South Australian authorities will not rule out reintroducing restrictions ahead of an expected rise in COVID cases in the coming weeks, as the new subvariants BA.4 and BA.5 take hold.
New modelling released yesterday showed case numbers were expected to peak in three weeks' time with an estimated 5,000 to 6,000 new cases each day — about 1,000 more than previous estimates — as the BA.4 and BA.5 subvariants take hold.
Chief Public Health Officer Nicola Spurrier said the modelling was the "least certain we've been because we don't have a lot to go on" with the new subvariants circulating around the world at the same time.
Professor Spurrier said while the exact size and timing of the peak was uncertain, said she believed case numbers would rise over the next week.
SA recorded 4,072 new COVID cases today, a jump of 932 compared with yesterday.
The state now has 267 people in hospital, up from 234 yesterday, and five people aged in their 80s and 90s have died.
SA Police Commissioner Grant Stevens said if hospitalisation rates hit around 300, authorities would have a "conversation about where we go from here".
South Australia's health system has been under immense pressure for some time and Professor Spurrier said authorities would be watching hospitalisations closely.
"What of course we have to keep our eye on is the impact on our hospitals because as soon as our hospitals get overwhelmed it means that other people that need to go to hospital and have elective surgery and other things aren't able to do so," she told ABC Radio Adelaide.
"But the other thing is, if we have a lot of people sick in our community, then other parts of our society don't function very well.
"You can imagine if you're a business and you've got your whole workforce all of a sudden goes out … then of course you reduce your productivity."
Call for more South Australians to wear masks
Professor Spurrier and Commissioner Stevens urged South Australians to wear masks while indoors, including at workplaces, and around vulnerable people.
Commissioner Stevens said a mask mandate was "up for consideration" but there was "no decision about that at the moment" and it should be a "last resort".
Commissioner Stevens, who no longer has powers to impose mandates, but still sits on the COVID Emergency Management Council, said he was hopeful South Australians would decide to wear masks, rather than needing a mandate.
"If people do the right thing and we just start taking small steps like wearing masks in densely-populated areas and when we're visiting people who are vulnerable, that could be enough that we don't need to take the next step," he said.
Professor Spurrier said South Australians tended to "hear a message, understand the importance of it, and then just get on and do what they need to do" without requiring a mandate.
Implementing a mask mandate would require a declaration of either a state of emergency or a public health emergency.
"I think people will have appreciated that the pandemic has now got to another phase where we are going to have infection in our community, and it's going to continue there for many years to come and we can't stay in a state of emergency," she said.
Cases of BA.4, BA.5 variant rising
Genome sequencing has shown the number of BA.4 and BA.5 cases have been rising in SA.
Professor Spurrier said SA Health sampling showed the two variants made up about 12 per cent of cases.
She said the new variants were "definitely taking over which means it has a biological advantage".
"It has immune escape, so if you've had an infection before and it would have been with BA.1 or BA.2 then you're susceptible to being infected with BA.4, BA.5," she said.
Commissioner Stevens said the new subvariants were "far more transmissible" and although early indications showed it was no more severe than previous variants, rising case numbers could impact the health system.
"The risk for that is, if it's far more transmissible, more people will be sick at the same time and if even a small proportion of those people require assistance of health services that could continue to put the health system under stress," he said.
