Chief Medical Officer Brendan Murphy has defended the early modelling of expected coronavirus cases in Australia, despite the numbers being nowhere near as bad as even the best-case scenario.
Authorities have never released full modelling but in early April released some data.
Prepared by the Doherty Institute, it predicted daily demand on intensive care beds running from 5000 a day for the best case, including quarantine, isolation and social distancing, to 35,000 a day if the outbreak was uncontrolled.
Modelling suggested 20 per cent of the population would become infected in the first wave - or 5.1 million people - and 1 per cent would die, adding to 51,000 deaths.
By Tuesday this week, just 7133 people had been infected,and 102 had died.
Liberal Senator James Paterson questioned Professor Murphy about the modelling on Tuesday, saying the government's policy had been predicated on it.
"On the basis of that modelling, governments envisaged that we would gave quite serious restrictions ... for up to six months," he said.
"Happily that now doesn't appear to be the case. We're now only two months in and they're being eased. So policy was predicated on six month restriction scenario is obviously going to be quite out of step for what ends up being a two month scenario isn't it."
Professor Murphy said Australia was doing much better than expected but there was "no clear model or path".
"We're all finding our way," he said. "We're all looking at the danger every day and reevaluating our position, in health as in all the other responses. So, it is a very uncertain time and we still don't clearly have the end game."
The modelling had been aimed at ensuring hospitals could cope and Australia could avoid the tragedy of places like New York. It had been calculated from the basis that Australia could not staff more than 7000 intensive care beds.
"So we looked at the modelling and said what do we have to do in the somewhat artificial situation of a community-wide outbreak to bring it down to that level," he said. "That was really the purpose of that modelling - we wanted to reassure governments collectively that we had the tools in our kit bag to manage down to within the health system capacity."
Senator Paterson asked how his advice would have differed with the benefit of hindsight, to which Professor Murphy said he would have liked to have recommended a hard quarantine earlier, but there weren't sufficient hotel rooms at the time.
"Those countries that imposed restrictions late have had terrible devastation as they bring the pandemic under control and they still have not suppressed anywhere near the level we have," he said. "So moving early was clearly the right thing to do, I'm in absolutely no doubt about that."
- For information on COVID-19, please go to the federal Health Department's website.
- You can also call the Coronavirus Health Information Line on 1800 020 080
- If you have serious symptoms, such as difficulty breathing, call Triple Zero (000)
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