"This is a once in a hundred year type event".
Every person entering Australia will have to spend a fortnight in self-isolation from Monday, as the federal government scrambles to stop the spread of coronavirus.
Morrison has already flagged a stimulus package worth around A$17 billion and said on Wednesday the government was "considering quite extensive further economic measures" to boring the impact on the economy.
He rejected growing calls for the government to close all schools, as has been done in other countries, saying that the impact on society and the economy from such a closure would be "severe", costing "tens of thousands of jobs".
Indoor non-essential gatherings will now be limited to 100 people, while a 500 person limit remains in place for outdoor gatherings. This includes airports, public transport, hotels, prisons, courts, shopping centres, offices and factories, and construction sites. "No more scant attention to hand hygiene".
Disability and aged care centers are open but restricting visitors.
Only one short daily visit of at most two people per resident is allowed.
Finally, Morrison stressed in no uncertain terms that Australians should immediately stop panic-buying and stocking up on supplies.
"We haven't seen this sort of thing in Australia since the end of the First World War".
Opposition Leader Anthony Albanese said his son had reported customers at the major supermarket where he works shouting at staff over product shortages. "If people could be kind at this time, be patient", he said.
With the death toll of the Wuhan coronavirus (COVID-19) rising to 7,970 worldwide, Australian Prime Minister Scott Morrison on Wednesday (March 18) announced that citizens must cancel all non-essential overseas travel and declared the pandemic a "human biosecurity emergency".
All people arriving from overseas must self-quarantine for 14 days and cruise ships are barred from Australian ports for at least 30 days.
Many office workers have also begun working from home as Australians practice social distancing measures.
Shortly before Morrison's statement, the government unveiled a A$$715 million ($430 million) aid package for airlines, including waivers on domestic air traffic control fees.
Instead, he urged Australians to exercise caution in social interactions: "Keep away from each other where possible".
It is also calling for concessional loans, wage subsidies for extended sick leave, and support for small businesses to invest in technology that will let their staff work from home.