Victoria has recorded its 19th-straight day of no new coronavirus cases and no deaths.

The state still has three active cases, a number that has not changed in a week.

Premier Daniel Andrews is poised to announce a further relaxation of virus rules for the state on Sunday.

However, there are growing concerns about the the Parafield outbreak in Adelaide’s northern suburbs.

It had grown to 20 cases on Tuesday, with more than 6000 tests conducted in South Australia early this week. Premier Steven Marshall has reportedly told Adelaide radio that more cases will be added to the cluster on Wednesday.

Victoria has already urged South Australians to avoid crossing its border unless its absolutely essential.

Victoria has not closed its border to SA but Health Minister Martin Foley said on Wednesday truck drivers would be screened for COVID at border checkpoints.

Arrivals into Melbourne Airport from South Australia are also subject to interviews and temperature checks.