COVID cases in NSW have spiked to their highest level since lockdown lifted, with health authorities bracing for a further surge in cases fuelled by festive season celebrations.

Some 516 infections were detected from more than 90,000 tests on Thursday, but no new virus related deaths were reported.

It is the highest daily tally in NSW since October 9, two days before lockdown lifted.

NSW Health said on Friday it was concerned about the increased transmission in larger social venues such as pubs, clubs, and party settings. They include recent outbreaks associated with the Golden Sheaf Hotel at Double Bay, the Oxford Tavern at Petersham and the Albion Hotel at Parramatta.

“The transmission in these types of settings is contributing to the increase in cases in NSW and we urge people not to attend social functions if they have any symptoms, even if mild,” Dr Jeremy McAnulty said.

Pub alerts issued on Friday

Among the latest cases is a traveller whose diagnosis sparked a short-lived lockdown of a Bondi hostel.

On Thursday afternoon, police cordoned off the Noah’s Bondi Backpackers as NSW Health locked it down and began testing all residents. A spokesperson for the Sydney Local Health District on Thursday night confirmed one case had been detected.

NSW authorities were already battling to contain at least two large transmission events.

A trivia night at the Oxford Tavern in Petersham has sparked a virus cluster, with at least 44 patrons testing positive to COVID after the November 30 event.

Authorities are also concerned about 140 passengers who embarked on a Sydney Harbour cruise on Friday night. It has so far resulted in five cases of the Omicron variant.

The number of people diagnosed with the Omicron variant of COVID-19 in NSW has now topped 40. There were no new Omicron infections on Friday.

Woody’s Surf Shack Night Club in Byron Bay has also been linked to at least three cases, while an event at the Coorabell Hall on Saturday night has resulted in 16 cases.

“As Christmas approaches, and more of us gather with families, friends and colleagues to celebrate, it is particularly important to be vigilant,” deputy chief health officer Marianne Gale said.

Gatherings should be held outdoors wherever possible, she said.

But Premier Dominic Perrottet has urged “confidence, hope and optimism” ahead of the end of most restrictions next week.

From December 15, density limits will be scrapped across NSW, QR check-ins will be required only at high-risk venues, and masks will have to be worn only on public transport, at airports and on planes.

One of the six cases is a student at Broadbeach State School, which was closed on Friday.

‘Virus spread’ on Gold Coast

Queensland has detected six local virus cases and is investigating a seventh just three days before its border restrictions ease.

Health Minister Yvette D’Ath said all six confirmed cases, and the seventh, were on the Gold Coast – with evidence of community transmission across the region.

“Today is the day that we’ve been planning for,” she said on Friday morning.

“I can report that we have new community cases here on the Gold Coast and a number of incursions.”

One case is a partially vaccinated man in his 20s who recently moved to Queensland and has been infectious for five days. One of his close contacts is also positive.

Another is a Gold Coast woman who works at Mullumbimby in NSW, with her partner and their child – who goes to Broadbeach State School – also testing positive.

The woman is fully vaccinated and initially tested negative, before a second positive test.

She has been infectious in the community for eight days, while her partner was infectious at a vaccination centre when he received his second jab.

Their second child, who attends Miami State High School, has tested negative.

A Gold Coast disability worker who travelled to Byron Bay to play in a band has also tested positive, as have three other band members who have since travelled to Western Australia.

Ms D’Ath urged Gold Coast locals to wear masks, check-in to venues and get vaccinated. However, the rise was unlikely to trigger stronger restrictions.

“We don’t know the level of transmission that is happening here right now,” she said.

“It is inevitable that these cases are going to move into Queensland when our borders open on Monday.”

Only 78.1 per cent of more than 507,000 eligible Gold Coast residents are fully vaccinated so far.

Queensland also had two interstate-acquired cases in home quarantine and one case in hotel quarantine on Friday.

More Omicron in Victoria

Victoria has confirmed another two cases of the Omicron coronavirus variant, while others in the community have been cleared.

The health department confirmed the latest cases on Friday, taking the state’s total to three after an Omicron-infected returned traveller was identified in hotel quarantine earlier this week.

Both are travellers from overseas, who touched down aboard a flight from Dubai to Melbourne on November 30.

Genomic sequencing is underway to determine whether a third COVID-positive person on the flight is carrying the variant.

All other passengers have been contacted and asked to get a PCR test, as contact tracers attempt to prevent the variant leaking into the community.

In addition, three previously suspected Omicron cases – none of whom had a history of interstate or overseas travel – have either been confirmed or are likely to be infected with the Delta variant, the health department said.

Premier Daniel Andrews has reiterated the state is not chasing an “Omicron zero strategy”, describing it as unachievable.

The Omicron response update comes after Victoria earlier reported 1206 COVID-19 infections, with all except three locally acquired.

-with AAP