Almost 150 people have arrived in NSW from southern African countries where the new Omicron COVID-19 variant is running rampant, with three possible cases among them.
Genomic testing on Sunday confirmed two overseas travellers who arrived in Sydney have been infected with the new coronavirus variant.
Both passengers were asymptomatic when they arrived on Saturday night and are in isolation in the Special Health Accommodation. Both are fully vaccinated.
NSW Premier Dominic Perrottet said a third person possibly has the variant, with 141 people having come to the state from the nine countries of concern over the past 24 hours.
All have been sent to hotel quarantine for 14 days.
Although he has ordered all international arrivals to quarantine at home for 72 hours, Mr Perrottet insisted the NSW international and state borders would remain open.
“Ultimately we need to open up to the world (and) we need to do so safely,” he told reporters on Monday.
“We don’t need to have a knee-jerk reaction, we need to have a proportionate and balanced response to the situation that’s in front of us.”
The three-day quarantine order is on top of a federal government requirement for travellers to enter quarantine for two weeks if they have been in South Africa, Lesotho, Botswana, Zimbabwe, Mozambique, Namibia, Eswatini, Malawi or the Seychelles in the past 14 days.
Mr Perrottet also stressed NSW was better equipped to confront new variants.
“We’ve got to learn to live alongside the variants of the virus that come our way,” he said.
“And the vaccination rate here is one of the highest in the world.
“That is not the case in the southern African nations.”
The premier has said there are no plans to adjust the state’s reopening roadmap, so restrictions will still ease for the unvaccinated on December 15.
Meanwhile, the state added 150 new infections to its caseload on Monday.
For the fifth consecutive day, no new deaths were reported.
Hospitals are treating 170 patients, five more than the previous day, including 25 people in intensive care.
NSW is 94.5 per cent single-dosed for everyone 16 and over, while 92.4 per cent are fully vaccinated.
Of 12- to 15-year-olds, 81.3 per cent have received one jab and 76.5 per cent both.