An infectious diseases expert believes Australia is already into its second wave of coronavirus.
Professor Peter Collignon, who is from The Australian National University Medical School, tweeted on Sunday “Australia (population 26 million) is getting a second wave of Covid”.
“More of a concern than the first wave as most cases are community transmission and nearly all from just one city (Melbourne),” Professor Collignon tweeted.
He also predicted the likelihood of spreading the infectious disease could increase due to the time of year.
“Winter has just started here, so also likely a factor in increasing risk of spread,” he said.
Victoria’s areas of Metro Melbourne and Mitchell Shire are currently in lockdown with residents only allowed to leave their houses for exercise, to provide care, for work or to buy essential items.
On Sunday, the state’s premier Daniel Andrews said another 273 cases had been reported.
Adrian Esterman, professor of biostatistics at the University of South Australia, wrote in a piece for The Conversation that Victoria is “undeniably” in a second wave.
Professor Esterman said it’s hard to know where to go from here.
“Daily cases could still rapidly increase, or we could have reached the peak and we might start seeing cases subside,” he said.
“However, the number of new cases each day isn’t necessarily the critical factor. More important is the daily number of new community-acquired infections.
“Because we have no idea where these people got infected, it makes controlling the situation very difficult.”
Some people questioned Professor Collignon’s assessment of a second wave.
But what constitutes one?
Dr Mike Tildesley, from the University of Warwick in England, told the BBC “how you define a wave is arbitrary” and added it’s not really scientific.
However, it could be considered like waves in the ocean – a large one comes in and crashes down before a second follows.
Australia (pop 26m) is getting a 2nd wave of Covid. More of a concern than the first wave as most cases are community transmission and nearly all from just one city (Melbourne). Winter has just started here, so also likely a factor in increasing risk of spread. pic.twitter.com/shRKuRyzZM— Peter Collignon (@CollignonPeter) July 12, 2020
In the case of coronavirus – we see a large number of cases, then a low number, before an increase in cases again.
That second lot of increased cases could be considered the second wave.
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