The virus hotspots which could be heading for a new lockdown

Six virus hotspots in Melbourne could be locked down as the state battles to stop community transmissions which continue to increase.

Victoria's active coronavirus cases have more than doubled in a week.

State health officials confirmed 17 new cases on Tuesday morning, 16 of which appear to have come from community transmission.

Federal Health Minister Greg Hunt confirmed to ABC News Breakfast reports published by The Age that the suburbs of Brimbank, Cardinia, Casey, Darebin, Hume and Moreland are facing localised lockdowns if their virus cases aren’t contained by July 19.

Mr Hunt said he agreed with the approach.

“Nationally, we’ve established testing, tracing and local response. That includes the potential for travel warnings in and out of the local government area, or going further as we did in northwest Tasmania,” he said.

“So we effectively implemented this same approach where there was a significant outbreak around Burnie. It was very difficult for the local population, but ultimately, it led to the control of what was a far greater outbreak in terms of cases to population number. And Tasmania has been doing extraordinarily well since.

“Victoria has significantly greater resources. I think they've set the right structure in place, and we'll continue to support. And that remains an option. But I am hopeful that with this level of testing…that we will be able to control and suppress those cases.

Borders closed to keep Australia an ‘island sanctuary’

Mr Hunt told ABC radio on Tuesday Australia's borders will remain closed for "a very significant" amount of time.

Mr Hunt says infection rates are accelerating around the world.

"For the time being we are an island sanctuary," he said.

The number of global coronavirus infections has exceeded nine million.

Mr Hunt appeared to suggest international borders would be shut until a vaccine was found.

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Victorian scenario ‘should not force hand of other states’

There's a "lot of luck" involved in the caseload when comparing Victoria and NSW, Chief Medical Officer Brendan Murphy said.

He said NSW had been better at bringing community transmission under control by using measures such as pop-up clinics in hotspots.

But he said he did not see any reason why Victoria's cases should force other states to change their plans.

South Australia sent a team of experts to Victoria on Tuesday to help with contact tracing. They will spend three weeks helping health officials.

Vaccine trial results imminent

Meanwhile, the first results from the clinical trials of several different candidate vaccines should be known by late July.

Professor Murphy said the government was examining Australia's capacity to manufacture vaccines if a working one is found.

Volunteers are being recruited for a possible COVID-19 vaccine trial in Adelaide.

Researchers at the Royal Adelaide Hospital are looking for about 100 healthy adults for the trial which may be conducted later this year.

with AAP

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