This was published 3 years ago
Elimination of COVID-19 possible in Victoria if lockdown endures
By Tom Cowie
The complete elimination of COVID-19 in Victoria is still a possibility, but one that would require the maintenance – and perhaps upgrading – of the state's strict social-distancing restrictions.
Epidemiologists told The Age that maintaining the state's restrictions and border lockdowns could lead to the virus being eliminated, rather than suppressed. Their comments come as other states begin to loosen their lockdown regimes after positive signs of flattening the curve of infection.
Premier Daniel Andrews and Chief Health Officer Brett Sutton have continued to maintain the need for one of the country's strictest lockdowns. They have stuck to May 11 as the date when stage three restrictions could be reviewed and downgraded.
Victoria recorded its sharpest increase in new cases in two weeks on Sunday as the total rose by 13 to 1384. Health Minister Jenny Mikakos attributed the rise in part to the biggest day of testing by any state. The state is attempting to test 100,000 people before May 11.
'I'm going to exaggerate a little bit but you can pretty much have the MCG open for say, 20,000 people.'Credit: Getty Images
"This two weeks will really tell us what's going on," said Professor Catherine Bennett, chair of epidemiology at Deakin University.
"If the testing blitz doesn't find any more cases [of community transmission] then I think it goes on the table as something people might want to consider in Victoria. But the risk is that we are isolated from the rest of the country."
Elimination is generally considered to be at least two weeks without an infection that can't be traced to a known source. A daily increase in cases wouldn't necessarily mean resetting the clock if they can be linked to somewhere such as a cluster from an aged care facility or factory.
Victoria appears tantalisingly close to having elimination as an option. In the past seven days, while overall cases have risen by 35, those with an unknown source of infection have grown by just five. There are 15 still under investigation.
In a report released last week, more than 100 researchers from the Group of Eight universities said choosing the elimination strategy over suppression would mean staying in lockdown for longer, possibly another 30 days.
Health Minister Jenny Mikakos.Credit: AAP
"There's no magic recipe but if you were going to go full hog for it, you know really go hard, then you would maintain the level of physical distancing and social policies we have at the moment," said epidemiologist Tony Blakeley.
High levels of testing would also be needed, experts say, as well as strict contact tracing of new cases. Closed borders may also be required, with New South Wales experiencing higher levels of community transmission.
Proposing all of this to a population already fatigued by lockdowns would be politically difficult, but the benefits of such a strategy could be greater.
"I'm going to exaggerate a little bit but you can pretty much have the MCG open for, say, 20,000 people or something like that," said Professor Blakeley of the elimination scenario.
"Because you've really got no transmission, as long as you've got your borders closed, you can get on and function near normally."
Sticking with suppression by opening up society slightly could lead to a "limbo" period of waiting for a vaccine that might never arrive, he said.
But while elimination would boost confidence in the community that people could move about more safely, things could change quickly.
"Common sense plus experience in places like Singapore tells you as long as you've got a single case you can get another outbreak on top of you before you know about it," said University of Melbourne epidemiologist Professor John Mathews.
Last week, New Zealand claimed it had achieved elimination, allowing its people to come out of a lockdown that has been harsher than the one in Australia. However, some think the country may have jumped the gun.
"You really have to wait for a couple of weeks before you declare it because of the incubation period, and you have about half of the people who are asymptomatic," said Professor Blakeley.
When asked recently if Victoria could look at elimination as a strategy, Mr Andrews said the agreed national strategy was suppression. However, he left the door open to going further.
"Ultimately if you are very successful in suppressing the virus, though, then more than that becomes within reach," he said.