Heavy police presence at South Australia-Victoria border as it closes

Victoria's border to South Australia has closed overnight as the state aims to protect its zero case streak.

The hard border is in place for 48 hours, before a permit system comes into effect from 11.59pm on Saturday.

There is a large police presence at the border this morning as police check every car and truck attempting to cross between the two states after the new rule came into force from midnight.

Truck drivers - who are exempt from the border ban - can have their temperatures taken at Nil, around 45 kilometres from the border and have a COVID-19 test if they chose.

Results will be fast tracked and truckies will not need to self-isolate upon entry.

"Our position should be jealously guarded," Premier Daniel Andrews said yesterday.

Under the hard border, only freight drivers and those with medical or emergency reasons, urgent animal welfare or as authorised by law will be allowed into Victoria.

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The closure comes as South Australia recorded no new COVID-19 cases yesterday, the first day of its strict six-day "circuit breaker" lockdown.

"There is no way that we can have people who will not be leaving their home in SA doing so and travelling to our state - not at this time," Mr Andrews said.

"These arrangements will not be in place a moment longer than they need to be."

The details of the permit scheme are yet to be provided, but the reasons to enter Victoria will include:

• If you are an emergency services worker or a worker providing essential services
• For agricultural work
• To receive medical care (including seeking coronavirus testing), obtain medical supplies or compassionate reasons
• To shop to obtain essential supplies

Victoria Police have established check points on key roads on the Victoria-South Australia border, the state government likening it to the "ring of steel" between Melbourne and regional Victoria.

The premier said the latest measures were taken as an "abundance of caution" due to the recent climbing coronavirus cases in South Australia.

While freight will continue through the hard border closure, Mr Andrews said all truck drivers entering Victoria from South Australia would be tested.

"Truck drivers will be tested, all of them coming from South Australia … we believe that is an appropriate response," he said.

Victoria's Deputy Chief Health Officer Dr Allen Cheng said there were "concerning developments" in South Australia that led to the government closing the border.

South Australia reported a case in a medi-hotel that resulted from a "very transient" contact at a pizza restaurant, Dr Cheng said.

"The source case had worked there while infectious for 10 days so potentially a large number of contacts," he said.

He said the hard lockdown in South Australia reflected their concern that hidden transmission may be occurring, which made it necessary to close the border.

Mr Andrews said border restrictions would hopefully lift at the same time as South Australia's lockdown.

"Hopefully these low numbers continue to be a feature of their public health response and when they lift their rules, when they change the restrictions that they have put in place, we will be able to make changes to these border controls," he said.

The hard border comes after fragments of COVID-19 had been detected in Benalla in the state's north-east and Portland in the state's south-west - about 80 kilometres from the South Australia border.

Dr Cheng said the viral fragments could be from an active case or a recovered case who may be shedding the virus.

READ MORE: PM 'reasonably confident' SA can emerge from lockdown in six days

"It's always difficult to interpret ... it is possible that a recovered case from Melbourne has visited these areas," he said.

Anyone who visited those areas between November 15 and 17 and showing any symptoms, however minor is urged to get tested.