State and Territory Governments have legislated public health orders to ensure protection of the Australian public. These orders cover a range of measures including directing when people must quarantine or self-isolate.
Quarantine
The quarantine orders allow people to be detained when they enter a State or Territory - For example, see Public Health (COVID-19 Air Transportation and Maritime Quarantine) Amendment Order (No 2).
Self-isolation
Self-isolation orders direct that a person diagnosed with COVID-19 must self-isolate in their residence until medically cleared. These orders also extend to a person who has been identified by an authorised contact tracer as a close contact of a COVID-19 case, requiring that person to self-isolate for the period of time determined by the authorised contact tracer. See Public Health (COVID-19 Self-Isolation) Order (No 3) 2020.