From the security of his office in Canberra, the nation's top doctor fielded questions from politicians across the ditch on Australia's response to COVID-19.

Key points: Nightclubs and music festivals to remain closed for foreseeable future

Nightclubs and music festivals to remain closed for foreseeable future Industries like construction could close if virus rates worsen

Industries like construction could close if virus rates worsen Australia and New Zealand's "hard and fast" approach to virus is working

Brendan Murphy claimed an "illegal dinner party" attended by medics in Tasmania may have caused the latest coronavirus cluster. He later withdrew the remark.

Here's what else we learned.

The human race will change for good

By closing the borders, quarantining travellers and clamping down on group gatherings, Australia has so far managed to "flatten the curve" and limit community transmission.

So, many people are daring to dream of a post COVID-19 world where life can return to normal.

But Professor Murphy said, in some ways, this crisis will change human behaviour for good.

"We'll all be doing better hand hygiene from now on," he said.

"There are some things we'll do differently, always."

Professor Murphy and other health experts have said fewer cases of colds and flus had been reported in Australia because people were keeping their distance from other people and practicing better hygiene.

Brendan Murphy says he does not see music festivals being allowed anytime soon. ( ABC Central Victoria: Corey Hague )

The day the music festival (kind of) died

For ravers and music lovers, the news is not so good.

While the Prime Minister has consistently said the coronavirus restrictions would remain in place for six months, behind the scenes National Cabinet is beginning to chart a path out of the crisis.

That includes what a gradual easing of restrictions might look like.

Professor Murphy said until a vaccine or treatment was found, he does not believe the social distancing measures can be relaxed entirely.

"Unless you're absolutely, completely confident about your borders, your testing, your surveillance, you can't relax a measure of distancing," he said.

"It's hard for me to envisage reopening of nightclubs and big music festivals in the foreseeable future."

Construction, manufacturing to close if things get worse

Australia has banned indoor and outdoor gatherings, closed pubs, clubs, cinemas, gyms and casinos and limited cafes and restaurants to takeaway service only.

In New Zealand, which shut down all commercial activity, its politicians probed Professor Murphy about why Australia had not gone harder.

Any measures had to be sustainable for the long haul, he said, so the advice was to close businesses that were not "absolutely essential to the economy".

"Clearly if things get worse we will go harder," he said.

"[In that case] we would be keen to close construction, manufacturing and retail more broadly."

Elimination versus suppression

Much has been made of New Zealand's "elimination" strategy compared to Australia's "suppression and control" approach.

But Professor Murphy said the aim was not that different.

"Our goals are very much the same; to get transmission down to as low as possible," he said.

"And if we get rid of it, that would be great."

Professor Murphy said Australia would "love" to eliminate the virus entirely but likened it to a "nirvana" that could not necessarily be achieved.

But he said both Australia and New Zealand were in a strong position because they had gone "hard and fast" in their response to the virus.

"If you go hard late, as the UK has done, you see what carnage you suffer on the way through," he said.

"It's very, very hard to bring a large outbreak under control."

The United Kingdom has recorded more than 88,000 cases and 11,300 deaths.

Conversely, in New Zealand, a country of five million people, the death toll has not yet topped 10.

As of Tuesday morning, Australia had 6,366 confirmed cases and 61 deaths.