected to outbreaks in aged care and one was a man in his 50s.

There are 44 people in intensive care units in the state, and 245 people in hospital.

Aged care is again the focus of efforts to contain the virus, but Victoria's chief health officer Brett Sutton said it was "an inescapable fact" that they were at significant risk of dying.

So far 35 residents of aged care homes have died from the disease and there are 681 active cases of both staff and residents connected to 61 facilities.

Victorian Premier Daniel Andrews has urged people not to go to work if they are sick, after an increase in cases connected to people continuing to go to work after showing symptoms.

"Please, do something that will we'll all be so grateful for - act on your symptoms. Don't ignore them. Don't head to work," he said.

"My plea, my appeal, my request and our requirement is that no one go to work if they have symptoms. Any workplace. Any workplace at all. You have got to go and get tested and then you have to wait at home until you get the results of that test."

Mr Andrews also signalled particular industries could be shut down if cases continued to grow, after questions were asked about abattoirs and meatworks, where some of the largest clusters have been.

"That's not the advice I have at the moment, but 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.

"Next steps may well have to include closing a number of these industries if we continue to see people attending work."

Clusters connected to aged care facilities in the state are growing, with chief health officer Brett Sutton saying that community transmission between essential workers has spread to aged care workers.

The number of cases connected to St Basil's Home for the Aged in Fawkner has grown to 84, 82 at Estia Health in Ardeer, 77 at Epping Gardens Aged Care, 62 at Menarock in Essendon, 53 at Glendale Aged Care in Werribee, 57 at Kirkbrae Presbyterian Home in Kilsyth, and 50 at Estia Aged Care in Heidelberg.

"It's hard to read these out without considering the residents in these facilities will be people's parents, grandparents, great grandparents and they are at significant risk of dying," he said.

"That's an inescapable fact in these settings. Where there are outbreaks in aged care, the mortality is extremely high."

Professor Sutton remains disturbed about outbreaks at aged care facilities.

"These are very challenging numbers. We're at a very challenging stage with this wave," he told reporters.

The bulk of the 161 deaths in Australia have been people aged over 70, including 67 residents in aged care services.

"It is important to understand that the challenges - and they are significant in the aged care sector - are a reminder that when community transmission occurs with COVID-19, the aged care sector will all be impacted," Prime Minister Scott Morrison told reporters on Monday.

The federal government, which has responsibility for the sector, has stepped in at St Basil's Home for the Aged in Fawkner and has set up an emergency response centre with the Victorian government for the wider aged care crisis.

The federal government has set up a call centre for families to get information on their loved ones after widespread confusion.

Aged and Community Services Association chief executive Patricia Sparrow said new guidelines are being rolled out to prevent staff from working across multiple homes, in a bid to reduce the spread.

"It is anything up to about 30 per cent of the workforce that work in multiple facilities," she told Seven.

"It is taking a little while, but the intent is to completely reduce that spread based on principles introduced last week."

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A United Workers Union survey of 1000 aged care staff released on Monday found workers often had not received additional coronavirus safety training or that their aged care facility did not communicate their infection plan well.

It also found workers have been struggling with staff shortages and increased workloads since the outbreak, with structural issues rife.

90 per cent of workers worried their colleagues may have to work if they have mild symptoms because of a lack of sick leave.

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