Victoria now has 10 cases in total of the Omicron variant, including one who was infectious in the community on Friday December 10.
There are over 850 people in isolation as a result of the community transmission, which occurred in Fitzroy and Collingwood.
The Peel Hotel in Collingwood was occupied with about 400 people during the time the COVID-positive person attended, and the Sircuit Bar in Fitzroy had about 450 people in the venue at the time.
The Omicron case visited the Sircuit Bar between 9pm and midnight Friday night and the Peel Hotel between 11:30pm on Friday and 3am Saturday morning.
Those who were at the venues during these times will need to isolate for seven days regardless of vaccination status.