South Australia has reported two new coronavirus cases - it's first in almost a week - but only one is considered active.
The active infection involves a woman in her 50s who returned from Pakistan earlier this month.
She spent two weeks in quarantine in Melbourne, where she returned two negative tests for COVID-19, but tested positive after arriving in Adelaide.
She will now spend at least another 10 days in quarantine.
The second case involves a woman in her 30s who arrived in Adelaide last month on a repatriation flight from India.
She also tested negative while in quarantine but subsequent serology testing indicated she had been infected at some stage previously.
Chief Public Health Officer Nicola Spurrier said both women weren't considered to be a risk to the wider community and only the woman from Pakistan was deemed to be an active case.
"I am not worried about these cases because they have occurred in a very confined way within quarantine or isolation," she said.
"But it is a reminder to people in South Australia that COVID-19 is still active in Australia."
Professor Spurrier has also praised the crowd at Monday's AFL game at Adelaide Oval which attracted a crowd of more than 13,000.
She said most fans did their best to keep physically distant from others and ground staff did a good job of managing the gathering.
The next match will be played on Saturday when 20,000 people are expected to watch Port Adelaide take on St Kilda.
While on Sunday a crowd of about 16,000 is likely for the match between Adelaide and Essendon.
Stadium Management Authority boss Andrew Daniels said some tweaks would be made this weekend to ensure everyone was kept safe, including the management of queues and access to oval gates.
"We'll ensure the entire Adelaide Oval is open so people will clearly be able to spread out," he said.
The new cases in SA on Wednesday took the state's total to 446 and came as Victoria reported a record 484 new infections, and NSW 16.
The increases interstate will ensure the state keeps its border restrictions in place as it moves to lift penalties for those who flout the rules.
South Australia's transition committee said the hard border closure with Victoria - which allows only essential travellers to cross - would stay, as would quarantine requirements for people from NSW and the ACT.
On Tuesday, new laws were also introduced to parliament to add jail time as possible penalties for breaching SA's border rules.