"What Victoria has done is surely a template that the other states and territories might follow and the federal government should encourage this adoption as it would be so much easier for states and territories using the same system," Professor Blakely said.
Victoria's new traffic light system builds upon the hotspot approach supported by national cabinet and creates three zones and responses to outbreaks.
"I would be loath, in fact I would refuse if I was asked to try and write down the exact recipe for what becomes a red zone and what is an orange zone," Professor Blakely said.
Professor Bennett said if close contacts of the last cases all test negative and/or were quarantined before infectious, then this would be reassuring and may soon lead to being downgraded to green.
"Red is evidence of wider community transmission where not all cases can be linked, or where there is doubt about whether all close contacts can be identified and quarantined," Professor Bennett said.