The South Australian Government's latest modelling shows the state will reach the peak of the current COVID-19 wave next week.
South Australia is currently recording about 1,000 new COVID cases per day.
In a late afternoon press conference, Health Minister Chris Picton said the latest data showed cases would start reducing ahead of the Christmas and New Year period.
"The good news is ... that the prediction is that we will start to see cases reduce towards Christmas, which is excellent news I think for people's planning for the festive season," he said.
But Mr Picton said it was crucial precautions were taken to protect vulnerable people in the community.
"That is particularly true for aged care, hospitals, people who are disabled, people who are more susceptible to worse effects from COVID-19," he said.
"We are asking people to be conscious of them, to not go to hospitals and aged care if you have symptoms, particularly to wear masks around vulnerable people in our community and in vulnerable settings."
Chief Public Health Officer Nicola Spurrier said people should also think about wearing masks when in crowded indoor areas, including at the Black Friday retail sales.
"I'm sure Rundle Mall is hoping that it will be full of people looking for those Christmas gifts, as well as taking advantage of the sales … I would be saying to people have your mask in your pocket and pop it on when you are in that very crowded space," she said.
"The other place is of course public transport ... there might be someone on the bus who might be on chemotherapy or have other vulnerabilities.
"This is only for a couple of weeks, just as we get over that curve and start coming down the other side.
Professor Spurrier said hospitalisations were not expected to be as high as they were during previous waves.
"We are expecting much lower numbers of admissions compared to all of the other three waves in our state which is very good news for our health staff," she said.
"The reasons behind this is of course we have a very well-vaccinated community."
The government urged the public to make sure they are up-to-date with their vaccinations, and encouraged those eligible to plan how they will access anti-viral treatments if needed.
