Australian states are taking swift action after the discovery of the first mutated COVID-19 strains making their way into the country.

On Friday, New South Wales identified six cases of the UK strain and four of the South African strain in returned travellers.

“Further testing is under way to confirm these results, but as a precaution the 16 people who were accompanying that flight have, as a precaution, [been] moved to [NSW accomodation facilities],” NSW Chief Health Officer Kerry Chant said.

“They will be cleared when they are assessed to be no longer infectious.”

The strains, believed to be hyper infectious, are further cause for concern as the state battles to suppress the Berala and Avalon clusters.

“There are concerns that this South African strain does share a similar mutation from the UK that may be associated with increased transmissibility. That is why we are taking a very cautious approach there,” Chant said.

It comes just a few hours after Queensland revealed that it had identified one case of the UK strain in the community.

While Queensland Premier Annastacia Palaszczuk issued a three-day lockdown of Greater Brisbane in response to the finding of the “incredibly infectious” strain, other states are already taking their own precautions.

On Friday, Tasmania closed its borders to Brisbane residents with Premier Peter Gutwein telling those who had already arrived that they are “required to stay at home and must not travel”.

“If they do not have a suitable premises they will be placed into a government quarantine hotel,” Gutwein said in a statement.

While New South Wales Deputy Premier John Barilaro said his state wouldn’t shut the border, visitors from Brisbane would be required to isolate.

“If you are in the midst of travelling from Brisbane, as we speak, to New South Wales and you come from those [Greater Brisbane] areas, we expect you to abide by the isolation rules that would have applied to you as if you stayed Brisbane,” he said.

“If you have visited Brisbane and you are on your way to NSW, isolation rules will apply to you. If you are already in NSW and you have travelled to New South Wales from those locations since… the 2nd of January, we expect you to stay isolated.”

South Australia took a different tact again, following Friday’s National Cabinet meeting, with South Australia Premier Steven Marshall revealing Palaszczuk had asked all states to treat Brisbane as a hotspot.

Marshall said that a 14-day quarantine period would be mandatory for Brisbanites arriving from midnight, while those already arrived would be subject to three tests during their stay.

“From today anybody that comes from Greater Brisbane area into our state today will require day one, [day] five, and [day] 12 testing,” South Australia Chief Public Health Officer Nicola Spurrier said.

“They are not required to isolate, but they need to have that testing and to facilitate this we have already made plans to set up, additional testing at the Adelaide Airport.”

Victorian Premier Daniel Andrews meanwhile said he’d update his state shortly on what action would be taken, but asked Brisbane visitors to reconsider travelling.

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