NSW has recorded its worst day yet since the pandemic began with 633 new COVID cases and three more deaths.
A man in his 60s who was a patient in the Liverpool Hospital geriatric ward has died as well as two men in their 70s who both died at Nepean Hospital.
Of the new cases, 550 were from south-western and western Sydney with the vast majority younger people.
Sixty-two were infectious in the community, 30 were partly isolating and the status of 447 cases is under investigation.
The count of COVID-19 patients in hospital has grown to 462, including 77 in intensive care and 25 on ventilators.
Premier Gladys Berejiklian announced the disturbing escalation in the case numbers on Wednesday, warning the state had "not seen the worst" of the outbreak.
"Just stay home," she said.
She said most transmission was occurring in workplaces and households.
The government remains concerned about indigenous communities in western NSW and urged anyone who had been in Wilcannia to come forward for testing.
She also said West Dubbo continued to be an area of concern.
"I can't express enough my level of concern," chief health officer Kerry Chant said of the 633 new cases.
"Whilst vaccination will be an aid and essential... our vaccination coverage at the moment is far too low. We need to do everything we can to not come in contact with anyone."
"We have a collective responsibility to stop seeing those deaths and hospitalisations increase.
"Please be cautious wherever you are in the state."
Dr Chant said there had been 23 new cases of COVID in western NSW, with 17 in Dubbo and one at Bourke, bringing total case numbers to 139.
There are 462 people in hospital, with 77 in intensive care.