Australians have been told to start practising "social distancing" and stop shaking people's hands, in response to the coronavirus outbreak.

But chief medical officer Brendan Murphy said it's still okay to go to the gym and ride on public transport … for now.

So what should Australians be doing in the midst of this global pandemic?

Professor Murphy wants everyone to be practising "good hygiene", which means washing your hands regularly.

This morning, he indicated it was OK to shake other people's hands but this afternoon the Prime Minister, Scott Morrison, updated that advice, telling Australians "no more handshakes".

"That is a new thing we've moved to, something I will be practising," Mr Morrison said.

While non-essential gatherings of more than 500 people are being cancelled, Australians are being advised it's OK to go to the movies and ride on trains, ferries and buses.

People can also continue going to the gym, as long as they wash their hands and use hand sanitizer.

Stocking up on "a few days'" worth of groceries would also be sensible, according to Professor Murphy.

"We don't want to encourage major panic buying at the moment — we've seen that with the supermarket chains," he said.

"But I think it is probably sensible to have a few days of supply."

What will happen as the virus spreads?

The Health Minister, Greg Hunt, this morning expected the coronavirus outbreak to last for at least six months. He said "all options are on the table", including curbing travel and locking down parts of the country.

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When it comes to schools, it's a bit more complex. The states can close schools if necessary, but they do not want to move too early.

"The schools question will be very much guided by the medical advice," Mr Hunt said.

The Minister insisted Australia was "ahead of the curve" and was putting in place controls "dramatically earlier" than other countries.

Who should be taking extra precautions?

All travellers coming from overseas are now required to self-isolate for 14 days or face possible fines.

Mr Morrison said the new measure will come into effect at midnight AEDT on Sunday and will help slow the spread of the virus.

The virus poses the greatest risk to people over the age of 70 and those with existing health conditions.

According to Professor Murphy, that cohort should avoid doing anything that is not essential.

"If you're over 70 and you've got chronic disease, at the moment your risk is very low but you may want to think about more social distancing in the future," he said.

What should you do if you come into contact with a person with the virus?

Professor Murphy said international evidence suggested a person with coronavirus was most contagious when they start showing symptoms.

So anyone who has been in "close contact" with a person showing symptoms — or in the 24 hours before they became symptomatic — is at risk of contracting the virus.

Who is advising the Government?

The nation's chief medical officers and other health experts have been meeting for several hours every day to track the number of coronavirus cases and provide advice to the Commonwealth.

According to Mr Hunt, this committee, the Australian Health Protection Principal Committee, is the "paramount source of medical advice to the nation".

Separately, a "war-time" national cabinet has been set up, bringing together the Prime Minister and all state and territory leaders to respond to the crisis.

"Everything is up for consideration," Professor Murphy said.

"The premiers and the Prime Minister said to us, the health advisers, 'Give us your fearless advice and we will take it.'"