The new cases came after almost 25,000 tests were conducted in the preceding 24 hours.
Hospitalisations rose to 164, with 16 of those in intensive care.
About 80 per cent of ICU patients are unvaccinated, despite the unvaccinated making up only 7.3 per cent of the population.
Two more health workers tested positive.
Some 608 health workers are either positive or in isolation due to being a close contact, from a workforce of 53,000.
“That number is steadily increasing and something we’re very concerned about,” Premier Steven Marshall told reporters on Saturday.
The five deaths included a person aged in their 50s and another in their 60s, one in their 70s and two aged in their 90s.
Three new cases were uncovered in remote Indigenous communities, including a person who had relocated from Adelaide.
But Marshall said it was pleasing that 270 community members in Amata, in the APY Lands, had tested negative after two cases were reported there earlier this week.
Another 30 results are expected later on Saturday.
Marshall confirmed aged care and disability workers will join healthcare workers in needing a third vaccine dose to be considered fully vaccinated. That mandate will apply from January 30.
He warned the government was considering applying the third-dose mandate to other workforces, including childcare.
The doubling of new COVID-19 cases in Victoria today to 51,356 is based on the delayed reporting of cases that are up to a week old, according to the state’s health minister.
Saturday’s case number is more than double Friday’s figure, with almost half (26,428) the positive cases revealed using new rapid antigen test (RAT) reporting.
But Health Minister Martin Foley told reporters the figures were inflated due to the introduction of the RAT reporting system, and only about a quarter (5923) of Saturday’s positive RAT results were from the latest 24 hour reporting period.
New South Wales reported another 45,098 cases on Saturday, including 32,000 in Sydney health districts and 37 in prisons.
Authorities there reported the deaths of four women and five men, aged in their 50s, 70s and 90s.
Local News Matters
Media diversity is under threat in Australia – nowhere more so than in South Australia. The state needs more than one voice to guide it forward and you can help with a donation of any size to InDaily. Your contribution goes directly to helping our journalists uncover the facts. Please click below to help InDaily continue to uncover the facts.