Coronavirus cases in Victoria have hit a record high with 484 new cases reported in the last 24 hours, taking the total number of cases in the state to 6739.
Another two men in their 90s have also died from Covid-19. Both had been living in aged care. They bring the state's deaths from the Covid-19 coronavirus to 44.
Premier Daniel Andrews said the new case numbers had not been coming down "as we would like them to".
He said nearly nine in 10 people did not isolate between the time they first felt sick and when they went to get a test, based on a study of 3810 cases between 7 July and 21 July.
"We just can't have that any longer," he said.
He warned the number of new cases could continue to rise.
"Unless people who get tested are staying at home and isolating until they get their test results, then we will not see those numbers come down," he said.
"They will continue to go up and up. And a six-week shutdown will not be for six weeks. It will run for much longer than that."
Chief Health Officer Brett Sutton said a move to much tougher restrictions, like those used in New Zealand, was not necessarily the answer to Victoria's problems.
"We have to be targeted in terms of seeing where the issues are and addressing them directly," he said.
Andrews said health officials were working to increase the number of people who were waiting at home for the result of a coronavirus test.
"We certainly cannot have 1 in 2 people who are waiting for a test result simply going about their business as if they didn't have symptoms," Andrews said.
Andrews said a hardship payment of $1500 was available so that people did not have to make a choice between going to work and staying home when they were sick.
He said government officials were looking at whether they needed to boost that payment.
"We will provide you with that support so that you can stay at home and do the safe thing - the right thing," the Premier said.