It could be many months yet before Australia can afford to take its foot off the brake and lift the heavy social restrictions in place to slow the spread of coronavirus, one of the nation's top medical officers warns.
Health experts and leaders are cautiously optimistic about the slowing growth rate in virus cases but even tougher restrictions have been put in place, banning gatherings of more than two people - apart from families - in public and private.
And older Australians have been urged to stay at home for their own protection.
The tougher restrictions come as Tasmania and the ACT recorded their first deaths from the virus, bringing the nation's toll to 18 people.
Deputy Chief Medical Officer Paul Kelly says the flattening of the curve of infections is vital to make sure there are enough hospital and intensive care beds available over the coming weeks.
"This is not a time to take the foot off the brake," he said on Monday.
"We really need to redouble our efforts to work as a society to make sure we are doing everything we can to slow the spread of the virus."
Nearly 4100 Australians have been diagnosed with the virus and 55 are in intensive care, he said.
Playgrounds, skate parks and outdoor gyms across the country have been added to the growing list of closures.
The national cabinet will meet again on Monday evening to consider further measures, including what to do about retail stores - apart from those selling vital supplies such as food and medicines - and other businesses still open, including hairdressers.
The new two-person limit will apply to all indoor and outdoor settings, including private properties, with an exemption for families split across two households.
Residents have been urged to stay at home unless they are working, studying, attending medical appointments or collecting essential supplies.
People over 70 and those who live with a chronic illness are being urged to stay at home and self-isolate for their own protection.
Professor Kelly urged everyone with elderly relatives or who lived near older Australians to think about how to help them, including by fetching groceries or filling prescriptions.
States and territories will decide how best to enforce the new rules, with Victoria and NSW sending in the police.
Victorian Premier Daniel Andrews flagged $1600 spot fines for people caught breaching the restrictions in his state.
"We're not doing this for any other reason than this is life and death," he said in Melbourne.
"If we allow our health system to be overrun, then people will die. That is a price that is not worth paying."
Australian Medical Association president Tony Bartone said it was clear the virus was spreading faster in some parts of the country than others, naming Sydney and Melbourne as hotspots.
"If we see continuing community transmission, that's going to be the first sign that we're going to have to need to move to that (complete lockdown) stage," he told ABC television.
Federal Health Minister Greg Hunt says there have been early signs of the curve flattening, with the infection rate dropping from 25 per cent to the low teens.
"These results are telling us what we are doing is working," he told the ABC.
Prof Kelly said health officials were working on the "exit strategy" for lifting restrictions but warned it was still months away.
"Obviously we want to see the curve not only flattening but starting to bend downwards, and then making that decision about when to take the foot off the brake will be very difficult," he said.
There will be a six-month moratorium on evictions for commercial and residential tenancies in financial distress because of the COVID-19 fallout.
The wages of Australian workers will be also subsidised by the federal government to keep people employed during the pandemic.
Treasurer Josh Frydenberg will detail the wage subsidy scheme on Monday afternoon.
Employers will be legally obliged to keep employees on staff if they take part in the program.
Australian Associated Press