92 people were arrested yesterday and rallies are again expect today.
Epidemiologist Nancy Baxter has told 7 it's likely they were highly infectious while among the crowd.
"Given that somebody was there and went into hospital shortly after, means that they probably had a viral load at the protest. I certainly would not be surprised if a number of positive cases came from that event," she said.
Meantime, health staff are being warned not to wear their uniforms in public in Melbourne after reports some have been abused and a nurse spat on.
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