New South Wales has recorded 2,566 new COVID-19 cases, another daily record for the state, and no new deaths as health authorities advise residents to wear masks and stay outside as the mercury rises.
There are currently 227 people being treated for COVID-19 in NSW hospitals, 28 in ICU - up from 206 people in hospital and 26 in ICU on Saturday.
Victoria reported 1,240 new cases on Sunday, down slightly from the 1,504 cases reported on Saturday, and four more virus-related deaths.
There are 392 virus patients in hospitals across the state, 81 of them in intensive care and 41 requiring ventilation.
There were 384 patients in hospitals on Saturday, 84 in ICUs and 43 on ventilators. The seven-day hospitalisation average has risen marginally to 380.
The spike in cases in NSW comes as a handful of positive cases at a Byron Bay caravan park in NSW meant dozens of guests - including schoolies - have had to isolate inside their caravans and cabins.
NSW Health urged people to socialise outside where possible to help stop the spread.
"It’s getting hot hot hot. Don’t stay indoors if you are comfortable outside. You’re less likely to catch COVID-19 outdoors or in well-ventilated spaces. If you have to use the air conditioner, put it in a non-recirculating setting," it tweeted.
In Victoria, an outbreak at Camp Rumbug in South Gippsland that began last week has grown to about 50 cases across two Melbourne schools, with hundreds of people forced into isolation.
As of Saturday authorities were still to discover further Omicron cases among infected patrons at two Melbourne nightclubs, keeping the state's total for the variant at 19.
Genomic sequencing has so far confirmed one of 30 infected people linked to the two night spots has the Omicron variant.
Health authorities are also still working to determine if any of 16 cases tied to Collingwood's Peel Hotel and 14 to Fitzroy's Sircuit Bar, have it.
The outbreaks, coming a week before Christmas, have thrown travel plans into disarray.
Case numbers are also rising in other parts of the country, with South Australia reporting 80 new cases on Sunday, Queensland reporting 42, ACT posting 18, the Northern Territory recording nine and Tasmania, three.
Tasmanian Premier Peter Gutwein announced on Sunday that masks will be mandated indoors in the island state.
Masks will be mandatory across all indoor settings, public transport and ride shares from 12.01am on Tuesday.
"We've done this before. It's important. In fact, a lot of Tasmanians are already doing it," Mr Gutwein said.
Australians urged to get boosters, wear masks
Health Minister Greg Hunt on Sunday urged Australians to "please don't wait, please come forward" if they are due for a first or second dose or a vaccine or a booster shot, available five months after a second jab.
Australia’s first dose rate stands at 93.8 per cent while 90.4 per cent of Australians are fully vaccinated, he said.
Around 1.3 million people have received their booster shots, with more than 640,000 doled out in the last week.
Mr Hunt said the government had prepared "extremely large volumes of vaccines to cover the Christmas period".
"Over five million vaccines are in place, with another two million-plus being expected to be delivered in the lead-up to Christmas and then in the days beyond."
He said he had also requested states and territories to keep state clinics open over the period.
Deputy Chief Medical Officer Sonya Bennett on Sunday pleaded with Australians to continue to wear masks, even in the absence of a mask mandate.
"First and foremost, I'd probably encourage everyone to think about continuing to wear masks, particularly in settings that are indoor, public indoor spaces that may not be well-ventilated. Think about wearing a mask. It's a simple, easy thing to do," she told the media.
"My plea to the community is we don’t need to wait for mandates to tell us what is sensible to do. That particularly applies to masks. They’re simple, we’re used to it ... I ask the community to consider that they use that. That they make their own choice to use a mask when necessary."
She also asked people to mix outdoors where possible.
"If you're having gatherings, think about having them outdoors or in well ventilated spaces. Limit numbers. And try and be safe and socially distance."
Dr Bennett said there was still "a lot of uncertainty around Omicron".
"It is highly transmissible and appears to rapidly escalate with what’s called the doubling time of around two days. Which is obviously concerning."
In NSW, Premier Dominic Perrottet said rising COVID-19 case numbers were "the new normal" and he urged residents to come forward for boosters.
Deputy Chief Health Officer Dr Sonya Bennett has urged Australians to continue to wear masks even in the absence of a mask mandate. Source: AAP
"We said vaccination is key to ensuring we're able to open up as quickly as possible, as safely as possible. And to see so many people go out and receive that booster shot, particularly as we go into Christmas, has been incredibly pleasing," he said.
"It's the efforts that everyone is making across our state that ensures we remain safe and our families remain safe, particularly over the Christmas period."
Health Minister Brad Hazzard said 40 per cent of vaccinated NSW residents would be eligible for a booster shot by the end of April.
He also urged people to continue to wear masks as the state adapted to rising case numbers once more.
"If you're in close promise proximity to people inside and it's a big group of people, consider wearing a mask. We also have to live our lives in a more normal way coming into 2022. We'll continue to strike the balance. We'll continue to look at all the issues that are happening around the world, but also here in our state, and we'll make sure that people's mental health and the economy is also well looked after."
Mr Perrottet added that NSW "strongly encourages" masks but won't mandate them, given "there's always different views".
He did however suggest restrictions could be reintroduced over coming months.
"When we believe there's evidence in front of us that we need to potentially tighten restrictions we will," he said. "And it's almost certain as we move through, as we see overseas, as they head into the winter months, certain challenges will come our way," he said.
"There will be curve balls, certain things we don’t expect. There’s almost certainly to be other variants that may come our way, and we’ll need to respond."
Lockdowns in Australia 'not likely'
When asked if Australia could face another lockdown, given the Netherlands is going into lockdown again due to skyrocketing Omicron cases, Mr Hunt said the two countries remained in very different circumstances.
"They’re going into the depths of winter with a vastly higher case rate and sadly having had a vastly higher loss of life. So a different country, different circumstances.
"We're going into summer, we have one of the highest vaccination rates in the world, and a very different set of circumstances. But each country will make their judgement on their own circumstances ...So we don't see that's a likely situation in Australia. We are well prepared and people are overwhelmingly, I have to say, continuing to do an amazing job."
Mr Hunt said no states or territories had indicated further restrictions at this point in time and Australia remained "overwhelmingly towards opening up".
"The clear direction is higher vaccination and less restrictions, but acknowledging that, you know, in individual cases there may be specific measures that may be required."
With AAP
