Adelaide, Nov 23 (IANS): South Australia (SA) Premier Steven Marshall on Monday said that the state has avoided a second Covid-19 wave by acting on an outbreak early.

In a statement, Marshall said the state could have been facing 100 new cases per day in December if swift action was not taken to suppress the outbreak linked to the cluster in the northern suburbs of Adelaide, capital city of the state, reports Xinhua news agency.

The state-wide "circuit breaker" lockdown ended at midnight on November 21, three days earlier than previously planned.

It reported one new case on Monday, bringing the total number of infection associated to the cluster to 27.

"We have avoided this second wave, avoiding 100 cases per day by mid-December," Marshall said.

"I'm feeling very positive and very optimistic that and as we head into Christmas that we will be experiencing newfound freedoms and celebrating well, with all of our family and friends."

Nicola Spurrier, South Australia's Chief Public Health Officer, said the new case had been in quarantine since November 16.

And the woman had returned two negative tests before testing positive on this Monday morning.

"It absolutely tells us that anybody who has been asked to be in quarantine needs to be in quarantine for the whole 14 days because there are people who have that very much longer incubation period," Spurrier said.

Australia has so far confirmed 27,821 coronavirus cases and 907 deaths.