What Australia needs to do to avoid a third Covid wave
As Victoria reaches the end of its second wave of the coronavirus, the focus is now on ensuring a third wave doesn’t hit as Australia heads into summer.
Guardian Australia spoke to leading epidemiologists about the lessons learned from other countries, particularly in Europe, that are experiencing a resurgence in cases.
What does Australia need to do to avoid a third wave?
Don’t open up too early
Israel was praised for its swift response to the first wave of the pandemic. But when it eased restrictions in May, the virus began to spread again.
“They eased restrictions very quickly and then they had a couple of big outbreaks in schools, high schools, one in Jerusalem and one in Tel Aviv, and then it spread like crazy,” says Prof Michael Toole, an epidemiologist from Melbourne’s Burnet Institute.
That could happen in Melbourne if restrictions are lifted too early, says Prof Marylouise McLaws, an infectious disease specialist from the University of New South Wales and advisor to the World Health Organisation.
“We’re only at risk [of a third wave] if the authorities in Victoria are pressured into lifting restrictions,” McLaws says. “They are still at a critical phase.”
Melbourne has been under stage four restrictions for eight weeks, and was under stay-at-home orders for three weeks before that. Premier Daniel Andrews has indicated he may bring forward some planned easing of restrictions on Sunday, in response to the daily case numbers falling more rapidly than anticipated.
The city is currently averaging just over 25 cases per day, and restrictions will not be significantly eased until that average drops to five or fewer.
McLaws says that the tipping point to overwhelm contact tracing and risk exponential cases is 100 cases in total in a fortnight. New South Wales reached that point on 21 July and has taken two months to return to an average of below five local cases per day, she says.
Prof Catherine Bennett, the chair of epidemiology at Deakin University, says that Victorian authorities ought to be able to cope with eased restrictions under the current caseload, because most new cases are connected to outbreaks.
“These are the cases persisting despite lockdown because they are in essential workers, they are in aged care, healthcare, police,” she says. “More stage four forever is not going to get rid of them, there’s got to be other ways to shut them down.”
Don’t lock down too late
The United Kingdom and most European countries are a lesson in moving too late.
Bars and restaurants will be closed in Paris from this weekend, after the city recorded a record 16,096 cases in one day. That’s too late to bring it under control, says McLaws.
“It’s interesting and instructive to compare us to Europe.
“It’s a lesson in what not to do … They have been pushed by economics rather than by health, where our leaders have been pushed by health protection first and foremost.”
Europe does not have the advantage of geographic isolation that Australia has, so the ability to get numbers to a very low level is limited. Still, McLaws says the UK’s decision to institute a traffic light system for overseas travel was “a fairly management-light perspective”. And the lack of testing in the UK, she adds, meant they did not have the data to catch outbreaks early.
“We do not want to become like Boris Johnson and throw our hands up and go, ‘well we might think about putting in a couple of hours curfew in the local pubs’,” she says. “We don’t want to become inert or quite frankly lazy in our approach to trying to look after our local residents.”
Make it a habit to wear a face mask
The best lesson for Australians to adopt from overseas is the habitual wearing of face masks. That may be one of the reasons that South Korea, Hong Kong, Taiwan, Vietnam and mainland China have been able to keep the virus under greater control than western nations, says McLaws.
Everyone in Australia should get used to wearing a face mask in the supermarket and on public transport until there is widespread vaccination, which McLaws says won’t be before the end of 2021. That should be the case even if the nation’s daily case numbers remain in single digits, she says, because of the unknown impact of asymptomatic spread.
“It also sends a really good visual reminder that we’re still in Covid,” she says. “Because without that reminder at a shopping mall, people don’t keep their distance because they keep forgetting that we’re still in a pandemic.”
Burnet’s Michael Toole says face masks should remain mandatory in Victoria until case numbers are effectively at zero, but requiring people in Perth and Darwin to wear them is “not practical”.
Bennett says a focus on prevention – face masks in enclosed public spaces, rigorous hand hygiene, remaining 1.5m apart in public – is the key to living with the coronavirus over the medium term.
Decentralised, ‘aggressive’ contact tracing
South Korea has ridden out the second wave better than any other democratic nation, says Toole. “They don’t go for big lockdowns,” he says. “They close bars, clubs, close churches again, but they have a really aggressive test and trace system and that’s been the key to the success.”
The South Korean contact tracing system is decentralised and works on mobilising local health units. New South Wales, which has the best contact tracing system in Australia, is the same.
Victoria moved to that model this month, after the system was overwhelmed in the second wave. Toole says the success of that change can be seen in the management of the Casey cluster. All three experts say they believe Victoria’s updated contact tracing system should be able to contain any new outbreaks.
“I think decentralised contact tracing is an important lesson,” Toole says. “Test and trace and isolate is the core tool we have to control this pandemic.”
McLaws says that as Australia’s domestic borders open up, there will also be a need for a national system, or greater participation between jurisdictions, to ensure contacts can be rapidly traced across borders.
Bennett says contact tracing must “go beyond that first ring of contacts” and “ask everyone to stay home, be monitored, get tested”. “If we can do that with only the sporadic cases we now have, then we’re in a much better position to never ever see the kind of expansion of cases that we’re seeing in Europe now,” she says.
Enforce rules, but make them evidence-based
Australians are used to strict public safety rules and have accepted both restrictions and hefty fines with less complaint than other nations. Toole says that voluntary rules don’t always work in public health, so a level of enforcement is necessary.
“We know that, from seatbelts and bicycle helmets and not smoking in restaurants, you do need a level of enforcement,” he says.
Without continued enforcement you could see what happened in Europe occur in Australia, especially as it heads into summer.
“When they did ease restrictions, people did go crazy and they didn’t obey the baseline social distancing measures,” Toole says. “They went to bars, went to beaches, went to clubs, and France recorded 13,000 cases in one day the other day.” (France had a record 16,096 cases on Thursday.)
Bennett warns that if those rules are not evidence-based, public support could wane. She also criticises the increasingly polarised political climate in Victoria, which has made nuanced debate of the evidence difficult.
The next big public health task should be analysing all of the more than 26,000 positive cases recorded to date in Australia to identify which specific measures, of the many restrictions imposed in lockdown, have had the greatest impact.
“We need to make sure everyone does trust our health systems and that our health systems are trustworthy,” she says. “With that, we must start to really unpack and evaluate exactly what has happened so that, should we have to face anything like this again, there’s less guesswork, less politics, and a lot more evidence.”
We do not want to become like Boris Johnson Prof Marylouise McLaws