Morrison plays down fresh Covid restrictions as experts say boosters best way to tackle subvariant

States should not rush to reintroduce Covid-19 restrictions in response to a predicted surge in cases in coming weeks, health experts say, insisting that raising booster coverage of older Australians will be far more effective against the new BA.2 subvariant than masks and curbs on movement.

The advice against tougher Covid rules comes after the Sydney Morning Herald reported NSW Health had recommended a return to an indoor mask mandate, working from home and density limits, as well as bans on singing and dancing, as cases in the state are expected to double.

But the New South Wales health minister, Brad Hazzard, said he was “not at all keen” to adopt the recommendations.

“Bringing restrictions back in is the last possible course we want to go,” Hazzard told the Sydney Morning Herald.

It was not clear whether the advice recommended reintroducing the rules – which would resemble Covid settings in place in early February – immediately, or once cases began to rise.

On Saturday – a day after national cabinet moved to scrap quarantine requirements for all Covid-19 close contacts – Scott Morrison also played down the idea of states reintroducing virus restrictions.

“What we’ve seen with these latest permutations of this variant is it doesn’t need to change our settings. We can keep doing what we’re doing,” the prime minister said.

“We may see some more cases, but as we’ve known now, and I’ve been trying to be, trying to say for a long time, cases is not the point. How your hospital system is going is the point, and our hospital systems have held up extremely well.”

Morrison declared he wanted to end the requirement for Covid close contacts to quarantine as soon as possible.

“It’s starving businesses of staff ... so that rule is becoming, we believe it is redundant,” Morrison said.

There were 31,721 new Covid cases announced nationally on Saturday, with 12,850 in NSW and 6,075 in Victoria. There were 22 new deaths – 11 in Victoria, six in Queensland, four in NSW, and one in South Australia.

Nationally, 65.3% of the eligible population had received a booster dose. However, a federal health department spokeswoman told Guardian Australia the department did not have data readily available on the booster rate for over-50s.

However, on Friday, the health minister, Greg Hunt, said the coverage rate was in the “high 90s for boosters for the over-70s”.

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Prof Robert Booy, a University of Sydney infectious diseases paediatrician and vaccinology expert, said it was more important to increase the booster rate than reintroduce restrictions.

He said he had recently seen data that showed about 15% of people aged over 65 have not yet received their Covid-19 vaccine booster dose.

“There are still these vulnerable people who aren’t yet boosted who must get boosted now,” he said.

“Rather than trying to shut down society yet again, we should seek this month, even these next two weeks, to get as much of that older unboosted population their third dose, as well as anyone who is eligible for any dose to get it.”

Booy said those who know they are more susceptible to the severe effects of Covid should take it upon themselves to continue to wear masks indoors and in places of poor ventilation. He added that if case loads grew to a rate where they posed a risk of overwhelming the health system if the government didn’t intervene with restrictions, then health authorities could consider reintroducing measures such as banning singing and dancing and some density limits indoors.

However, Booy said current case numbers did not yet require such a decision.

“I think we really need children in school and people in work. We’re not at business as usual just yet, but we’ve been heading there, and we need to move on and take advantage of our high levels of immunity,” Booy said.

Prof Fiona Russell, an infectious diseases epidemiologist at the Murdoch Children’s Research Institute and director of child and adolescent health PhD program at the University of Melbourne, agreed it was not necessary to reintroduce restrictions.

She said initial data on the BA.2 subvariant that is driving an uptick in cases in NSW suggested that while it was not more severe in effect than Omicron, it was more transmissible.

“The key difference is transmissibility, and that means restrictions and non-pharmaceutical interventions will have less of an impact.

“There needs to be a booster blitz now, before looking at new restrictions. The really critical thing now is to get the booster dose coverage higher, especially of the older populations, because they’re who end up in hospital and are more likely to die.”

She noted that deaths in Hong Kong were now “skyrocketing”, despite efforts to eliminate community spread of Covid, with its high death rate largely due to low booster rates among older residents.

Russell said Australia should be aiming for a national booster rate coverage of about 95% for those aged older than 50.

She said those who are more susceptible to severe Covid, unboosted, and the unvaccinated, and those in crowded indoor settings, should be wearing masks now. “I don’t think we need more restrictions, most people know what to do to keep safe,” she said.

“It’s just going to whip through even quicker than Omicron, you likely won’t even know you’ve got it until it’s too late to rely on isolating to prevent spread. What worked for previous variants just doesn’t work, however we are reassured that the vaccines work well for the subvariant,” Russell said.

As well as moving to end quarantine requirements for all close contacts of Covid cases as soon as possible, national cabinet wants to transition away from PCR testing.

Healthy people with mild respiratory illnesses will instead be encouraged to undertake voluntary self-isolation while symptomatic.

The Australian Health Protection Principal Committee will urgently review both measures and report back to the nation’s leaders.