Investigations into the precise cause of transmission are ongoing, she said.
Professor Spurrier said discharged returned travellers on level three of the Playford Hotel during the period of concern must now isolate for a further two weeks.
The group includes 10 South Australians who will be given the option to quarantine at home if deemed suitable.
READ MORE
Prof Spurrier stressed most medi-hotel staff working at the time of the suspected leak had undergone daily testing, although five still need to be followed up.
SA authorities earlier barred travellers from entering the state if they had visited any of Victoria s high-risk exposure sites, with few exceptions.
South Australian Premier Steven Marshall today became the first person in the state to receive the coronavirus vaccine, followed by Chief Public Health Officer Nicola Spurrier.
Others among the first 150 frontline health workers to receive the Pfizer vaccine at Royal Adelaide Hospital this morning included a medi-hotel nurse, a security guard and a police officer.
Health Minister Stephen Wade and Police Commissioner Grant Stevens also rolled up their sleeves to receive the jab.
Join Will McDonald for the return of Adelaide s 9News at 5pm today. Get the latest from the team that s live and local, weekdays at 5pm and nightly at 6pm on Channel 9.