'We're all vulnerable again': Grim Covid warning for Australians

Australians have been issued a grim warning as the country continues to battle new Covid Omicron sub-variants BA4 and BA5 and rising reinfections.

ABC Health Report host Dr Norman Swan warned "we're all at risk" as Covid-19 continues to perplex immunologists around the world.

On Monday, more than 39,000 new cases were confirmed in Australia. Meanwhile, over 341,000 active cases were recorded across the country as reinfections continue.

Speaking on ABC News, Swan revealed even those that are fully vaccinated and have previously been infected are still at risk of becoming reinfected because the BA4 and BA5 subvariants are "more vaccine and immune evasive".

"So if you've had a previous infection or had vaccines, you're more likely to catch it," he said on Monday. "We're all vulnerable again."

Long-term complications not prevented by vaccine

While the vaccines are "still pretty effective against severe infection and death," Swan warned they're "not protecting us against infection in the first place."

Until now, immunologists expected we'd become more resistant to the virus as time went on but new variants every six months is what's leaving experts stumped.

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"It turns out when a new one comes along, we are vulnerable again," he warned, adding it's not seasonal and has "nothing to do with winter."

"It's much more to do with the virus and immunologists are getting more and more perplexed about how it is operating," he said

With more people getting Covid-19 a second time, Swan revealed we're more at risk of getting longer-term complications like myocarditis, an inflammation of the heart.

Each time someone is infected with the virus, "the risks accumulate" and it can't be prevented by the vaccine.

'We are seeing a silent pandemic'

Despite life returning to normal for most of us, the pandemic is "still ongoing," said Epidemiologist and Professor Archie Clements from Curtin University’s School of Population Health.

"But now we are seeing a silent pandemic, with rising numbers of deaths in the community that are not receiving the level of national prominence that we saw over the previous two years," he said.

Prof Clements said "we're not out of the woods yet," as Prime Minister Anthony Albanese said Australia's latest Covid surge will peak in August.

"It is expected from the indications of (Chief Medical Officer) Professor (Paul) Kelly that we can expect an increase in the number of cases over the coming weeks," he told reporters on Saturday after meeting with state and territory leaders at National Cabinet.

Isolation requirements won't change, says PM

He also revealed the isolation period for positive cases would not change from seven days to five, despite comments from NSW Premier Dominic Perrottet, who said it was time for a review of the requirements for workers.

Given the increased spread of the virus, a review of isolation rules was not underway, Mr Albanese said.

"The advice from the chief medical officer ... was that now is certainly not the time for (the isolation period) to be reconsidered," he told Adelaide radio 5AA on Monday.

Mr Albanese called on people to wear masks when social distancing was not possible and to take precautions.

With AAP

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