A South Australian child under the age of two with COVID-19 has died, as the state records 1374 new infections.
Premier Steven Marshall confirmed the death on Thursday afternoon and said it would be referred to the coroner.
"The family is obviously in a great deal of distress at the moment," Mr Marshall told reporters.
"I can say that the cause of death has not been determined, but this was a child under the age of two who was COVID positive."
Mr Marshall said he would not be giving details about whether the child was in hospital.
The child's death comes amongst 99 children and 81 teenagers who are included in Thursday's infection tally.
There continues to be 37 people in hospital, with four in intensive care including one on a ventilator.
Of the people in hospital, there are six children, four people in their 20s, five in their 30s and four in their 40s.
There were 23,420 PCR tests processed on Wednesday, returning 1374 positive cases compared to 1472 the previous day.
"So a slight reduction on the day before but these numbers are likely to bob around for some time," Mr Marshall said.
The new cases brought the total number of infections since November 23 to over 8000. More than four in five cases continue to be the new Omicron variant.
There are more than 7400 cases in home quarantine and 110 in supervised quarantine.
Following Thursday's national cabinet meeting, Mr Marshall said the definition of a close contact would be narrowed to a household or intimate contact of an infected person.
There will be exceptions such as "in more vulnerable communities and also where there is a known significant transmission event," Mr Marshall said.
He also urged people not to flood testing sites to ease strain on the system and that national cabinet had agreed to start relying more on rapid antigen tests.
The state has a stockpile of about 780,000 rapid antigen tests, with another nine million on order, needed for use in health settings and high-risk settings.
Mr Marshall urged retailers to "do the right thing" on pricing RATs for the general public.
About two-thirds of people currently getting PCR tests in the state were asymptomatic, he said.
"These people, really, quite frankly, should not be in the line unless they were close contacts of somebody who was a positive case," Mr Marshall told reporters.
"We really do want to free up our capacity for testing for those people who have symptoms."
With the next three days set to reach temperatures above 35C in Adelaide, testing sites are also changing their operating hours.
Across metropolitan Adelaide, sites will be open between 6.30am and 10.30am, then close until 5.30pm, staying open until 8.30pm or 10.30pm depending on the location.
In regional SA, testing sites at Bordertown, Mount Gambier and Port Augusta will follow a similar pattern, while others will only be open for the morning or from 5.30pm.
Isolation periods for positive cases and their close contacts will also change on agreement by the national cabinet and Mr Marshall reminded South Australians the state was no longer chasing COVID-zero.
"We're at a different stage now and so we are no longer asking casual contacts to isolate," he said.
Narrowing the isolation periods and definition of close contacts means vital work forces, such as aged care, can continue, he says.
Australian Associated Press
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