The Department of Health and Human Services also has asked South Australians to cancel all non-essential travel to Victoria.

Travellers arriving in Melbourne by plane from metropolitan Adelaide will have to undergo a coronavirus test, even if they don't have any symptoms.

The testing applies to anyone arriving by plane who has been in metropolitan Adelaide, but does not apply to anyone arriving from regional SA, or via a connecting flight from another location.

As SA deals with its outbreak crisis, Victoria on Wednesday reached 19 days without any deaths or new cases.

There are three active cases and 17,354 people were tested in the previous 24 hours.

Victorian Health Minister Martin Foley said on Wednesday morning that the SA border status is being reviewed hourly.

"We have no plans to close our borders, but we are monitoring literally on an hourly basis the situation in SA," Mr Foley told Channel Nine.

"Of course, we reserve the right to take further measures if the advice changes."

A testing site will be set up in Nhill, near the SA border, and will start on Thursday.

"The SA government has asked us to assist when it comes to testing, particularly of interstate truck movements," Mr Foley said.

The minister also backed the Victorian contact tracing system, which came in for much criticism during the state's second wave.

"Our contact tracing system is now excellent," he said.

"It has been tested like no other system across the country, whether that be in the Shepparton outbreak, the northern suburbs outbreak, the Kilmore outbreak.

"We are sharing those learnings with all the other jurisdictions and we're seeing a lot of those learnings applied in SA now.

"I've got to say, the South Australians are doing a fantastic effort."

A screening process has been instituted for every SA arrival at Melbourne and Mildura airports.

Names and details of 122 passengers aboard two flights to Tullamarine on Monday were recorded and 81 of those tested, with more planes expected to land on Wednesday.

Victoria's Deputy Chief Health Officer Allen Cheng said travellers are being told to isolate until they get their results.

"Clearly we're getting some flashbacks to the situation in Victoria," he said.

But he also said it was reassuring that all of the cases in the SA outbreak are linked together so far.

The state's virus death toll stands at 819, with the national figure 907.

Australian Associated Press