COVID-19 restrictions introduced across South Australia in December have significantly slowed the spread of the virus based on the latest data, the state government says.
When the restrictions, including tougher density rules and caps on family gatherings, were imposed on Boxing Day, infections in SA were doubling every 2.4 days.
But by January 9, that had widened to every 8.2 days.
"This new set of data shows the tough calls we made on Boxing Day were critical in slowing our infection rate to ensure our health system is not overrun," Premier Steven Marshall said.
"The data also shows how South Australia has slowed our infection rate far more quickly than other states currently facing the Omicron outbreak.
"While I know these restrictions have been incredibly tough on certain sectors, putting them in place has meant we have kept control of cases."
On Thursday, SA also introduced new rules for close contacts of cases to have rapid antigen tests rather than a PCR swab.
But anyone who tests positive will be required to report the result through an online system. Failure to report could result in a $1000 fine.
Mr Marshall said the decision to make reporting mandatory was about getting as much real data into the system as possible to help model the likely trajectory of the current outbreak.
"We're keen to track every single one of those results," he said.
"While we think that 95 per cent of people would do the right thing, getting as many positive results into the system just improves that data."
Close contacts will be provided with two free RATs which they should use on days one and six while isolating.
The tests will initially be provided through one site established in the Adelaide parklands but more locations will follow.
The parklands site has the capacity to handle about 13,000 people a day and quickly attracted a long queue on Thursday morning.
Australian Associated Press
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