Australia was put back on high alert on Monday (November 16), as the state of South Australia ended a months-long streak of no locally-transmitted COVID-19 infections.
A new virus cluster in South Australia has been linked to 17 infections so far, after a worker from a quarantine hotel infected family members.
The news has stoked fears of a new virus hotspot within the country.
South Australian Premier Steven Marshall:
"I would like to advise all inbound international flights into Adelaide have now been suspended at our request for the remainder of this week. Our priority is ensuring that we have enough medi-hotel capacity to meet any local quarantine requirements. This morning I received a call from the prime minister and I accepted his offer for increased support from the Australian Defence Force."
It's prompted neighboring Western Australia to order mandatory testing and self-isolation for 14 days for new arrivals from South Australia.
The island state of Tasmania also ordered immediate self-isolation for South Australian arrivals, while the Northern Territory will now mandate supervised quaratine.
Meanwhile Australia's two most populous states, New South Wales and Victoria, have yet to announce any changes to border controls.
Ever since Victoria emerged from a lengthy lockdown earlier this month to contain its own outbreak, Australia had previously recorded several days of no new locally transmitted COVID-19 infections.