Australia is expected to follow other parts of the world in expanding eligibility for a fourth COVID vaccine dose to the wider population.

As the nation grapples with rising case numbers, Prime Minister Anthony Albanese says immunisation experts will look at available evidence before making a recommendation.

"The pandemic isn't over, so my view is that (Australia) will inevitably follow what has occurred in other parts of the world and roll out a further booster shot," he told reporters in Sydney on Wednesday.

"I'd encourage people who haven't had their booster shots to go out there if they're eligible and do it as a matter of urgency."

The Australian Technical Advisory Group on Immunisation is expected to discuss the benefits of expanding the fourth dose eligibility at its meeting on Wednesday.

A fourth dose is currently available for Australians aged 65 and older and vulnerable people.

Meanwhile, Victoria has extended its pandemic declaration by three months until at least October 12.

In a statement on Tuesday, Premier Daniel Andrews said he was satisfied COVID-19 continues to pose a "serious risk" to public health throughout the state.

This, he said, justified ongoing public health measures over winter to reduce the risk of transmission and hospitalisation.

NSW Health Minister Brad Hazzard also warned that anyone who isn't fully vaccinated is "crazy" as the state braces for a third wave to peak in late July and early August.

The surge in cases is being driven by two Omicron sub-variants, BA.4 and BA.5, and health experts believe the number of cases and deaths will continue to grow.

State and territory health experts are also considering whether to reintroduce mask mandates to curb the case increase.

As Victoria's death toll rose above 4000, Premier Daniel Andrews said he couldn't make it any clearer that vaccines worked.

However, he stopped short of telling Victorians to don masks outside of the current mandated settings such as health and aged-care facilities, and public transport.

On Tuesday, there were 3740 people with COVID in hospitals across the country, the highest levels since the height of the Omicron wave in February.

More than 36,000 infections were reported nationally and experts warn case numbers will climb further during winter.

LATEST 24-HOUR COVID-19 DATA:

Victoria: 10,056 cases, 23 deaths, 523 in hospital with 29 in ICU

NSW: 13,775 cases, 10 deaths, 1822 in hospital with 64 in ICU

Tasmania: 1700 cases, one death, 79 in hospital with two in ICU

Queensland: 5878 cases, four deaths, 705 in hospital with 18 in ICU

ACT: 1477 cases, no deaths, 135 in hospital with five in ICU

WA: 6296 cases, one death, 226 in hospital with eight in ICU

SA: 4072 cases, five deaths, 267 in hospital with 11 in ICU

NT: 342 cases, no deaths, 24 in hospital with one in ICU