Victoria records three new COVID cases and additional mystery infection

But Dr Fauci said people are unlikely to be able to go about their normal lives until at least the end of next year.

"I think it will be easily by the end of 2021 and perhaps into the next year before we start having some semblance of normality," Dr Fauci said via video link.

"If normal means you can get people in a theatre without worrying about what we call congregate-setting super infections, if we can get restaurants to open almost at full capacity."

But the director of the United States' National Institute of Allergy and Infectious Diseases said stubborn anti-vaxxer beliefs, political division and the self-interested meddling of politicians would all make the job of immunising the world against COVID-19 tougher.

Foot traffic through some Melbourne CBD streets was back to 80 per cent of pre-COVID levels on Wednesday as shops, cafes and restaurants were allowed to reopen.

But one of Victoria’s leading economists urged caution, saying the uncertainty around the prospects for both the state and national economies was unprecedented, despite the cautiously upbeat assessment this week from the Reserve Bank of Australia.

"The recovery of the Victorian economy depends on the degree to which those industries have stayed afloat," RMIT economist Leonora Risse said.

"It is my expectation that we will see a recovery but that recovery will plateau, it won’t go back to the full force pre-pandemic levels because we don’t have that international [visitor] market."

The Age was unable to obtain any real-time figures on consumer spending for Melbourne’s first day of freedom but data on pedestrian movements in the CBD on Wednesday points to better times ahead for city retailers, after months of keeping their doors shut.

At lunchtime on Wednesday, 1916 people were logged walking through Bourke Street Mall, almost five times more than the average foot traffic at that time over the past month, with above average foot traffic also recorded outside Flinders Street and Southern Cross stations, at Melbourne Central and on Lygon Street.