It comes after Australia slammed its borders shut to travellers from nine southern African countries impacted by the variant, including South Africa, Lesotho, Botswana, Zimbabwe, Seychelles, Mozambique, Namibia, Eswatini and Malawi.
NSW Health Minister Brad Hazzard told 7 News the woman "has essentially been out in the Central Coast area".
"This particular lady came in before the new arrangements, that is transferring to a health hotel, so she has been out in the community and health is now investigating that," he said.
It brings the total number of Omicron cases nationwide to six.
'Get tested immediately': 11 NSW venues exposed to Omicron
NSW Health has released a string of venues visited by the countries latest Omicron case, with the department declaring testing "strongly indicates" the woman has the new strain.
The woman, who is fully vaccinated, arrived in Sydney on flight QR908 from Doha to Sydney on November 25 and travelled by private car to the Central Coast. She had been in southern Africa, and is now isolating at home on the Central Coast.
"Everyone on the flight is considered a close contact and will need to get tested immediately for Covid-19 and isolate for 14 days, regardless of their vaccination status," the department said in a statement.
A flight crew walk through the terminal at Sydney Airport. Photo / AP
"NSW Health is contacting all passengers and flight crew to advise them of their isolation requirements.
"NSW Health advises a number of venues were visited by the traveller in Sydney and on the Central Coast before NSW Health directed travellers from southern Africa to go into isolation."
The venues include:
• Coles, Top Ryde Shopping Centre: Friday, November 26, 9.30am to 10.45am
• Target Parramatta, Westfield Parramatta: Friday November 26, 10.45am to 11am
• H&M Parramatta, Westfield Parramatta: Friday November 26, 11am to 11.15am
• Woolworths, Wadalba: Friday November 26, 7.30pm to 8.15pm
• Aldi, Toukley: Saturday November 27, 4.45pm to 5.45pm
Anyone who attended those venue at the times listed is a casual contact who must immediately get tested and isolate until a negative result is received.
