Covid 19 coronavirus: NSW positive case visits multiple sites in Victoria and South Australia

Victoria slammed shut the border between NSW and the state at midnight. Photo / News Corp

A NSW furniture removalist who visited households in Victoria and South Australia has tested positive to Covid-19.

Victorian Health Minister Martin Foley confirmed on Monday that the man, who tested positive for the virus late on Sunday evening, was in the states while infectious.

Foley said he expected there to be "multiple exposure sites" as authorities investigate.

"We will be looking to fill the gaps as soon as possible, but we expect there would be exposure sites and expect there would be people required to quarantine," Foley said.

"Our very proximity to NSW and their current predicament makes this risk of incursion very real."

Victoria slammed shut the border between NSW and the state at midnight. Photo / News Corp

The removalist visited households in Victoria and SA, staying overnight in Victoria on July 8 before driving into South Australia on July 9 and returning to NSW and taking a test on July 10.

He tested positive on July 11.

It comes as Victoria recorded its 12th consecutive day without a locally acquired Covid-19 case and as NSW battles to restrain its aggressive outbreak of the highly infectious Delta strain.

Victoria declared all of NSW a red zone and closed the border between the states at midnight, as cases in the state continued to skyrocket.

Victorian residents are able to return to the state but must get tested and quarantine for 14 days if entering from a red zone.

Border communities have been plunged into a "border bubble" arrangement for the third time in 13 months.

Foley said the decision was made due to the incredibly worrying situation in NSW, which recorded 112 cases overnight.

He said it could potentially be the "third incursion" in the state as a result of the NSW outbreak, which included the Sandringham and Virgin airline cases.

"We know that this Delta virus moves incredibly fast and is highly infectious, so once we get that information from NSW we will be sharing that with the community," he said.

"These are precisely the reasons that our public health team have set tougher border restrictions.

"Given the deteriorating position in NSW, Victoria needed to take the steps to seriously limit the movement of people and limit the risk of incursions into Victoria."