Quarantine rules will be relaxed to seven days for fully vaccinated close contacts in Queensland, as the state reported 86 new COVID-19 cases on Tuesday.
The case numbers were the highest daily total reported in Queensland since the pandemic began in 2020.
Under the new rules, fully vaccinated people deemed as close contacts of COVID-19 cases would only need to quarantine for seven days and have a test on days one and five, or if they developed symptoms.
The change from 14 to seven days was due to come into effect on January 1, but were brought forward to 1am on Wednesday.
It still meant anyone deemed a close contact this week would miss Christmas gatherings with family and friends.
There would be no reduction in quarantine requirements for unvaccinated close contacts.
Tuesday's daily total of 86 was a jump from the 59 cases reported in Queensland on Monday, which Chief Health Officer John Gerrard said followed the expected trend of cases doubling every 48 hours.
"We have 61 confirmed cases of Omicron in Queensland," Dr Gerrard said.
"We're seeing about two cases of Omicron diagnosed for every one case of Delta.
"Omicron has become the dominant virus here in Queensland."
There were 269 active COVID-19 cases in Queensland on Tuesday, with one patient, who has other medical conditions, in intensive care as a precaution.
In the past 24 hours, there were more than 34,000 COVID tests in Queensland.
South Australia has scrapped the requirement for a test for NSW, Victoria and ACT residents entering that state if they are asymptomatic.
It came amid lengthy delays at COVID testing clinics across Sydney due to travellers requiring a negative test result before crossing domestic borders ahead of Christmas, with some sites turning people away due to a shortage of available tests.
But Dr Gerrard said Queensland's measures aimed to slow the spread of the virus to reduce strain on hospitals.
Police Commissioner Katarina Carroll said there had been more than 225,000 applications for border passes from hotspots, including NSW and Victoria.
But she said many people were attempting to enter Queensland by road or plane without having a negative PCR test within the 72 hours before they arrived.
"We are seeing people actually flout this," she said.
In the past 24 hours, 36,271 vehicles entered Queensland and 325 were turned around.
In Queensland, 89.77 per cent of people aged 16 and older have received one dose of a COVID-19 vaccine, while 84.70 per cent were double-dosed.
Queensland was expected to hit 90 per cent first dose vaccinated later on Tuesday.