NSW recorded 233 cases of community transmission to 8pm on Tuesday night, with NSW Premier Gladys Berejiklian saying at least 47 of these were infectious in the community for that time.

"Very sadly, a male in his 20s passed away from COVID from south western Sydney overnight," she said, offering her condolences to his family at Wednesday's media conference.

"It demonstrates again how this disease is lethal, how it affects people of all ages."

The Premier said the man, who died at home on Tuesday evening, was not vaccinated.

"As we understand it, the death happened quite suddenly," she said.

"People who are vaccinated are staying out of hospital, are staying out of ICU."

The woman in her 80s was from the inner west at the Royal Prince Alfred Hospital. She tested positive on July 27 and was at the hospital since then. She was not vaccinated.

There are currently 286 COVID-19 cases admitted to hospital, with 53 people in intensive care, 23 of whom require ventilation.

Newcastle and NSW Hunter Valley residents have been urged to come forward for testing after "very high viral load" was detected in the region's sewage.

"There were very high rates of virus detected in the sewerage in the Hunter area," Ms Berejiklian said.

"The very high viral load suggests there could be undetected cases up around the Hunter area."

Chief health officer Dr Kerry Chant said health authorities were "very concerned".

The detection was from both the Shortland and Burwood plants, as well as a "lower detection" at Belmont.

Birmingham Gardens, Shortland, Maryland, Fletcher, Minmi, Cameron Park, Stockton and Fern Bay were among the suburbs flagged as priorities for testing.

Dr Chant said everyone with symptoms to go home immediately after a test, and said testing could help authorities determine what was behind the result.

More than 105,000 people were tested in the 24-hour period.

The NSW coronavirus cluster led the Victorian government to change the border bubble rules from midnight Tuesday.

Border businesses once again scrambled to make arrangements ahead of new travel restrictions coming into place.

Wednesday's figures revealed Victoria's return to "doughnut days" with no new local coronavirus cases reported and none acquired overseas.

Queensland has recorded 17 new locally-acquired COVID-19 cases, taking the west Brisbane Delta cluster to 63 cases with another unlinked case emerging in the state's far north.

MORE COVID NEWS:

EARLIER: The quick spreading Delta has seen Prime Minister Scott Morrison changing tune from lauding NSW's insistence on staying open and managing COVID-19 with testing and tracing to saying hard and fast lockdowns were the order of the day.

"It is indeed true that for a very long period of time in NSW, they were able to manage cases as they arose by not having to go into lengthy and extraordinary lockdowns," Mr Morrison said in Question Time.

"But the virus writes the rules."

IN OTHER NEWS:

With Greater Sydney and surrounds approaching six weeks of lockdown and daily infections remaining stubbornly high, the NSW government is now looking to vaccination as a way out of the outbreak.

And the debate around incentives to get vaccinated continues on.

Morrison and state and territory leaders have set a vaccination rate target of 80 per cent before harsh restrictions will be a thing of the past.

But scientists and political leaders are at odds as to how this can be achieved.

- additional reporting KIM CHAPPELL

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