Australia declares 'human biosecurity emergency'

Morrison upgraded the official travel advice for Australians thinking of heading overseas to an unprecedented "Level 4: Do not travel" for the entire world. Anybody who travels during a Level 4 ban is warned that the Australian government may not be able to assist if they get into trouble while abroad, according to the government's official SmartTraveller website.

Morrison said schools would remain open, citing expert health guidance, and reiterated the need for social distancing and good hand hygiene to curb the spread of the virus.

He also scolded hoarders, saying it was "one of the most disappointing things I have seen in Australian behaviour in response to this crisis."