Five new cases of coronavirus have been confirmed in South Australia, bringing the state’s total 42.

One of those who tested positive has been identified as having travelled from interstate.

The other cases include three overseas travellers and one person who had close contact with a previously diagnosed case of COVID-19.

“We continue to have no sustained community transmission at this stage,” SA Health’s Dr Nicola Spurrier said.

SA Health says two of the cases, a man, and woman both in their 60s, had recently returned from the US.

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Play Video Qantas and Jetstar will suspend international flights from late March after the Governments new advice on overseas travel. Qantas and Jetstar will suspend international flights from late March after the Governments new advice on overseas travel.

The domestic traveller, in her 20s, had recently returned from Queensland and a man in his 40s had returned from the Czech Republic.

The fifth new case is a man in his 20s, who was a close contact of a previous case.

Unprecedented changes

On Monday, sweeping changes to the state’s retail trading laws were announced in a bid to keep supermarket shelves stocked during the pandemic.

Trading hours will be deregulated across the state, giving supermarkets the option to trade 24 hours a day on weekdays.

Employees of an IGA supermarket are seen unpacking stock outside their store in North Melbourne, Wednesday, March 18, 2020. Credit: JAMES ROSS / AAPIMAGE

Shopping hours will also be extended on weekends from 12am to 9pm on Saturdays and 9am to 9pm on Sundays.

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The temporary trade times will begin on March 21 and run until April 19.

During the extended trading times, employees cannot be forced to work the additional hours but can do so voluntarily.