The Whittlesea outbreak in Melbourne’s northern suburbs grew to five cases this morning after a man in his 60s tested positive on Monday.

The new case is a close contact of a Wollert man who contracted the virus in South Australian hotel quarantine before flying to Melbourne on May 4.

The outbreak has prompted Victorian authorities to introduce a raft of new restrictions, with masks now mandated at all indoor venues, household visitors limited to five per day and public gathering restricted to 30 people.

Victorian Acting Premier James Merlino said all five cases have been infected with the Indian variant of the virus and are linked to the COVID leak from Adelaide’s Playford medi-hotel earlier this month.

“Importantly, the genomic sequencing has confirmed that this case, these cases, originate back to the South Australian hotel quarantine outbreak,” Merlino said.

South Australian Premier Steven Marshall said, “we are very disappointed with the news that this is a link to a case here in South Australia”.

SA Health is yet to release their investigation into how transmission occurred within the Playford medi-hotel.

Deputy Chief Public Health Officer Dr Emily Kirkpatrick said a report on its inquiry, which started two weeks ago, is sitting with Chief Public Health Officer Nicola Spurrier for “final approval” after a draft was circulated last week for feedback.

“It’s an absolute priority for us in the department that we can release a report that’s not only reliable but has been verified as well [and] has gone through all of those approval stages,” Kirkpatrick told reporters today.

Kirkpatrick said she hoped SA Health would be able to release findings to the community in “the next 48 hours”.

“It’s very important we are transparent with how our medi-hotel system operates, and also for other states as well,” she said.

The premier refused to speculate on what recommendations could be contained within the report.

“We believe we’ve taken every precaution possible but if there are findings, if there are recommendations for even tighter levels of protection within our quarantine arrangements, then we will put them in place straight away,” Marshall said.

“This is going to be a very important report, we want to get it right, not rushed.

“We will be making this report available but we’ve got to finish it first.”

Meanwhile, SA authorities overnight opted to close the border to anyone in Melbourne who has been to a “tier one” or “tier two” exposure site listed on the Victorian Government’s website, as well as introducing testing requirements for travellers from the Whittlesea Local Government Area.

Victoria Health has so far identified four tier-one sites and six tier-two sites, with 35 close contacts at a swim school in Bundoora forced into 14 days isolation.

Kirkpatrick said the number of people from Melbourne travelling into SA who will have to quarantine is expected to be “in the tens”.

“We know there are a number of flights that are coming over regularly from Victoria as well as our road traffic,” she said.

“We will see numbers of people who have been in the Whittlesea LGA, and we’ve stepped up our testing capacity today – we’ve put SA Pathology on notice that they will need to make sure that they can offer that testing at the airport.”

The Adelaide Crows are also due to fly to Melbourne this week for their clash against Richmond at the MCG on Sunday.

Ticket sales for the game have been suspended with crowd number likely to be reduced, but the Acting Premier Merlino said no decision has been made yet on attendance caps for the weekend’s games.

“For footy crowds and for other events there will be a public events advisory panel which will advise of any changes [but] we’re not making any announcements today,” he said.

“We are looking at range of events, whether it’s footy or other cultural events, we will work through all of those and provide further advice.”