South Australia has gone four days with no new coronavirus cases linked to the concerning Parafield cluster that emerged in November.

The cluster remains at 33, with only 10 of those still considered active infections.

About 1000 close contacts are still in quarantine but that number has dropped significantly from a high of almost 6000.

More than 6700 tests were carried out on Tuesday, taking the total conducted in SA since the start of the pandemic to almost 740,000.

The results are expected to strengthen SA’s case for Queensland to join with other states in dropping its remaining border restrictions.

On Tuesday, SA introduced a new QR check-in system, a key part of the push to ease local coronavirus restrictions in the lead-up to Christmas.

Chief public health officer Nicola Spurrier said it was a “game-changer” for staff trying to trace people who might have come in contact with the virus.

It operates through a state government smartphone application with all information encrypted and only available to health officials.

South Australia has also opened its borders to Victorian travellers for the first time since July, removing the need for them to isolate for 14 days.

That means SA is open to people from all states and territories as well as to those coming from New Zealand.

-AAP