Why VIC lockdown is likely to stay
The high number of coronavirus cases in Victoria over the past two weeks mean it's unlikely the state will be able to end its lockdown within six weeks, experts believe.
Victorians in Melbourne and the Mitchell Shire have already been in lockdown for two weeks, with another four to go, but the state is still recording more than 400 new coronavirus cases each day. Victoria recorded its worst day on Wednesday when 484 cases were identified.
Experts expected to see cases falling by now, although they say the figures are not as bad as they seem and the state did appear to be "flattening the curve".
However, the fact that cases aren't dropping yet could have ramifications for the state's lockdown.
Melbourne University epidemiologist Professor Tony Blakely told news.com.au that it depended on what the government wanted to achieve.
So far the Andrews Government has said it is seeking only to suppress the coronavirus rather than eliminate it.
But it has not given any indication of what suppression entails.
Reports in The Australian suggest the government is looking to get cases down to single digits and if this is accurate, Victorians may be facing a longer period under lockdown, some have suggested restrictions could extend to Christmas.
"If tight suppression is defined as 10 cases or less a day, then I think it's unlikely that the remaining four weeks of enhanced stage 3 restrictions will get us there," Prof Blakely said.
"It will probably take longer."
But if the government is happy to get cases down to a couple of hundred a day, then four weeks be enough, Prof Blakely said.
"It depends on what you want to do as a society, if you are willing to accept a couple of hundred cases a day until a vaccine is found, you don't need to do more than four weeks."
Professor Catherine Bennett, who is Chair in Epidemiology at Deakin University, agreed that four weeks might not be long enough to get cases in Victoria down to single-digits.
"Masks could speed up (the process) but you would want to be getting down to double digits within two weeks and this is a big ask," she said.
Even if authorities were successful in getting cases down to single digits by the end of four weeks, Prof Bennett said they may want to keep lockdown going for another two weeks to consolidate the success.
"You may still want to hold it there to make sure clusters have ended," she said.
"It will take two to four weeks to make sure the virus is suppressed within households.
"So we want to see numbers drop and then a couple of weeks of very low case numbers. It's not going to be less than four weeks clearly."
Both Prof Bennett and Prof Blakely have commended the Andrews Government for introducing new measures including a $300 payment for those getting tested and mandatory masks for those in lockdown areas.
Premier Daniel Andrews has also made strong remarks about the need for people to self-isolate while they wait for test results and the importance of getting tested as soon as symptoms appear.
Prof Blakely said it would likely take about 10 days for the impact of these measures to be known.
"If the numbers are the same in 10 days time … you would be scratching your head because they should have gone down," he said.
If numbers weren't coming down Prof Blakely said government should look at what essential industries could be causing the problem and perhaps closing them for a while.
He said the government already appeared to be looking closer at industry-specific arrangements such as the behaviour of cleaning crews going to aged care homes.
ELIMINATION, SUPPRESSION OR ACCEPTANCE
Prof Blakely said actions the state took depended greatly on what it was aiming for.
There are only three options: to suppress the virus, seek to eliminate it or accept herd immunity and allow it to spread within the community.
He said new advice to wear masks, as well as encouraging people to work from home if possible and maintain social distancing may eventually be enough to keep infections to less than 20 a day under a suppression strategy.
However, a suppression strategy was tricky because as soon as restrictions were relaxed, outbreaks of the virus would emerge.
"There's still a lot to learn if we are doing a suppression strategy," he said.
"I'm fairly confident there will still be outbreaks and soft lockdowns as we learn to live with the virus, which is why elimination is so attractive if you can achieve it."
Prof Blakely said an enhanced stage 2 lockdown may well be enough to keep the virus under control but it would be a case of trial and error.
"We haven't worked this out yet because suppression has clearly failed in Victoria," he said.
"What we had in place six weeks ago was not enough to contain the outbreak."
Prof Blakely said NSW had seemed to be more successful with its aggressive contact tracing and testing system and if so, Victoria should try to understand what it is doing differently.
"It could be purely just luck, or maybe it is better contact tracing, we don't know."
If Victoria did decide to aim for elimination, Prof Blakely said it should be moving to a stricter stage 4 lockdown straight away.
"What we do next should be contingent on what the goal is, and it's a societal decision."
However, Prof Blakely believes it's not worth bringing in a stage 4 lockdown unless the state wanted to eliminate the virus, or because its health system was being overrun with cases.
When asked about whether the six-week lockdown that runs until August 16 could be extended, the Premier told reporters on Thursday he didn't know yet.
"To be frank and direct I can't give you an answer about what things look like in three and a half or four weeks' time," he said.
"Certainly over the last two weeks we're not seeing that absolutely out of control growth to thousands of cases a day, there seems to be a relative stability.
"But that's not good enough, we have to drive the numbers down.
"Unless we all play our part, unless we all recognise that we all have a stake in this then the lockdown will be longer."
Originally published as Why VIC lockdown is likely to stay