Crisp temperatures this weekend are the first sign beach weather is well and truly on its way out.
The changing of seasons has fuelled speculation across the world about how the weather will impact the spread of COVID-19, and whether the pandemic will get worse in Australia where winter is on its way.
And while experts say it would be a “miracle” if we escaped future coronavirus spikes, they say the weather has little to do with it.
Is there a link between weather and COVID-19?
There have been some claims the virus spreads faster in winter and slower in summer.
But COVID-19 hasn’t been around for long enough for researchers to draw definitive conclusions about whether temperature impacts the virus.
Experts told the ABC talk of a direct link between the weather and the spread of the virus was dubious.
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Professor Michael Wallach, an expert in infectious diseases from the University of Technology Sydney, says the virus “doesn’t seem to care about the weather”.
“I don’t think it’s simply a matter of warm or cold weather. This virus is extraordinarily good at transmitting and infecting human cells,” he said.
“For previous pandemics, the weather apparently did not have much of an effect.
“Pandemics generally are weather insensitive.”
Infectious diseases epidemiologist Meru Sheel from the Australian National University seconds that.
“It’s a new disease, so we don’t know whether there’s a direct link between the weather and COVID-19,” Dr Sheel said.
“Although, the evidence would suggest probably not.”
Coronavirus update: Follow the latest news in our daily wrap. Many states are experiencing cooler temperatures this weekend.(Supplied: Barclay White)Where did the connection come from?
China was entering winter when coronavirus first emerged.
“It’s likely a myth and people think [that] because the virus started spreading in winter, when in China and Europe it was winter,” Dr Sheel says.
Even US President Donald Trump was holding out hope COVID-19 would “miraculously” disappear in spring.
“You know, a lot of people think that it goes away in April, with heat, as the heat comes in. Typically that will go away in April,” he said in February.
But such claims ignore the fact the virus has been spreading in warmer countries, too — including Australia, Singapore and Indonesia.
“We saw in Australia in relatively warm weather [during] the peak in activity occurring,” Professor Wallach said.
“We see also what’s happening in Sweden, where they’re coming into spring now and people are outside — the transmission rate is high … we’re seeing a high level of mortality.”
Winter is on its way in Australia, but our coronavirus cases spiked when the weather was warmer.(Pexels: Burst)
Kathryn Snow, an epidemiologist from the University of Melbourne, says even though Australia’s transmission rate has been lower than countries that first experienced COVID-19 in winter, that was likely due to other factors.
“Some people have suggested that we were more successful in controlling the first wave of COVID-19 because it hit us at the end of our summer, while the northern countries were at the end of their winter,” Dr Snow said.
“I’m not sure about that. I think our success is down to the fact that we have a good health system and our governments acted very early, before COVID-19 had even reached us.”
Stay up-to-date on the coronavirus outbreakFlu does spread in winter — but not for reasons you might think
Influenza is called a “seasonal flu”.
“It’s seasonal because of the fact that when the weather gets cold, people are indoors, close the windows — and that increases its transmission,” Professor Wallach said.
So, instead of being outside in open air, in winter you’re going to prefer warmer indoor spaces — but so do other people, and that increases your risk of coming in contact with someone who has a flu or COVID-19.
“Winters add an extra layer of complexity because of the general increase in respiratory infections because of people being more in confined spaces,” Dr Sheel said.
“You tend to see more circulation of infections like influenza and RSV [respiratory syncytial virus] in winter, which can be challenging because then these infections can be a risk factor for COVID-19.”
Because our attention has been centred on COVID-19, people may have become complacent about the flu — which can also be deadly.
Because COVID-19 has symptoms similar to flu, people can brush it off as ‘just a cold’.(ABC News: Chris Gillette)
“We have to remind ourselves that flu is also a very dangerous virus, and the two together even more dangerous,” Professor Wallach said.
And because COVID-19 has symptoms similar to flu, people can brush it off as “just a cold”.
“We believe that there are many people who go through COVID-19 without knowing it, mixing it up with other things,” Professor Wallach said.
This is why experts have been calling on people to go get that flu shot.
“We should all be getting our flu shots this year as well, to take some pressure of the health system,” Dr Snow said.
What you need to know about coronavirus:So will we see a second wave of coronavirus? In some states, people can go to the beach again.(ABC News: Jesse Dorsett)
This weekend marks the easing of restrictions for people in many parts of the country.
If you’re in Western Australia, you can gather in a group of 50 people.
In Queensland, members of the same household can have a picnic in the park.
But this is not the time to lower your guard, experts warn.
“We should remain vigilant, no matter what the conditions look like outside [as] people are starting to go back to beaches and congregating again,” Professor Wallach said.
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He says we’re all dependent on each other’s good behaviour, because most people haven’t had COVID-19 yet.
“Because we did so well in locking down, a very small proportion of the population have been infected,” he said.
“So, the minute we start congregating, and there’s a single seed — a single person — we start the whole thing going again. And we’re back to where we were.”
But even with all the precautions taken, Professor Wallach says we have to be prepared that “not nice things might happen again in the future.”
“I could almost say with some level of certainty, we’re going to face future spikes. To me it would be a miracle if we didn’t,” he said.
Professor Wallach says it’s hard to predict when the second wave might hit us, but some researchers expect in September or October — just as the northern hemisphere is approaching winter.
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