Victoria is on track to stabilise its Covid case numbers and reopen later this month, despite reporting a national record of 1,763 infections on Tuesday.
The premier, Daniel Andrews, said the government was still committed to “doing everything that we can to deliver the roadmap”, even though Covid case numbers had been above 1,000 for six days running.
He said he was confident the state would still meet its reopening date of 26 October – the day Victoria was expected to achieve a 70% double-dose vaccination rate.
More freedoms were then expected when Victoria hits an 80% vaccination rate. This was due on 5 November.
“I have no advice on altering anything on the roadmap,” Andrews said.
“I want to try to give people as much freedom as fast as I can, as safely as possible.”
The Burnet Institute modelling, which helped to inform Victoria’s roadmap out of lockdown, suggested Victoria’s peak would not come until some time between 19 and 31 October, when daily new diagnoses were projected to reach 1,400 to 2,900 cases.
The chair of epidemiology at Deakin University, Prof Catherine Bennett, said that the state had exceeded 1,700 cases about two weeks earlier than the model projected, but this was not yet cause for concern.
Based on current rolling averages, she thought the state would hit between 2,000 and 2,200 cases in late October, but that would be “still within the range of the model”.
“The good news is our hospital rates are actually lower than the model is predicting,” Bennett said.
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The Burnet model suggested that at 1,400 to 2,900 cases, there would be between 1,200 and 2,500 people in hospital and between 260 and 550 of those would be in intensive care.
On Tuesday there were 517 people in hospital with Covid-19 in Victoria, 101 of those in intensive care.
“It is still early days for hospitals, and we might still see a hospital peak in a week or so, as current cases start to develop more serious illness,” Bennett said. “There is a risk hospital rates still need to catch up to the model. But as long as we don’t exceed the model, I am hopeful authorities can manage it.”
Bennett said the reproductive, or reff, rate was key to continuing with plans to reopen the state.
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The reff rate for the virus on Tuesday was 1.2, which means for every 10 people who test positive, a further 12 people could be expected to become infected in the next generation of spread. On Saturday, the reff was higher, at 1.6, following high case numbers throughout the end of last week.
“When we look at numbers, we look at rolling averages rather than a single day, and the good news is that our reproductive number is coming down closer to one again,” Bennett said.
Once the reff falls below one, the spread can be contained and the infection will eventually die out. Bennett said if the reff could stay low, this would be more important than overall case numbers. New South Wales, for example, had consistently managed to hold its reff between 1.2 and 1.4.
“Victoria had lower case numbers over the weekend, and today’s high number is probably catch-up for those who put off testing over the weekend,” Bennett said.
“Now, clearly, there is something in the background like protests or grand final day parties that has pushed the number up, but I’m hopeful that because it’s against an even higher background rate of vaccination, we can recover and get back to a plateauing of cases, or at least a much slower rise, in the next week or so. It will be concerning, however, if we continue to see big rises over the next few days.”
With cases rising, the state will from this week stop publicly listing tier two exposure sites, because there are so many of them that contact tracers cannot keep up. Instead they will focus on listing the most high-risk exposure sites, known as tier one sites.
Prof Margaret Hellard, the Burnet Institute deputy director who oversaw the modelling, said the work suggested dozens of scenarios, including those that were still within the range of Victoria’s Tuesday case numbers.
“We constantly are recalibrating the model based on updated data, but we don’t do it every day, we wait for a few weeks of data because that average is more reliable, and then we recalibrate to see where we’re on track,” she said.
“There’s a wide range as to where we might be in Victoria on a particular date, and that’s why I always say people have got to be incredibly careful not to see modelling as forecasting.”
