New South Wales has recorded 804 new Covid-19 cases, the highest daily total since October 2 when 813 cases were recorded.
The state's daily cases dipped as low as 135 at the start of November but have climbed steadily in recent weeks.
Authorities also announced one new death from the virus today. There are now 168 people in hospital with 21 in intensive care.
The reproduction rate of the virus in NSW is currently at its highest in four months, according to University of Australia biostatistics professor Adrian Esterman, at 1.43 – meaning for every 100 new cases, another 143 people contract the virus.
More than 1.9 million coronavirus case alerts have been issued in the Service NSW app over the past fortnight – including directions to monitor for symptoms, as well as to test and isolate as contacts of a case – as celebrations drive community transmission.
A cluster in the city of Newcastle is expected to grow after a Covid case, expected to be infected with the Omicron variant, visited Finnegan's Hotel on December 10. People at the venue at the same time must immediately get tested and isolate for seven days.
Rugby league players and staff for the Newcastle Knights are also isolating after being linked to a superspreader Omicron outbreak at The Argyle House nightclub. No players have yet returned a positive result.
All 680 people who attended the nightclub are considered close contacts and are required to isolate for a week. Of the attendees, 84 have so far tested positive for the virus.
Under current rules, fully vaccinated people who are considered close contacts of a Covid-19 case must isolate for seven days, testing on days one and six; casual contacts can exit isolation after they get a negative test result.
Australian National University infectious diseases physician Peter Collignon said that with boosters being rolled out and no indication of rocketing hospitalisations and deaths, classifying large groups of nightclub revellers as close contacts was overkill.
"[Omicron] spreads more than Delta, but the consequences aren't more than Delta," Collignon told The Daily Telegraph. "We should treat it the same as Delta. We have to be careful not to overreact."
NSW chief health officer Kerry Chant has urged residents to avoid functions if they have any symptoms, no matter how mild.
"If you have the opportunity to be selecting venues, choose outdoors venues or well-ventilated spaces, airy spaces as they're more Covid-safe," Chant told reporters on Sunday. "Also, we are asking that you consider doing a rapid antigen test before going out, even if you don't have symptoms."
The Argyle House nightclub outbreak is linked to a party boat cruise on Sydney Harbour on December 4 where at least three people tested positive for the Omicron strain.
Health authorities believes some of the guests at that party then travelled to Newcastle and attended the nightclub.
NSW is set to go ahead with plans to further ease the state's Covid-19 restrictions from tomorrow.
The change will see unvaccinated residents included in the state's new freedoms, along with an end to mask-wearing in the majority of indoor settings, QR code check-ins only required at limited venues and an end to density limits.
Of the population aged over 16 in NSW, 94.8 per cent have had their first jab, while 93.1 per cent are fully vaccinated.