The so-called Avalon cluster, linked to an RSL club and bowls club on the peninsular, is now at 28 cases and growing. The easing of social restrictions, and complacency around precautionary measures, has been blamed for cases now popping up in other parts of Australia’s biggest city.

While the strain of virus is thought to have originated overseas, perhaps in a traveller or flight crew member arriving from the United States, is has already been carried to Queensland by a Sydney woman.

Queensland’s Chief Health Officer Jeannette Young today said the woman in her fifties had flown to Brisbane on December 16. Passengers on Virgin flight VA925 have been warned to look out for symptoms and contact tracers will identify those most at risk.

Fortunately, the woman travelled around south-east Queensland on her own in a hire car, limiting the risk of spreading the virus she did not know she had. However, she still visited Eight Mile Plains and went for lunch at The Glen Hotel, before driving to the Sunshine Coast where she is believed to only have had contact with a hotel receptionist.

The following day, the woman was alerted to the risk she may have caught COVID-19 at one of the Avalon venues and went to Prince Charles Hospital for a test. As a precaution, she seemingly opted to drive back to NSW rather than fly, and had already left the state when the diagnosis was made.

“That test result came back positive last night so we started all that contact tracing,” Young said this morning.

NSW is imposing restrictions on the northern beaches and Queensland has declared the council area a hotspot and urged people to avoid travel. From 1am tomorrow, all travellers from that council area will be directed into hotel quarantine as soon as they arrive in Queensland. Police will meet all arriving flights and also conduct surveillance along border roads that remain open at this stage, and it is not clear how long these measures will be in place.

Young said the ability of contact tracers in NSW to connect a growing number of cases would determine whether other council areas were declared hotspots due to community transmission of COVID-19.

However, she warned Queenslanders to reconsider any Sydney travel plans over Christmas, as NSW authorities took the extraordinary step of asking people to rethink festive gatherings.

“If things rapidly escalate through the rest of Sydney other areas might be declared hotspots,” Young said.

Asked about the likelihood of greater Sydney being declared a hotspot – again – before Christmas, Young replied: “I really don’t know.”

Queensland Health Minister Yvette D’Ath acknowledged people were more likely to gather together over Christmas and urged families to consider whether it was worth the risk.

“We want to make sure people are here for future Christmases,” D’Ath said.

Queensland Premier Annastacia Palaszczuk returned early from holidays to brief the media on the latest health advice, describing it as a rapidly developing situation that required her close attention.

“When the NSW premier says she’s on high alert, we are on high alert as well,” Palaszczuk said of her long-time political adversary.

NSW Premier Gladys Berejiklian largely directed her comments to the people of Sydney, warning of the likelihood the cluster would get bigger. She said Sydney-siders would be “crazy” not to wear masks in busy public areas and should consider the impact of loved ones potentially being infected over Christmas.

While acknowledging the northern beaches area was a fair target for travel restrictions, Berejiklian urged other states against rushing to block everyone from NSW. It could be interpreted as a veiled warning to Queensland not to impose broader travel restrictions like those she had fought in the past.

“I ask people to consider the fact that vast parts of New South Wales are completely unaffected,” Berejiklian said.

NSW Health Minister Brad Hazzard is from the northern beaches area and was tested, negative, for COVID-19 overnight. He will also have to cancel Queensland travel plans.

“I was heading up there on Christmas morning – I’m hoping I get a refund from Virgin if you’re listening,” Hazzard said during a media conference broadcast live.

Hazzard again took aim at Sydney-siders who had ignored the public health advice and failed to take proper precautions in recent weeks.

“The complacency is no longer creeping – it’s an avalanche,” Hazzard said.

“We are in the middle of a world-wide covid pandemic.”

Berejiklian said the management of crowds at some venues had been “absolutely appalling”. She also revealed international airline crews required to self-isolate at unsupervised hotels had been caught attending venues with Sydney-siders.

Blaming the flight crews, rather than the rules, Berejiklian said from Tuesday only two police-supervised hotels would be used by airlines, not 25 or 26 as is currently the case.

“There will be better compliance,” Berejiklian said.

“From Tuesday, there will be no chance of disobedience.”

NSW health authorities have yet to identify ‘patient zero’ or fully trace how the virus became a cluster.