Health authorities are waiting to see if Saturday's Black Lives Matter protests across the nation have undermined the containment of COVID-19 in Australia.
Just a handful of new cases were reported on the weekend, but it will be nearly a fortnight before it is known if there are any spikes in cases as a result of the rallies where social distancing was almost impossible.
Deputy Chief Medical Officer Paul Kelly says while he can understand why people joined the protests, health authorities now have to be extra alert.
"We don't know if anyone in those mass gatherings were infected or infectious, and so it is a wait-and-see approach," Professor Kelly told reporters in Canberra on Sunday.
"I was encouraged to see the face masks yesterday ... those people we're doing the right thing."
Victorian Deputy Chief Health Officer Annaliese van Diemen agreed the Black Lives Matter protest in Melbourne increased the risk for cases.
"In terms of potential outbreaks related to the protest, it really will be at least a week and probably closer to two weeks before we have an idea of whether there's been any transmissions or outbreaks related to that," Dr van Diemen said.
Twenty thousand people also marched in Sydney and crowds rallied in Brisbane, Adelaide and some regional cities and towns despite public health warnings.
Federal Health Minister Greg Hunt hopes the rallies that clearly broke COVID-19 social distancing rules will not lead to a new wave of infections.
"If there is someone who is infectious in the midst of a crowd like that, that can have a catastrophic impact," Mr Hunt told ABC radio.
The Australian protests in solidarity with African American George Floyd who died while being arrested in Minneapolis, also a showed support for the Aboriginal community to highlight high levels of indigenous incarceration and deaths in custody.
Labor has attacked Finance Minister Mathias Cormann for labelling the protesters in Australia as being "reckless" and "self-indulgent" during a pandemic.
Opposition indigenous Australians spokeswoman Linda Burney described Senator Cormann's comments as "tone deaf" and "politically expedient"
Australia has now had around 7260 confirmed COVID-19 cases while the death toll remains at 102.
Worldwide, there have been at least 6,897,225 cases and nearly 400,000 deaths.
The ACT recorded its first case of COVID-19 in over a month, a male aged in his 40s, who recently returned from overseas.
But ACT Chief Health Officer Kerryn Coleman is confident there has been no risk to the broader ACT community.
"The case is, however, a good reminder of the ongoing pandemic and the need for our community to continue to observe physical distancing and hygiene measures, and for people to stay home if they are unwell," Dr Coleman said in the statement.
There were also four new cases of coronavirus in Victoria,
One is a household contact linked to an outbreak last month at a McDonald's restaurant in Fawkner and the three others are returned travellers in hotel quarantine.
But Western Australia, South Australia and Queensland all returned blank sheets, as did NSW for a second day in a row.
But Queensland is undertaking contact tracing after a Melbourne man who arrived to pick strawberries in Bundaberg was confirmed on Saturday.
Meanwhile, the Morrison government is extending some of the measures in its $1.2 billion support package for the aviation sector to ensure the industry is sustained during the COVID-19 pandemic.
"We have kept the aviation sector going by funding minimum networks to get essential personnel and critical supplies to where they may be needed," Deputy Prime Minister Michael McCormack said in a statement.
Australian Associated Press