States and territories around Australia have responded to Adelaide’s northern suburbs cluster by closing down borders, in some cases just days after they reopened.
Queensland, Northern Territory, Western Australia, Victoria and Tasmania have all declared South Australia to be a COVID-19 hotspot.
Those entering the Northern Territory from South Australia will now have to undergo a mandatory 14-day supervised quarantine upon arrival.
Anyone arriving in the territory from SA on Monday or Tuesday will not have to pay the $2,500 quarantine fee.
However, those arriving from Wednesday will need to quarantine at their own expense.
Those entering Western Australia from South Australia will also need to quarantine, the new rules coming into effect just 48 hours after border restrictions were lifted.
People entering WA will be permitted to self-quarantine and will not be subject to a fee. The change will bring arrivals from SA into line with the same restrictions on those arriving from Victoria and New South Wales.
Tasmanian Premier Peter Gutwein also announced on Monday morning that people arriving from SA will be subject to self-quarantine.
Queensland has effectively closed their borders to SA from 11:59pm tonight, with those entering subject to quarantine on arrival.
Victorian premier Daniel Andrews has declared SA to be a COVID hotspot, but stopped short of closing its border.
Meanwhile, New South Wales Premier Gladys Berejiklian has confirmed that the state will not be changing their border restrictions with SA for the time being.