The ACT will reintroduce stricter quarantine rules for international arrivals, as the territory moves to prevent a new COVID-19 variant of concern first identified in South Africa from entering the territory.
All international arrivals into the ACT after 11.59pm on Saturday will need to quarantine for three days, in a move health authorities said was precautionary.
Anyone in the ACT who has been in South Africa, Lesotho, Botswana, Zimbabwe, Mozambique, the Seychelles, Malawi, Namibia or Eswatini in the past 14 days needs to get a PCR test for COVID-19 and quarantine immediately.
People who have spent time in those countries in the last 14 days will need to quarantine at their place of residence or accommodation until two weeks has passed since they were last in the listed country.
Those travellers will also need to fill in a declaration form, and their household members will need to quarantine with them.
ACT Health said in a statement late on Saturday night no cases of the Omicron variant of concern of COVID-19 had been identified in the territory. The ACT reported seven new COVID-19 cases on Saturday.
"ACT Health is monitoring this situation closely and will continue to provide updates. Quarantine requirements for returning international travellers will be reviewed on Tuesday 30 November, to determine whether existing quarantine requirements should be extended," health officials said.
Federal Health Minister Greg Hunt earlier on Saturday announced Australian citizens entering Australia who have been in South Africa, Lesotho, Botswana, Zimbabwe, Mozambique, Namibia, Eswatini, Malawi, and the Seychelles in the past two weeks must do two weeks of mandatory hotel quarantine.
"There are no known cases of the Omicron variant in Australia," Mr Hunt said.
"We've taken precautious action in the past, we've taken early action in the past. We are doing that again."
The new variant, named Omicron by the World Health Organisation on Saturday morning AEDT, first emerged in Botswana and has been detected in South Africa, Hong Kong, Israel and Belgium.
It has double the number of mutations as the Delta variant that sparked a third wave of outbreaks and lockdowns in Australia this year.
Chief medical officer Paul Kelly said Omicron was spreading quickly, but it wasn't clear that it caused more severe symptoms than existing strains or if it could evade vaccine immunity.
In a statement on Friday, the World Health Organisation designated it as a "variant of concern," naming it "omicron" after a letter in the Greek alphabet.
After convening a group of experts to assess the data, the United Nations health agency said that "preliminary evidence suggests an increased risk of reinfection with this variant" as compared to other variants.
Concern over the new variant prompted a wave of changes to state border regimes on Saturday evening.
In NSW, arrivals who've been overseas anywhere in the past 14 days must isolate at home for 72 hours pending further advice.
The isolation requirement is two weeks for flight crews, unless they leave the country first.
Anyone already in the state's who been in one of the nine African countries in the past 14 days must isolate for two weeks, be tested, and contact NSW Health.
Western Australia will immediately tighten its border with South Australia, with arrivals from that state required to isolate at home for 14 days and be fully vaccinated.
Premier Mark McGowan said the uncertainty around the new variant meant his state needed to have protections in place for states with relaxed international borders.
WA already has strict border controls in place for NSW, Victoria and the ACT.
Mr McGowan said he wouldn't yet be changing his plan to open interstate borders when his state's vaccination levels are higher.
South Australia in turn will force international arrivals into two weeks of quarantine, four days after allowing seven-day quarantine for Australian citizens.
Interstate travellers must now provide evidence of a negative test taken before their arrival.
Tasmania will ban travellers from southern Africa until they have completed 14 days of supervised quarantine, and the required testing, in the mainland state where they arrived.
- with AAP
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