Coronavirus: What do mild symptoms mean?

Symptoms will be mild for about 80 per cent of people who contract coronavirus, experts have said.

But what does mild mean when it comes to what will be the most widespread global pandemic in living memory?

For most people it won't be the asymptomatic reaction that we've been hearing about – carriers of the virus who do not feel sick at all.

And for most people it won't mean being on the cusp of being hospitalised.

But for 80 per cent of people who contract COVID-19, it will be somewhere between the two.

For most, the mild symptoms are the most common ones.

What are the coronavirus symptoms?

"Ninety per cent of people are developing an elevated temperature, 70 per cent are developing a dry cough," University of Sydney pandemic researcher Adam Kamradt-Scott told nine.com.au.

"If they start to develop more serious illness, it will be lethargy, muscle aches and pains, shortness of breath, headaches."

A case not considered mild would probably involve pneumonia, which could exacerbate existing medical conditions.

GP and University of Melbourne lecturer Chance Pistoll said for some people, coronavirus will feel like a regular cold.

"A runny nose, sore throat, headaches," Dr Pistoll said.

"That's what it will be for the vast majority of people, and that's unfortunately the reason why it's spread so much in the community."

For the majority of patients though, symptoms may stop at a fever and dry cough – possibly keeping them in bed or on the couch, but out of the intensive care unit.

Complicating Australia's health system response is varying numbers of how many people will have serious symptoms.

"In China, it's been around six percent of people that develop critical conditions, but it's not clear if all six percent required intensive care," Dr Kamradt-Scott said.

"By contrast, Italy have stated that between nine and 11 percent have required admission to intensive care."

Coronavirus cases with no symptoms

There are a small number of coronavirus carriers who report no symptoms at all.

But determining how many is not currently possible.

"Unless you were to do surveillance of the entire population, you wouldn't be able to get a sense of how many people are asymptomatic," Dr Kamradt-Scott said.

"We need to focus on getting our health system ready to care for the most critically ill."

Self-isolation and social distancing is so important because the health system cannot spend time testing the well when it is expecting so many people to get seriously ill.

And with flu season bearing down on Australia, it will soon be a case of protecting the vulnerable from not one, but two serious illnesses.

"At some point, if we see widespread transmission, the decision will be taken to not test people for COVID-19," Dr Kamradt-Scott said.

"The most important thing is if you are feeling symptoms, you self-isolate.

"If you've got a whole lot of people developing a flu-like illness, then the focus at some point will have to shift from stopping testing to treatment."

The danger in mild coronavirus symptoms

The reason why COVID-19 spreads so effectively is because for so many, the symptoms are mild, said Dr Pistoll.

"They'll go out to the movies and go to a social gathering," he said.

"The data shows that each person who has COVID-19 will pass it on to four or five people."

And with the testing criteria so stringent, many people may not ever know if they have had it or not.

"There is a possibility that a lot of people will get it who won't know that they've had it," Dr Pistoll said.

"That's why it is so important that people who become a little bit unwell, that they isolate."

Will Australia end up like Italy?

Italy is currently suffering the worst fallout from the spread of coronavirus.

In spite of quarantine rules, cases of coronavirus are spiking in Italy, and hospitals there are overwhelmed.

But Australia is unlikely to have an outbreak as bad, Dr Kamradt-Scott said.

"Italy has 62 million living in 300,000 square kilometres," he said.

"Australia has 25 million in 7.7 million square kilometres.

"There are other factors, in Italy is much more culturally acceptable to smoke, and we know that smokers have higher morbidity."

Our low population density even in our big cities will slow the spread of the virus.

Read more: Live updates on the coronavirus pandemic

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