There are fears the potentially dangerous Omicron variant could already be in Australia after a traveller from South Africa tested positive to Covid-19 in the Northern Territory.
Genomic sequencing is urgently underway to determine which strain the passenger, who was on a repatriation flight, is infected with. The heavily mutated strain was discovered in South Africa earlier this month.
The results are expected to be processed by Monday.
Health Minister Natasha Fyles told reporters on Saturday the traveller has been in supervised quarantine at the Howard Springs Quarantine Facility, south of Darwin, since arriving in the NT on Thursday.
"So there is a very low risk to the community and we wish that person well," Ms Fyles said.
The passenger, who tested positive on Friday, is one of two new cases recorded in the state. The other is a man in his 50s from Katharine who is a household contact of an existing case.
He has also been housed at Howard Springs during his entire infectious period and is considered a non-risk.
Omicron has been declared a variant of concern by the World Health Organisation (WHO).
The WHO has warned the new variant may spread more quickly than other strains and poses a much higher risk of reinfection because it has double the number of mutations as the deadly Delta variant.
Cases of Omicron have so far been found in Belgium, Botswana, Israel and Hong Kong.
Katherine moves out of lockdown
The new infections bring the Katherine Covid cluster to 53 cases in total as the town emerges out of lockdown, which lifted at 12pm on Saturday.
"So anyone that is fully vaccinated in the region is now free to go about their daily business," Ms Fyles said.
"They will need to wear a mask and ... please make sure to check in when you are out and about."
Unvaccinated residents remain subject to lockdown orders until December 7, with the community currently 78 per cent fully immunised.
Man escapes quarantine
Meanwhile, a man who broke out of quarantine at Howard Springs has been caught at a bar in Darwin.
Police say the 27-year-old, who was on day 13 of his isolation period, scaled the fence before he was picked up by a white ute on Friday night.
He was later found at a licensed venue on Mitchell St and taken back to the quarantine facility, where he returned a negative Covid test result.
Investigations into the ordeal are underway, with officers working to track down the people who helped the man escape.
Ms Fyles said practices at the facility would be reviewed, adding she was "extremely disappointed" at what happened.
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