Victoria's coronavirus testing expert has confirmed one Melbourne resident spread the coronavirus in two regional areas.

Speaking to 3AW this morning, Department of Health and Human Services Commander of Testing and Community Engagement, Jeroen Weimar, said the individual was originally linked to the Chadstone shopping centre butcher shop cluster in Melbourne.

It is understood the positive case was permitted to work and travel in the state, and ate at the Oddfellows cafe in Kilmore during a work trip, with six Kilmore residents later contracting the virus.

The same person then travelled to Shepparton on September 30, with the city later recording three COVID-19 cases, Mr Weimar confirmed.

He said the person only informed authorities of that crucial stop yesterday - even after case numbers in Shepparton started to climb.

"Something clearly happened on the 30th of September between that individual and the people at the tyre shop which meant the virus was able to spread, very similarly to what happened in Kilmore," Mr Weimar said on 3AW.

"The individual, who had a work permit to travel into regional Victoria, as well as stopping off at Kilmore also stopped off in Shepparton … The information was unfortunately not forthcoming until last night.

"The contact tracing is really swift but we're only as good as the information we get and if we don't know people have been to Shepparton then it's very hard to contact trace in Shepparton."

The ABC is reporting the individual in question is a truck driver who was permitted to travel but not to dine in the Kilmore cafe where that outbreak originated.

The man then drove to Benalla and visited a tyre shop - and one of the new Shepparton cases is a worker from a local tyre centre, which allowed authorities to "join the dots" before the truckie admitted to stopping by Shepparton as well.

Victoria's Chief Health Officer Brett Sutton has also posted a stern message on Twitter urging people to be "honest" about their whereabouts.

While not specifically referring to the superspreader, Prof Sutton said withholding information could kill.

"To be absolutely clear, delays in cluster investigations are not about the response, which is immediate," he posted.

"We need everyone to be honest about who their close contacts are, where they work, and where they've been. Every time. For everyone's sake.

"Others are put at genuine risk when we can't follow-up people who have been exposed or places that everyone needs to know about as a prompt for testing and self-isolation. With timely, honest information we can protect Victoria. And defeat this virus."

Originally published as Single superspreader behind two clusters

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