As Australia’s lockdown restrictions begin to relax, there is a new phrase everyone is talking about: the second wave.

With the nation now consistently recording less than 20 new coronavirus cases per day over the past week, lifting the nationwide social distancing restrictions will be discussed a week earlier than expected, the Prime Minister announced in his latest press conference.

But as Western Australia premier Mark McGowan said on the weekend, in a sentiment echoed by medical experts and politicians across the nation, “Having our numbers stay low is incredibly important to us being able to free up some of the restrictions.”

“We just want to be sure. The history of pandemics around the world is there is a second wave.”

Chief medical officer Professor Brendan Murphy also confirmed on Sunday that it will be a slow path back to normality, with experts wary of the risk posed by a fresh onset of infections.

“Although we are now seriously looking at what measures could be relaxed… we are very cautious about the need to move slowly,” Professor Murphy told reporters in Canberra.

“The lessons we have learnt from overseas is that if you go too quickly and open up things too quickly, you can get a second wave.”

Listen: Life after 40 days of lockdown: checking in with Italy, England and Spain. Post continues below. 

So… what exactly is a second wave?

As infectious disease experts James Wood and Nic Geard wrote for The Conversation, “When an outbreak is brought under control by social distancing and other measures, it’s possible only a small proportion of the population will have been infected and gained immunity.

“If a population has not achieved herd immunity, enough susceptible people may remain to fuel a second wave if controls are relaxed and infection is reintroduced.”

Whist the extreme social distancing measures may not be maintainable in the long-term, lifting them too quickly could be disastrous with COVID-19 still in the community.

This is why the Australian Health Protection Principal Committee (AHPPC) has 15 requirements that must be satisfied before the easing of coronavirus restrictions. It will ensure there are strict measures in place to mitigate the risk of a second wave.

If a second wave does occur, experts say it could be just as dangerous, if not worse.

For example, if we look at the 1918 Spanish flu, there were three waves of the illness during the pandemic. The first wave in the spring wasn’t that bad – it was the second wave in autumn that was the deadliest because it had mutated into a much deadlier version of its former self.

What happened in Singapore?

A second wave of coronavirus is what occurred in Singapore.

In February, the Director-General of the World Health Organisation, Dr Tedros Adhanom Ghebreyesus, publicly praised Singapore’s “no stone unturned” approach to minimising the spread of COVID-19.

The Asian city-state had moved faster than most and as other countries locked down around it, Singapore managed to remain relatively open. Until April 7, when the country’s 5.7 million residents entered a partial lockdown after experiencing an alarming spike in new cases. It seemed likely that residents forced to return home due to regulations overseas may have brought the virus with them, allowing a second wave of infections to slip through the net.

Watch: Singapore’s migrant worker dorms suffer COVID-19 outbreak. Post continues below. 

Singapore now has among the highest number of infections in Asia, mainly due to outbreaks in cramped migrant-worker dormitories.

On Saturday, 447 new coronavirus infections were confirmed in Singapore, the smallest daily rise in two weeks, taking the total to 17,548 with 16 virus-related deaths. Most of the new cases were among migrant workers, the health ministry said. It has managed to curb the spread of the disease among locals outside the dormitories.

They are also now facing the deepest recession in its 55-year history.

Labor’s Andrew Giles spoke of the possibility of a second wave on Saturday, telling ABC television: “I think everyone has really taken very seriously the experience of Singapore, which was, of course, lauded as a great example of how to manage the pandemic, and of course they have been struck by a very significant second wave.”

“And I think this is something that I am sure is on the minds of all the chief medical officers and everyone who sits around the national cabinet table.”

For more on COVID-19:

• Australia has met 11 out of 15 requirements to ease restrictions. These are the four left.
• “I broke off my engagement”: 9 women share how isolation has changed their relationships.
• The 5 habits that will be the hardest to break after lockdown is finally lifted.

To protect yourself and the community from COVID-19, remain in your home unless strictly necessary, keep at least 1.5 metres away from other people, regularly wash your hands and avoid touching your face.

If you are sick and believe you have symptoms of COVID-19, call your GP ahead of time to book an appointment. Or call the national Coronavirus Health Information Line for advice on 1800 020 080. If you are experiencing a medical emergency, call 000.

To keep up to date with the latest information, please visit the Department of Health website.

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