Australia could be "on the cusp" of slowing the infections of coronavirus to the point that the epidemic "dies out", Australia's Deputy Chief Medical Officer says.

Professor Paul Kelly said the number of people infected by one person with COVID-19 was a key component in understanding how it spreads.

"Ideally where you want to be is below one, so less than one other person being infected after a person themselves had the infection," he said.

"And once you get to that point, the virus dies out, or the epidemic dies out. And so at the moment we're probably on the cusp of that in Australia.

"Now whether that's where we're going to be in several weeks or months time, remains to be seen."

Professor Kelly reinforced government warnings that people should stay home over the Easter long weekend.

"This is not time for us to be changing the rules in terms of social distancing and the other things we've done in society over recent weeks," he said.

"It's a time to consolidate those gains and to then of course to consider what might happen in the future. But at this time, the stay-at-home message is really important."

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NRL players and coaches not 'a law unto themselves'

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 53 seconds 53 s Professor Kelly warned the NRL against restarting its season early in the midst of the pandemic.

Professor Kelly also cast doubt over NRL's plans to re-start its season late next month, saying relaxing social distancing measures could speed up the spread of the virus.

"I don't think they're a law unto themselves. Some of the players and coaches might think so, but they're part of society and they have a part, as we have all done, to support not only safety for themselves but for all of us," he said.

"To be really frank about this, we all have a place in this and if we loosen the social distancing measures at the moment it can have implications down the track which are not foreseen."

The NRL said it would put strict testing measures in place along with other protocols to minimise the risk of infection.

But Professor Kelly said while players were generally young and fit, support staff could be at higher risk.

"(South Sydney coach) Wayne Bennett I think's in his 70s, so he would be in a more vulnerable group, Ricky Stuart here with the mighty (Canberra) Raiders, he would potentially be in a vulnerable group, although he's a bit younger. "So I think thinking about the team, not just the players but those that are the support around them is important."

He said while he encouraged all codes to start making their post-pandemic plans, he was not sure May would be the time to do it and that the NRL would need permission to go ahead with the season then.