Epidemiologists say Victorians can expect an increase in COVID-19 cases due to the highly transmissible new Omicron variant, despite current case numbers being relatively stable.
New South Wales Health Minister Brad Hazzard said yesterday the new sub-variant of Omicron, BA.2, was driving an increase in COVID-19 cases in the state and was quickly becoming the dominant variant.
On Friday, Victorian Health Minister Martin Foley said the rise in cases in New South Wales "doesn't come as a surprise" and Victoria seemed to be following the same trend.
"We've seen a steady increase in the BA.2 sub-variant," he said.
He said that because of the growth of BA.2 combined with the colder weather, Victoria would likely see a rise in cases.
"We've been saying for some time, that as we head towards autumn and winter we would expect to see an uptick in cases," he said.
Victoria's seven-day average for daily infections has been steady for the past fortnight and sits at around 6,447.
Adrian Esterman, professor of biostatistics and epidemiology at the University of South Australia, said Victoria could soon be in a similar situation to New South Wales because of the new sub-variant and a relaxation of public health measures.
He said BA.2 was about 40 per cent more transmissible than the original Omicron strain, with a similar transmissibility to the highly contagious measles.
"Omicron BA.2 is now approaching the most contagious disease we know," he told the ABC.
He said BA.2 would likely be the dominant variant in Australia in a couple of weeks.
Should we bring back restrictions?
Professor Esterman said state governments should consider bringing back long-term, low-level restrictions that did not impact people and businesses too much, like mask mandates for indoor settings and QR codes.
"Epidemiology 101 says if you see an increase in cases you start putting on public health measures to reduce them," he said.
"The problem with increasing case numbers is you get a lot more people with long-term health problems, which the government never seems to think about."
But public health physician Nathan Grills, from the University of Melbourne, said there was probably no need for new restrictions even if Victoria's current cases numbers doubled.
"I think we will see potentially a small increase, the numbers might double in the next six to eight weeks," Professor Grills said.
"I think that still puts us way below overwhelming our health system."
Professor Grills said the severity of BA.2 seemed to be relatively similar to the original Omicron strain.
He said this should be reassessed as new data emerged.
Current case numbers stable
On Friday, Victoria reported 10 further COVID-19 deaths and 6,811 new infections.
The number of people in hospital with the virus has remained stable at 185, down slightly from 188 patients on Thursday.
Of those in hospital, 27 are in intensive care, with three patients on ventilators.
There are now 46,263 active cases in the state.
Around 94 per cent of Victorians aged 12 and above have received two COVID-19 vaccine doses and almost 62 per cent of adults have received three doses.
New workplace vaccine requirements
Vaccine mandates for some workers will come into effect this weekend.
Workers in a range of industries, including residential aged care, emergency services and food distribution, will need to show evidence that they have received three doses of a COVID-19 vaccine to work on site.
More details about the new vaccine mandate and a full list of workers it applies to are on the Victorian government's website.
More waves of infection are 'inevitable'
Mathematical epidemiologist at the University of Melbourne, James McCaw, said the virus would continue to spread.
"Vaccination and past infection are expected to protect against severe outcomes, but will not fully prevent transmission of the virus," Professor McCaw said.
"New waves of infection, globally and in Australia, are inevitable. But their impact is unknown."
He said Australia's approach was suitable, but warned people to remain cautious.
"Our current settings — schools back enabling education, borders open enabling travel for work and holidays — are appropriate, with benefits for overall health and well being, education, and the economy," he said.
"We must remain prepared to respond. That requires people to remain vigilant, in essence to continue to take it seriously," said Professor McCaw.
