There are 813 COVID-19 cases currently in hospital, including 126 in intensive care, of whom 54 are being ventilated.
NSW Health's Jeremy McAnulty said of those 126 in intensive care, 113 were not vaccinated and 12 had received one dose of vaccine.
Dr McAnulty said two ICU patients had been fully vaccinated but acute symptoms were uncommon in fully vaccinated people.
"The vaccine is great, we know it is around 90 per cent if you are fully vaccinated, of protecting from severe disease, hospitalisation and death.
"But it is not perfect, it is not 100 per cent, so unfortunately we do get breakthrough infection sometimes, even in people who have had two doses."
The main areas of concern remain around Western Sydney (466 total cases) and the south west (421 cases), with concern around the suburbs of Guildford, Merrylands, Auburn, Greenacre, Bankstown, Punchbowl and Blacktown.
Twenty-five new cases were reported in the Western Sydney Local Health District to 8:00pm yesterday.
Dr McAnulty said COVID-19 fragments had been detected in sewage in regional areas including Trangie, just west of Dubbo, Byron Bay on the north coast, Cooma in the southern Tablelands and Tamworth in the north.
The Premier said she was disappointed to hear of an alleged arson attack on a COVID-19 testing clinic in North St Marys in Western Sydney overnight.
"It is always disappointing when people ignore health advice or pretend that COVID-19 is not serious," she said.
