Chief Health Officer Jeannette Young said the case involved a woman who arrived on December 22 and was immediately placed into hotel quarantine.

"Genome sequencing has come back to show that she has this new variant that has been picked up in South Africa that is thought to be more contagious," she said.

The woman was transferred via ambulance to the Sunshine Coast University Hospital.

Health Minister Yvette D'Ath said while other jurisdictions had detected a UK variant of the virus, this was the first time the South African strain had been confirmed in Australia.

"We are absolutely confident that all proper measures were taken at the hotel and in the transfer, and of course at the hospital in relation to this positive case," she said.

There were two new cases recorded in the state overnight, both acquired overseas and detected in hotel quarantine.

Routine wastewater testing has also returned positive results for viral fragments of COVID-19 in seven Queensland locations.

Fragments were detected in treatment plants in Victoria Point, Oxley Creek, Goodna, Fairfield and Redcliffe as well as Cairns North and Nambour.

Dr Young said continued positive sewage results, collected on December 22 and 23, are particularly concerning given the NSW cluster.

"We are concerned given this is the first time we've had seven locations test positive at the same time," she said.

Queensland Health has also confirmed two crew members from a superyacht that arrived in Cairns four days before Christmas no longer have active COVID-19 infections.

A man in his 30s and a woman in her 20s had initially tested positive after the Lady E arrived on December 21, following a two-week sea journey from the Maldives.

Further testing found the pair were carrying antibodies from an old recovered infection.

"The blood tests confirm there is no active COVID-19 infection," Queensland Health said in a statement on Tuesday.

"Both will remain in quarantine and full isolation from the wider community until early January."

All other crew members have returned negative test results but will continue to isolate either on the yacht or onshore.

The captain of the Lady E, James Kennedy, said he was grateful for the effort authorities had gone to on behalf of the crew.

Australian Associated Press