The state recorded another five cases on Thursday, bringing its total to 42, but health authorities have stressed there is still no evidence the virus is being spread within the community.

"As you can see, all of the cases in South Australia have either travelled from overseas, interstate or have been a close contact of a confirmed case," chief public health officer Nicola Spurrier told reporters on Thursday.

"That's very important for us in South Australia because it means that we still continue to have no sustained community transmission at this stage."

Professor Spurrier said of those who had contracted the virus, eight remained in the Royal Adelaide Hospital while another 11 were being treated at home.

She said the virus had been "relatively mild" in South Australia, and no one had needed intensive care treatment.

Closures and cancellations have continued across the state, with the Catholic Church in South Australia cancelling services including the Easter mass.

Baptisms, weddings and funerals will be allowed to proceed only if there are fewer than 100 people.

As buyers continue to stock up, the state's shops will be allowed to trade 24 hours a day Monday to Friday and for extended weekend trading hours to ensure access to supplies.

The deregulated shop trading hours will begin on Saturday and last for 30 days, the government said.

In anticipation of a further rise in cases, new hospitals will also be set up in Adelaide to treat coronavirus patients.

The two dedicated facilities will be established at the recently decommissioned ECH College Grove and Wakefield hospitals.

Premier Steven Marshall said the move would provide an extra 188 beds to manage an expected increase in the number of people needing hospitalisation.

"Both hospitals will assist in providing a greater level of protection for the wider community by minimising the incidence of the transmission of coronavirus," the premier said.

Health Minister Stephen Wade said both hospitals were in use until a few months ago and no structural works were required.

He expected both to be operational in April.

Australian Associated Press