What's what with COVID-19 in Australia on December 24, 2021

Jetstar, Qantas and Virgin abruptly axed dozens of flights across Australia on Friday.

Sky News has reported 35 flights were cancelled between Sydney and Melbourne alone, while another 10 from Sydney to Brisbane didn't get off the ground as well as four between Sydney and the Gold Coast.

But other reports have estimated almost 100 flights have been affected due to a lack of ground staff. Many workers have been forced into COVID isolation after being identified as close contacts, particularly in Sydney.

Meanwhile, Australians will have their wait for a COVID-19 vaccine booster reduced as authorities scramble to slow the spread of the Omicron variant.

The number of new COVID-19 infections in NSW has topped 5000 for the second day in a row, swamping contact tracers, overwhelming testing sites and affecting domestic flight schedules as authorities reintroduce mask rules.

Some 5612 people were diagnosed with the virus in the 24 hours to 8pm on Thursday from more than 164,000 tests.

While the number of cases dropped by 103 from the record high of the day before, the number of tests increased by more than 3600.

One death was also reported - a fully vaccinated woman in her 90s who acquired COVID-19 in a Lakemba aged care facility.

Queensland's active cases have risen to almost 1400 with 589 reported overnight. Three patients were in hospital with mild to moderate symptoms.

A total of 268 infected people are being managed in their homes and 110 people are in hospital for other reasons.

Since mid December, 32 of Queensland's 77 local government areas have recorded a case of COVID-19.

Victoria has reported 2095 new COVID-19 cases and eight deaths after the state government told residents young and old to don masks during the holiday season.

Friday's daily case figure shows infection numbers are slowly climbing towards the high recorded on October 22 when the state recorded 2160 cases.

It's also pushed up active infections to 15,471.

A total of 397 patients are in hospital, including 75 who are actively infected with the virus and in intensive care, with 40 on ventilators.

COVID-19 testing clinics in the north of the state will continue to operate over the holiday period while the government awaits health advice on the use of rapid antigen tests.

The state's COVID numbers doubled overnight and demand for PCR testing high, the Tasmanian government has advised asymptomatic members of the community, with COVID concerns, to purchase rapid antigen tests as a further safeguard.

South Australia has reported another record of 688 new COVID-19 infections amid fears for the state's health system if action is not taken to slow the spread of the new Omicron variant.

Chief Public Health Officer Nicola Spurrier said eight people were currently in hospital with one man in his 30s on a ventilator in intensive care.

Plans to lift restrictions on December 28 have been put off until next year due to increased concerns over the Omicron strain.

The SA Premier encouraged people to work from over the next four weeks.

The ACT has reported a spike in COVID-19 cases with 102 new infections on Friday, the first time the territory has recorded case numbers in the hundreds.

It's a jump from 85 cases on Thursday and 58 the day before.

The new cases bring the active total to 334.

The Northern Territory has detected 10 new COVID-19 cases as infected travellers continue to arrive in the territory.

One of the cases is linked to the current community outbreak, bringing the cluster to 132 infections.

The other nine are recent arrivals in the NT.

Four new local cases of COVID-19 have been recorded in Western Australia after a visiting backpacker attended nightclubs and restaurants while infectious.

One is a close contact and three are casual contacts of the original case at an event at the Perth Mess Hall in Northbridge on Sunday, Premier Mark McGowan said.

Anyone who attended the event must get tested and self-quarantine until January 3 under changes to rules announced on Friday morning.

The 25-year-old man's infection was picked up on Thursday.

- with AAP