Contracting tracing experts have started to investigate a potential cluster that could occur following confirmation a Black Lives Matter protester had tested positive for Coronavirus.
The man, aged in his 30s, was among 10,000 people who attend the rally in the CBD last weekend.
It is reported he did not experience symptoms until 24 hours after the protest and wore a mask but there is a worry he was contagious at the demonstration.
A warning has been issued for a potential chain of infection.
Chief Health Officer Professor Brett Sutton has not and will not identify the man and it is not known if he had the COVIDSafe App.
The Department of Health will now have the task of identifying people who he came in close contact with and each confirmed case will then need to be interviewed.
Anybody who he came into contact with, will have to self isolate.
The Australian Health Protection Principal Committee maintained those who were part of last weekend’s protests do not need to self-isolate or be tested unless they experience symptoms or are identified as a close contact of the infected protester.