South Australia has reported another record of 688 new COVID-19 infections amid fears for the state's health system if action is not taken to slow the spread of the new Omicron variant.
Premier Steven Marshall says officials have been monitoring the rise in cases carefully right across the country.
"What we are very concerned about is the very significant increase in transmissibility. We do have to take action," he said on Friday.
"We've updated our forecasts here in South Australia and if we don't take action there is going to be a significant problem for our country.
"The sheer volume of cases could overwhelm health systems right around the world."
Gene sequencing on the SA outbreak has revealed 70 per cent of the new cases are now the Omicron variant.
In response, SA has removed a ban on the widespread use of rapid antigen tests, but only as a screening tool for people without symptoms.
It has also welcomed the decision to cut the interval between a second dose and a booster shot to four months.
For at least the next four weeks people are encouraged to work from home.
A range of local restrictions that were due to be eased on December 28 will stay in place into the new year with a date to be determined.
Mr Marshall said there was no way they could be relaxed in the current circumstances.
In relation to the rapid antigen tests, the government has recommended they be used before entering high-risk settings such as nursing homes, before going out where there may be crowds, before going to work, or as reassurance for asymptomatic people feeling anxious or worried in the current COVID climate.
It is also hoped that will reduce demand on the state's virus testing centres which have been swamped in recent days.
Anyone who tests positive on a rapid antigen test must get a more conclusive PCR test and isolate until they return a negative result.
Chief Public Health Officer Nicola Spurrier said eight people were currently in hospital with one man in his 30s on a ventilator in intensive care.
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Australian Associated Press
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