NSW Health said the passengers, who landed in Sydney on Sunday from southern Africa, were both fully vaccinated and are now isolating in the Special Health Accommodation.
Everyone who was on board Singapore Airlines flight SQ211 is now considered a close contact and will need to immediately get tested and isolate for 14 days, regardless of their vaccination status.
“NSW Health is contacting all passengers and flight crew to advise them of isolation requirements,” a statement issued on Monday evening read.
It brings the total number of confirmed cases of Omicron in NSW to four.
A man in his 30s, who was on a repatriation flight to Darwin, has also tested positive to the new strain.
He has been in the Howard Springs quarantine facility since his arrival.
It’s still not known whether the new variant of concern is more contagious, more likely to cause serious illness or more able to evade the protection of vaccines.
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