After almost two months of uncertainty, fear and economic pain and loss, Australia has largely been able to keep the spread of coronavirus contained.
Nearly 90 per cent of coronavirus cases have since recovered, and now there are about 615 active cases across the country.
But with restrictions easing in states this week and recent outbreaks of the potentially deadly illness at the Cedar Meats plant in Victoria and Newmarch House aged care home in New South Wales, a whole new set of questions has cropped up.
With the help of an expert, we’ve got some answers.
What would a second wave look like?
A second wave of coronavirus infections won’t be determined solely on the number of cases.
The Department of Health said the most concerning situations were cases where the origin of the infection is unknown and cases where contact tracing is difficult or incomplete.
These situations make it much harder to control the spread of the virus, and will increase the possibility of a second wave.
A spokeswoman said “any second wave, and the timing of it, will depend on how well we continue to apply the restrictions and other control measures as outlined by the Federal Government and jurisdictions”.
This is why physical distancing, good hygiene, and effective contact tracing are so important.
“Tracing contacts quickly and effectively is of utmost importance,” the spokeswoman said.
“The faster and more effectively we find all suspected cases of COVID-19, test, isolate and treat the confirmed cases and trace their contacts, then the harder we make it for the virus to spread”.
Whether we’ll see a second wave is hard to predict
It’s certainly possible, and Chief Medical Officer Professor Brendan Murphy said it’s what worries him the most.
Chief Medical Officer Brendan Murphy worries about a second wave of infections.(ABC News: Ian Cutmore)
But whether we can predict a second wave has something to do with the reproduction number, the number used to reflect how infectious a disease is.
R0 is the basic reproductive number and equals the number of people a single case infects on average (assuming the whole population is susceptible and that no strategies are in place).
The R0 is estimated to be about 2.5 for COVID-19.
Effective control strategies will reduce this number so the effective reproductive number (Reff) is less than one.
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Reff is used when there is some immunity or some intervention measures are in place to control a disease or virus.
The Reff can also vary because communities in different areas could have different levels of immunity.
At the moment, Australia’s Reff is sitting at just above one.
At the height of its outbreak China was at about three, meaning every person with coronavirus was spreading it to three other people.
Bond University Professor of Evidence-Based Medicine Paul Glasziou says we’ll keep getting infections until a vaccine is introduced.
Australia is estimated to be currently detecting about 92 per cent of all symptomatic cases. But Bond University Professor of Evidence-Based Medicine and general practitioner researcher Paul Glasziou said there will always be asymptomatic cases.
“There is a hope if you put out those fires there’s a possibility of getting to zero new infections, but there could always be people who have minor symptoms and don’t realise they have coronavirus and go on to infect a large number of people,” Professor Glasziou said.
Your questions on coronavirus answered:Restaurants, weddings and sporting events are ‘danger points’
Professor Glasziou said new outbreaks recorded this week in South Korea and China were all helped by groups of people gathering in close quarters indoors.
So to avoid more mass infections, Australians will need to reconsider concerts, nightclubs, busy pubs and supermarkets, packed lecture theatres and anything else that attracted lots of people to a confined space.
There’ll be no more events like this until we get a vaccine.(AAP Image: Joel Carrett)
Professor Glasziou said it was unlikely restrictions on indoor events would be eased for a while.
“In China most of the outbreaks occurred with people clustered indoors in some sort of way,” he said.
“Restaurants, weddings, not the funeral itself but the wake afterwards, they’re the danger points. A big group of people indoors can catch it and then disperse, spreading it throughout the community.”
“When we ease up restrictions, we will need to see how much we still need to keep around certain activities. Sporting events, particularly indoor ones, are going to be a no-no and big crowds indoors. We’ll have to find safe way of doing that.”
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Professor Glasziou suggested halving crowd sizes or having everyone wear masks could be potential solutions.
“The major thing is we now have the testing, the isolating, the contact tracing and quarantines in place,” he said. “The big unknown is how many other layers of protection we need.”
A second wave could cost Australia dearly
A second wave of infections could see the extreme lockdown measures of mid-March returned. And no-one wants that, least of all workers and business owners who have been without an income for weeks now.
Australian Medical Association president Dr Tony Bartone said reimposing shutdown measures would be worse than a slow easing of restrictions.
“If restrictions are lifted too fast and a second wave occurs, infecting more Australians, the process of re-imposing isolation would be far worse for the health of the population and for the economy than a cautious relaxation of restrictions,” Dr Bartone said.
“People should not get their hopes up too high at this stage, because rushing to get things back to normal, without caution and safeguards, risks a huge setback for everyone,” he said.
“The rush to get the NRL competition back in play, for example, is a significant risk for players and those they will interact with.
“A later, more gradual resumption would be a safer and more sensible option.”
Could things get worse this winter?
Deputy Chief Medical Officer Michael Kidd said health experts don’t have enough evidence to prove that colder weather affects COVID-10 transmission rates.
But he admits physical distancing will be more difficult as the cold weather arrives.
“Clearly, as the weather gets colder people tend to crowd more, we may get more crowding on public transport, or inside in venues,” Dr Kidd said.
“The mechanisms put in place to maintain physical distancing, to reduce the number of people to four square metres in each venue [are] incredibly important in helping to prevent any seasonal increase with COVID-19 cases.”
He reminded people over 65 and the Aboriginal and Torres Strait Islander population they are eligible for a free flu vaccination.
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