How our response may wipe COVID-19 off the map

Buoyed by the continued fall in new coronavirus cases, Australia’s top doctor says it’s possible that we could eradicate COVID-19 in some parts of the country.

AUSTRALIA’S top doctor has raised the possibility of coronavirus being killed off in the country – a feat thought impossible weeks ago as the Morrison Government ramped up the number of ICU beds.

Chief Medical Officer Brendan Murphy said there were 6457 cases yesterday and 63 people who had died of COVID-19 – and fewer than 50 new cases a day for the past few days.

In what has surprised the nation’s leaders and medicos, the continued fall in new coronavirus cases, and few cases of community transmission, has meant the diagnosis has dramatically switched to the possibility of eradication.

Asked if it was possible to have no more cases in Australia, Prof Murphy said: “It’s quite possible we could eradicate the virus in parts of the country.

“Some states have had no cases for some days and small numbers of cases all imported.

“We are on the same trajectory as New Zealand which is heading for eradication and if we achieve complete lack of transmission and no cases that would be great.

“But we don’t know whether there are asymptomatic cases circulating. You cannot relax your surveillance and control mechanisms because you have not detected new cases for a period of time.”

Social distancing measures may soon be downgraded if Australia’s coronavirus numbers keep falling.

Prof Murphy said there was not a lot of difference between an “aggressive suppression strategy and an eradication strategy with the exception that we don’t feel the need to hold the country very seriously in lockdown until we have no cases”.

Prime Minister Scott Morrison said eradication was possible but suppression was the best path for Australia.

Releasing modelling yesterday, Prof Murphy said Australia had one of the best detection rates in the world, as 92 per cent of all symptomatic cases had been identified.

Describing modelling as “nowcasting”, he said the modelling used data to best identify Australia’s coronavirus risk.

The London School of Hygiene and Tropical Medicine provided the modelling.

WHAT IS THE EFFECTIVE REPRODUCTION RATE?

A key measure indicating COVID-19 is reaching a controllable level has been reached, in an encouraging sign that social distancing measures and restrictions are paying off.

Chief Medical Officer Professor Brendan Murphy yesterday revealed the effective reproduction rate – which is the number of people a single case infects on average – had fallen below one in every state, except Tasmania where there is a breakout in the northwest.

For suppression strategies to be deemed effective, that number – known as the Reff – needs to stay below one.

“Obviously when we get that below one we can control and reduce the outbreak,” Prof Murphy said.

“So it’s a very good measure of our mitigation and control strategies.”

Prof Murphy said an effective reproduction rate below one was “showing that the epidemic is reducing” and it could reassure the public that the response measures are working.

He said Tasmania’s number had skyrocketed after the recent outbreak related to hospitals in the state’s northwest.

“That shows how sensitive this measure is. That will drop away very quickly as the outbreak is brought under control,” he said. “You can see the other three states, NSW, Queensland and South Australia, the effective reproduction rate is well below one, showing that the epidemic is reducing.”

Prime Minister Scott Morrison also praised the figures and said the Reff was a key measure of success moving forward.

“On the road out, there are important metric, benchmarks, we are advised to day that will inform the National Cabinet decisions about the easing of restrictions when that is deemed possible, and the most important of those is what it’s called the effective reproduction rate,” he said.