The MV Sofrana Surville was blocked from docking in Brisbane after New Zealand warned it could be carrying a mystery strain of the virus.

Testing found two of the Sofrana's 19 crew members were infected but more work is required to find out if the stain is new.

Deputy Premier Steven Miles said genomic sequencing on the suspected mystery strain would take about a week and reveal its origins.

"Given (the cases) have come off a ship that has been in other countries it's highly likely to be a different strain ... (to) the current strains within Australia," he told reporters on Friday.

Dr Miles said it was normal for viruses to mutate and there were numerous strains already circulating in the country.

The Sofrana left New Zealand earlier in the month with fresh crew from the Philippines before stopping at Noumea in New Caledonia.

It then sailed for Brisbane.

New Zealand requested Australian health officials perform genomic sequencing on the Sofrana's crew's virus strain after an engineer who had previously worked on the ship tested positive in Auckland.

Queensland health officials completed 4780 tests in the 24 hours to Friday morning.

The state has six active cases and it has been 43 days since the last case was diagnosed in the community.

Dr Miles said it was likely an announcement would be made about Queensland's border reopening to NSW late next week.

Asked when Victorians would be free to travel to Queensland, Dr Miles said it would be after heath restrictions in that state were eased and several incubation periods had been completed.

"To see what effect that has," he said.

"We haven't put a date on our road map."

Australian Associated Press