Australia's coronavirus tally could hit 2000 cases by the end of the day as authorities develop new rules about who can get tested.
NSW and Victoria reported 205 new cases on Tuesday morning, taking the national tally to 1914. Australia's death toll stands at seven, all but one in NSW.
Other states are yet to add their new cases. They include Queensland which recorded 60 fresh positive results on Monday - it's highest daily increase so far.
The World Health Organisation warned overnight that the coronavirus pandemic is accelerating, with more than 300,000 cases now confirmed and thousand upon thousands of deaths.
It took 67 days from the first reported of the virus to hit 100,000 cases, 11 days for the second 100,000, and just four days for the third 100,000.
WHO says it's still possible to change the trajectory of the pandemic, urging countries to adopt rigorous testing and contact-tracing strategies.
Australia's Deputy Chief Medical Officer Paul Kelly says testing criteria for coronavirus will change as a result of sweeping travel bans that have lessened the risk of imported disease.
Current rules require tests for people who fell ill within two weeks of returning from overseas, or had contact with such a person.
But Prof Kelly has indicated a rule change that's more focused on community transmission, telling the ABC the traveller component would be removed.
"There will be announcements about that over the coming days," he told the ABC's Q&A program on Monday night.
On Tuesday morning, NSW reported 149 new cases, taking its tally to 818. Victoria added another 56 people to its list of infections, taking the state tally to 411.
Queensland has recorded 319 cases since the outbreak began, but won't reveal how many new cases it's had in the past 24 hours until later on Tuesday.
In Western Australia, police and Australian Border Force officers will ensure passengers do not leave a cruise ship that has docked at Fremantle Port.
Premier Mark McGowan says no one will be allowed ashore while the vessel refuels before heading for Dubai, amid fears at least 250 peope are suffering an upper respiratory illness.
The operator of the ship, which left Italy in January, has denied reports of widespread illness, but Mr McGowan isn't taking any chances after dozens of people with coronavirus disembarked from a cruise ship in Sydney.
Political and health authorities are ramping up the message for people to stay home and implement social distancing, as states including WA and Queensland announce more cash to help workers and businesses survive.
NSW Premier Gladys Berejiklian says the state is now at a critical stage, and people needed to self-isolate where necessary, stay home if they can, and social distance.
"This is a difficult time for us, but I am confident NSW will control as much as we can the spread of this virus, so long as everyone steps up and does what they need to do," she told reporters on Tuesday.
She warned that people would face harsh penalties if they were told to self-isolate but didn't.
NSW Police Minister David Elliott has called the decision to let passengers leave the Ruby Princess cruise ship in Sydney was a "monumental stuff up". At least 50 people from that vessel have the virus.
Victorian Premier Daniel Andrews made another appeal for people to grasp the gravity of the situation.
"Turn your TV on - have a look at Italy, have a look at Spain, have a look at France," Mr Andrews told Triple M Melbourne on Tuesday.
Some states have closed their borders while others are tussling over school closures amid fears the pandemic could affect Australia for months to come.
Border controls are now in place for South Australia, Western Australia and Tasmania, with only freight and essential travel exempted. Queensland will close its borders on Wednesday.
Schools remain open in South Australia, Tasmania, Western Australia and Queensland.
NSW is also keeping schools open but Ms Berejiklian has told parents to keep their children home if possible.
Victoria and the ACT have moved to early holidays to give schools time to set up online and distance education arrangements, while private schools are making up their minds.
Prime Minister Scott Morrison warned Australians face six months of severe but necessary restrictions, with pubs, bars, nightclubs, cinemas and other indoor venues forced to close.
Supermarkets, petrol stations and pharmacies remain open.
He also warned of a dire year ahead for many, including thousands of Australians who have or are expected to lose their jobs.
Huge queues began forming early on Tuesday outside Centrelink offices as many people who lost their jobs on Monday apply for welfare payments.
The MyGov online portal also crashed on Monday after it was overwhelmed by jobless Australians.
Social Services Minister Anne Ruston says no one could have predicted the spike in demand, even though the government shut down entire sectors of the economy.
The government has since asked people trying to register with Centrelink to wait a few days.
"We are asking for patience and calm ... What we saw yesterday was heartbreaking," Senator Ruston said.
© AAP 2020