Eleven people have died with COVID-19 in South Australia as the state reported another 3777 infections.
Premier Steven Marshall says 290 people are in hospital with the virus, but 47 of those were admitted for other reasons.
There are 29 people in intensive care with nine on ventilators.
Among the 11 deaths, five occurred in aged care centres.
The new infections reported on Thursday remained below the state's seven day average of 3949.
Mr Marshall said South Australia had finally reached the 90 per cent double-dosed vaccination target for those aged 12 and over, a level initially expected in late December.
He also confirmed that South Australians who tested positive for COVID-19 would continue to quarantine for 10 days.
Suggestions the isolation requirement should be cut to five was not something SA would sign up to, the premier said.
"We know that patients still have symptoms after five days, in fact after seven days," he told ABC radio.
"We know that from the surveys that we take. We don't want a whole pile of people who are infectious post contracting this disease out getting more people infected."
Mr Marshall said surveys and checks on people with COVID-19 had confirmed a large number of people still had symptoms after day five.
"We would just be literally lighting a fire in South Australia if we allow them to leave quarantine after five days," he said.
"They would just be out there infecting other people and then we'd have another wave in South Australia."
The premier said a shift to a seven-day quarantine period was possible at some stage, but at the moment he believed SA had the balance right.
"We do have a more prudent approach in South Australia but I think over the longer term that's proved to be the most successful," he said.
