Epidemiologist Catherine Bennett says while it is hard to gauge daily case numbers with disruptions on weekends and rapid antigen test figures now being added to the data, the number of new infections seems to be settling.

"We are seeing a consistent pattern, even within our RATs that are newly reported, that suggests this is really flattening out," she told Sky News.

"We were seeing doubling of cases every four days not that long ago and we're nowhere near that now. Some days we are seeing less on average than we were four or five days ago."

Professor Bennett said it may take time for infection numbers and hospitalisations to drop but it was a good sign things are starting to settle down.

"We are not there yet but hopefully if we stop seeing cases rising, that's the first step," adding hospitalisations and case numbers would follow.

South Australian Premier Steven Marshall said the state was at or around its peak with less than 4000 cases on Monday.

Mr Marshall said the fact more people were recovering from the virus each day compared to new cases was another indication of waning infections.

Victoria's Chief Health Officer Brett Sutton said while there was a lot of uncertainty, the state is reasonably close to its peak after 22,429 cases and six deaths were recorded on Monday.

Professor Sutton said hospitalisation numbers were also yet to hit their peak, which he predicted may not be reached for a month due to a two-week lag between case numbers and admissions.

Queensland is predicting outbreaks to peak on the Gold Coast in the next week and then Brisbane shortly after.

It follows 15,122 cases and seven deaths in the state on Monday.

While case numbers remain relatively high, Health Minister Greg Hunt said data was pointing to a plateau for new infections.

Mr Hunt said there were clear signs from NSW and the ACT that numbers are steadying, with more than 29,500 and 1600 infections on Monday respectively.

"There are signs of a plateauing, and that is playing itself through in terms of the number with serious illness as well as the number of those who are being diagnosed," he told ABC Radio.

Meanwhile, union leaders called for free rapid tests and workplace safety plans after an emergency meeting on Monday.

Unions are reserving their rights to call for members to cease work or to ban unsafe practices if employers fail to act.

Shadow treasurer Jim Chalmers said the government needed to engage with workers.

"The most important thing we need to see from Scott Morrison is for him to fix this mess that he's made of rapid antigen tests," he said.

The prime minister said changes to the definition of close contact and testing requirements were alleviating pressure on supply-chain issues.

However, he said Australia was not unique in its shortages of rapid tests.

"The rapid antigen tests are in short supply all around the world. (Omicron has) disrupted everything," Mr Morrison told Sydney radio station 2GB.

But the CEO of peak industry body Pathology Technology Australia says the government didn't read the tea leaves particularly well.

"We should have thought that potentially an Omicron style of variant was possible and rapid antigen tests would have played an important role," Dean Whiting told the Ten Network, estimating large volumes of the tests would not arrive until mid-February or March.

Australian Associated Press