The positive test results came from 51,033 Covid tests conducted in the state and there were 20,585 vaccinations administered on Tuesday. It comes as health authorities listed six shopping precincts of “particular concern” and warned how quickly the virus was spreading from “stranger to stranger”. Victoria’s Covid testing commander Jeroen Weimar warned that at least four of the state’s more than 50 locally transmitted cases had come from “fleeting” contact between Victorians. “This is stranger-to-stranger transmission.”Woolworths is providing Everyday Rewards data to assist with contact tracing, while Coles is also handing over details from its Flybuys customer loyalty program. “Contact tracers should be using anything they can from a store, particularly if they don’t have a check-in system,” she said.