The Boxing Day Test is unlikely to have been a major coronavirus seeding event as more cases would have emerged by now if that were the case, according to epidemiologist Catherine Bennett.
But she said it was still useful to ask people who were at the MCG and Chadstone to get tested.
"If you have a major seeding event, you're much more likely to find it because you would expect more cases — at least one or two of those — to come forward and be tested and as soon as that happens contact tracing then ties them back to a venue," she said.
"So it's unlikely it's a big seeding event."
Professor Bennett said Melbourne's mystery case may indicate several other cases of COVID-19 have crossed the border to Victoria from New South Wales.
The blog is now closed. Here are the coronavirus news highlights from Wednesday:
- Masks will be mandatory at Thursday's SCG Test and more suburbs have been added to the list for people banned from attending
- National Cabinet will hold a special meeting on Friday to discuss protections from the highly infectious UK variant of coronavirus
- WA reports three overseas cases of coronavirus
- NSW records four locally acquired coronavirus cases
- Vic records one new locally acquired coronavirus case
- WA paramedic now in hotel quarantine after possible PPE breach with positive case
- The MCG has been declared a potential coronavirus infection site after a man who attended day two of the Boxing Day test returned a positive test
- The Grammys will be postponed in LA due to overwhelming number of COVID-19 cases
- Vic Government delays return-to-work schedule amid Black Rock cluster and new mystery case
- A 33-year-old woman briefly escaped quarantine at Howard Springs (NT) after scaling a fence. She now back in quarantine
