South Australia has reported two new cases in its latest cluster of local COVID-19 infections but both are already in hotel quarantine.
The new cases take the current outbreak to 21 since it first emerged more than a week ago.
One case involves a woman in her 80s, who is the wife of a man who also has the virus, and the second is a man in his 40s, whose two adult children previously tested positive.
Chief Public Health Officer Nicola Spurrier said the continued emergence of cases in the current outbreak emphasised the need for those people still in home quarantine to complete their full 14 days and for other people to follow the restrictions in place.
"Even at this late stage, it is still possible for people to become positive," she said.
"You can be highly infectious, even if you haven't had any symptoms yourself."
Professor Spurrier said the growth in the number of cases in NSW also continued to pose a real risk to South Australia with a significant number of people seeking to return to the state.
She said all options were being considered to bring those people back.
Premier Steven Marshall said some exemptions had already been granted but officials would continue to take a careful approach.
"We've really got to manage this risk at the moment. My primary concern is the health of all South Australians," the premier said.
"We'll manage these applications but we'll do it in a prudent way."
At the same time, the transition committee has decided against any immediate change to border restrictions which prevent most people in NSW and Victoria coming to South Australia.
The state's so-called Modbury cluster of coronavirus cases began with an 81-year-old man who recently arrived in Australia from Argentina and was quarantined in Sydney before travelling to Adelaide, where he tested positive.
It prompted a week-long statewide lockdown which was lifted on Wednesday.
With shops and other venues back open for business, Mr Marshall urged people to continue to take care but to also get out and support local traders.
SA virus restrictions include the mandatory use of masks in most situations, including in shopping centres and secondary schools.
All food and drink consumption must be seated and dancing and singing remain banned.
Family gatherings are limited to 10 people, although weddings and funerals can have up to 50.
Sports training has resumed but competitions will be delayed until August 7.
Australian Associated Press