The number of new cases grew sharply, until reaching about 350 per day on 22 March. The numbers stayed around 350, and then started falling at the beginning of April. At the end of April it was under 20 cases per day. As of 15 February 2021, there were 28,098 cases and 908 deaths in Australia.
A virus that caused a respiratory illness was first seen in Wuhan City, Hubei Province, China, in December 2019. It reported to the World Health Organisation (WHO) on 31 December 2019. WHO declared the outbreak a Public Health Emergency of International Concern on 30 January, and a pandemic on 11 March.
On 23 January, passengers on flights from Wuhan to Sydney were checked when arrived. They had to say if they had a fever or thought they might have the disease. .
On 25 January, the first case of a SARS-CoV-2 infection was reported. A Chinese person arrived from Guangzhou on 19 January. The person was tested and received treatment in Melbourne. On the same day, three other people tested positive in Sydney after returning from Wuhan.
Nine cases were recorded in January. From 31 January, non Australians returning from China had to stay for two weeks in a third country before being allowed into Australia.
By 6 February, three people coming back from a tour group in Wuhan were found to have the virus in Queensland. Twenty-four Australians were infected with the virus on the "Diamond Princess" cruise ship. Eight were sent to Darwin for two weeks of quarantine. On 27 February, the prime minister put in place the Australian Health Sector Emergency Response Plan for Novel Coronavirus (COVID-19), On 29 February, after an infected person came back to Australia from Iran, the government made all people who had been in Iran go into quarantine. They had spend two weeks in a third country before being allowed into Australia. There were 14 new cases in February, bringing the number of cases to 23.
On 1 March, the first person in Australia died from COVID-19. He was a 78-year-old Perth man, who was one of the passengers from the "Diamond Princess."
On 2 March, four new cases were reported. Two of the cases were from people who had got the virus in Australia. They were both in New South Wales. One person got the virus from a close relative and the other was a health care worker. Another case found on the same day was a man from Launceston. He had been on a flight from Melbourne. He was treated at the Launceston General Hospital; the first case in Tasmania.
On 4 March, a 95-year-old woman died at an aged care home in Sydney. This was the second death in Australia.
On 7 March, a doctor in Victoria had tested positive for COVID-19. The doctor had been in the United States. From 2 to 6 March, the doctor had treated 70 patients at a clinic in Melbourne and two patients at an aged-care home. The clinic was closed, and his patients were told to self-isolate. People who had been on the same flights as the doctor were warned. The doctor believed he only had a mild cold and was fit to return to work.
On 8 March, an 82-year-old man died at aged-care home in Sydney, and was the third person to die in Australia.
On 9 March, a teacher in Melbourne got the virus from her partner who had been on the same flight from the US with the Melbourne doctor.
On 12 March, the ACT announced its first case, the 142nd case in Australia. Actor Tom Hanks and his wife Rita Wilson said that they had tested positive and were in isolation.
On 12 March, the Prime Minister said the government would spend $17.6billion to "protect Australians' health, secure jobs and set the economy to bounce back" from the crisis. In Western Australia upgrades to the Peel Health Campus were postponed so that it could safely treat people who had the virus.
Victoria had nine new cases. A McLaren Formula One team member tested positive for the virus. This brought the Victorian total to 36 and the national total to 175. Peter Dutton the Home Affairs Minister for Australia was diagnosed in Queensland. The Victorian government stopped all jury trials to limit the spread of the virus.
The University of Queensland closed after three students tested positive for the virus. Western Australia, like New South Wales, stopped schools from organising gatherings of over 500. Susan McDonald, a Queensland senator, said she was infected with the virus. New South Wales Liberal senator, Andrew Bragg, was the third Australian politician to test positive. On 18 March, a human biosecurity emergency was declared by the Governor-General, David Hurley, under Section 475 of the "Biosecurity Act 2015".
The cruise ship arrived in Sydney on 18 March and 3,500 passengers left the ship. 79 passengers had tested positively for the virus by 1 April. also arrived on 18 March. On 2 April 34 passengers and 5 crew members were found to have the virus in New South Wales alone. arrived on 19 March. On 2 April 11 cases had tested positively for the virus in New South Wales alone.
The cruise ship let 2,700 passengers off the ship in Sydney on 19 March. On 20 March is was said that 13 passengers had been tests and three had the virus. New South Wales health authorities asked all passengers to go into self-isolation.
On 19 March, Qantas said it would stop about 60% of domestic flights, put two thirds of its employees on leave, stop all international flights and stop using 150 of its aircraft from the end of March until at least 31 May 2020. This was because the government had put in travel restrictions to stop the spread of COVID-19.
On 22 March, the government said it would spend another A$66bn, bringing the total assistance to A$89bn. They doubled the money for people on income support, made it easier to get the Jobseeker's allowance, and gave grants of up to A$100,000 for small and medium-sized businesses.
On 24 March one passenger from "Ruby Princess" had died and 133 on the ship had tested positive. On 28 March 284 passengers had tested positive.
On 25 March the National COVID-19 Coordination Commission (NCCC) was set up by the Prime Minister. This would give the government advice on how to deal with the pandemic.
The number of new infections began to drop, from around 360 per day for the period of 23 to 27 March, then down to 190 in 28 March and 100 on 29 March. However, there was an expected and sudden increase in deaths.
The cruise ship arrived at Fremantle on 27 March. Most of the 850 passengers flew home from Perth to Germany on 28–29 March. 41 passengers and crew tested positive to COVID-19 and were treated in Perth hospitals.
As of 30 March, at least 440 passengers from "Ruby Princess" had tested positive for the virus. As of 31 March 2020, five of them had died.
On 30 March the Australian Government said it would spend $130 billion on the "JobKeeper" wage subsidy program. They would pay employers up to $1500 a fortnight for people that had worked for that business for over a year, if the business was losing money because of the pandemic.
On 31 March, six baggage handlers from Adelaide Airport had tested positive. As a result, about 100 other people from the airport had to self-isolate, stopping all flights to and from Adelaide.
On 1 April, the Western Australian State Government put limits on travel between regions of Western Australia.
On 2 April, the number of cases in Victoria was over 1,000, including over 100 healthcare workers.
On 5 April, New South Wales Police looked to see ifpeople who owned the "Ruby Princess", had broken Australian and New South Wales state laws, by not telling anyone about COVID-19 cases on the ship.
On 6 April, government said that 2,432 people had recovered; this is more than a third of the total number of cases.