Victoria must reduce its coronavirus community transmission to virtually zero before Western Australia reopens its borders, the state's chief health officer says.
Plans to reopen WA's interstate borders on 8 August have been shelved amid a fresh outbreak of cases in several Melbourne hotspots.
There are now 288 active cases in Victoria, with 271 believed to have come from community transmission.
WA Chief Health Officer Andy Robertson on Monday said he wouldn't be advising the state government to reopen borders until Victoria's numbers significantly improved.
"If we look at Queensland, they haven't had any cases now for three or four weeks. NSW has had some, but they've got low levels," Dr Robertson told ABC radio.
"If either they've got no community spread or we're fairly confident that what little community spread (exists) is well under control and being effectively managed, that would be the time we would provide that advice (to reopen)."
WA recorded no new cases on Monday. The state has just four active cases, all in hotel quarantine and linked to overseas travel.
WA's Chief Health Officer Andy Robertson. Source: DEPARTMENT OF HEALTH
But with most restrictions on gatherings now lifted, Dr Robertson urged West Australians to maintain good hygiene practices.
"We have to realise that it can come back," he said.
"We are obviously protected to a degree by our borders ... (but) there's certainly quite a bit of traffic now on aircraft coming across from interstate."
He said COVID-19 could be reintroduced into WA and then, "given that we are reasonably open now, we could expect further outbreaks".
All people in hotel quarantine in WA are tested on day 12 of their 14-day quarantine period.
Dr Robertson said while authorities had the power to compel people in quarantine to be tested, they hadn't needed to use it.
"People have generally been very compliant," he said.
This comes as Victoria imposes mandatory testing on returned overseas travellers in hotel quarantine after it was revealed about 30 per cent were refusing to be tested.
The Australian Medical Association's Dr Chris Moy said on Monday there are genuine concerns around the outbreak in Victoria, which could be enough for other states such as Queensland to also keep its borders closed.
Queensland Premier Annastacia Palaszczuk will announce on Tuesday when the next easing of restrictions will be triggered and possibly when the borders, which have been closed since March, will reopen.
The state has just two active cases and recorded just one positive test in the past week.
"There would definitely be good reasons to wait a week or two to decide what is happening," Dr Moy told AAP.
Even though the Victorian government has increased its testing regime for those in quarantine and its health protocols, any benefits may not flow through until mid July, says Dr Moy.
His biggest concern is the number of community transmissions that are being detected in Victoria.
"People may argue (the increase in positive tests) is because they are doing more testing, but they're finding cases and that's the concern," he said
"The virus is there, it's hiding under the hood."
But Prime Minister Scott Morrison said there was no reason why Queensland shouldn't open its borders and hoped the date would not be pushed back.
“I would hope it will confirm the 10 July 10 date. [Ms Palaszczuk] didn’t offer any more on that on Friday [at National Cabinet],” he said.
“I was please to see that both South Australia and Tasmania confirmed their openings.
“I see no reason we can’t go ahead with these openings, they should go ahead.
“It’s costing jobs in those states and I’m please those states have pressed ahead. I would hope that Annastacia Palaszczuk will do the same thing in Queensland.”
People in Australia must stay at least 1.5 metres away from others. Check your state’s restrictions on gathering limits. Testing for coronavirus is now widely available across Australia. If you are experiencing cold or flu symptoms, arrange a test by calling your doctor or contact the Coronavirus Health Information Hotline on 1800 020 080.
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