Figures released by the Department of Health show that 732, or about 10.3 per cent, of confirmed Covid-19 cases in the country have been locally acquired with no contact identified.
This means hundreds of people have caught the virus in Australia but the source of the infection could not be found.
Protesters gather outside Parliament House in Melbourne on May 10 in opposition to the coronavirus lockdown. AAP Image / Scott Barbour
"Knowing the source of the infection is an integral part of stopping the spread of Covid-19," according to the Department of Health.
Though new daily cases of the virus have decreased dramatically in Australia, there are still cases emerging which proves people can't become complacent.
Six crew members from a live export ship off Perth have tested positive for coronavirus, with Western Australia Premier Mark McGowan labelling the situation "extremely concerning".
"For the time being, the remaining 42 crew members, who I am advised are currently well, will remain on board the ship and will be monitored and undergo health assessments as required," he said.
This image from video shows a freight ship in Fremantle where a coronavirus cluster was detected on Tuesday. AP Photo / AuBC, CHANNEL 7
"But I suspect it is probably more than likely that more crew members may become infected with the virus. This is an extremely concerning situation that we find ourselves in."
McGowan said the situation was "serious news" that he hoped not to have to deliver.
"I thought these kinds of situations were behind us. It goes to show that strong border controls are important as we continue to handle this worldwide health crisis."
South Australia has also seen a re-emergence of the virus after a British woman in her 50s was diagnosed with the illness in Adelaide.
The new case brought the state's total to 440, with the number rising for the first time in 18 days.
Meanwhile, Prime Minister Scott Morrison has revealed almost 100,000 Australians have written to him to share their personal experiences during the pandemic.
Speaking at the National Press Club on Tuesday, Morrison said he received a heartbreaking email from three children in Western Australia that "completely floored" him.
"Their father, terminally ill, and they told me they understood that dad's funeral would have to be small and they wanted me to know that they were okay with that, because, they said, it will help keep hospitals available for other patients with cancers and diseases," he said.
The Sydney Opera house at sunset on March 20, a time when tourists usually flock for photos. Photo / Matthew Abbott, The New York Times
Thousands of other Australians have contacted the Prime Minister to share how they had been impacted over the past few months, with Morrison saying many people have suffered during this time.
"So many have suffered and they continue to hurt, right here, and right now. Lost jobs, reduced hours, seeing their family businesses shut, having to close those doors, retirement incomes shrink, loved ones kept apart," he said.
"It has been a time of great uncertainty as Australians have had to come to terms with sudden and profound changes to their lives."
