Restrictions should be tightened now to contain outbreaks with escalating COVID-19 case numbers across the country before hospitals reach capacity, in a move that would reduce the overall cost to the economy, experts say.
Australia on Tuesday reported 47,813 COVID-19 cases, the highest daily figure since the pandemic began. The ACT posted a record 926 cases of COVID-19, in a near doubling on the previous day's tally.
Professor Quentin Grafton, an economist at the Australian National University's Crawford school of public policy, said restrictions on mass gatherings and stricter density limits should be introduced now to limit the ongoing public health and economic costs of the Omicron outbreak.
"With Omicron, too little too late imposes big costs. Do more and do it better and do it earlier and the costs associated with that both in public health and in the economy will be less than just living with the virus, whatever that means," Professor Grafton said.
Professor Grafton, who last year worked on modelling that showed the benefits of lockdowns to halt community transmission, said there needed to be consistent messaging about the risks posed by the rapid rise in COVID-19 cases in the community.
"If you're allowed to go to ... a church service with a 100 people ... when there's a thousand or so cases a day now in the ACT, that's giving you the wrong message that somehow this is a safe thing to do," he said.
Professor Grafton said intensive care capacity could be exceeded in NSW within 10 days, and it was better to act before the hospitals were full.
"That doesn't mean lockdown. Lockdown means no one goes to work and nothing happens. That's a strict lockdown. I'm not suggesting or proposing that. What I am saying is you do take additional steps. That's sensible, precautionary and just smart," he said.
"I think it is better to - and it is less costly - to act now. If we have learnt anything in the last two years, we should have learnt this."
Professor Adrian Esterman, who holds the chair in biostatistics and epidemiology at the University of South Australia, also stopped short of calling for a lockdown but said many public health measures could be reintroduced in Australia without significantly harming business.
"Density limits are not going to kill a business, [but] might reduce its profit. We can put those in place, that will dampen the outbreaks down and eventually get us back to equilibrium," Professor Esterman said.
"So not to zero cases, but to a manageable number where the hospitals don't get swamped."
NSW Premier Dominic Perrottet has defended his decision to remove a series of restrictions in mid-December, but was forced to reintroduce masks and density limits in indoor settings as cases grew.
With the state now consistently recording more than 20,000 cases each day, and hospitalisations on the rise, Professor Esterman said the state's system was already under "amazing pressure".
Omicron's milder symptoms meant an individual was less likely to be hospitalised, but its hyper-infectiousness would place added strain through sheer number of cases, he said.
"I'd put $1,000 that there'll be more public health measures within two weeks," Professor Esterman said.
"NSW Health are going to have to ... they simply won't have any chance of not doing it, otherwise things would get totally out of control."
A host of European countries have reimposed tough restrictions, including lockdowns in the Netherlands, as the continent grapples with record infection rates.
Professor Esterman said it was "no surprise" to see a surge in cases on January 4 because symptoms normally took four days to appear in an infected person.
With hospitalisations typically lagging days behind new infections, he warned more pressure on the system was inevitable.
"This is all the New Year's Eve factor coming in here. It's spot on for another big wave of infections. Usually around a few days after that, the hospitalisation starts going up," he said.
But infectious diseases expert Professor Catherine Bennett said the huge queues for PCR tests had lead to a delay in results, which meant the lag between case numbers and hospitalisations was much smaller.
Professor Bennett, who holds the chair in epidemiology at Deakin University, said a person tested after two days of symptoms was often receiving their results a week or more after their initial exposure.
"That's probably the same time it takes someone to get infected and, if they're going to get serious symptoms, to end up in hospital," she said.
"So case numbers aren't predicting what's going to happen in hospital next week. They're more closely tied to what's happening today."
Rather than restrictions returning across the board, Professor Bennett expected tailored "local responses", including tougher rules in regional areas without easy access to hospitals.
The ACT has consistently raised the alarm over hospital capacity, with the territory serving a catchment area of over 200,000 NSW residents.
"If you've somewhere like Ballarat seeing a spike in cases, you know your local services won't be able to cope. It's a problem if you're going to transfer people to the city," Professor Bennett said.
"Then you might discourage people [from] coming to Ballarat, and ask for the cafes to only serve outdoors or to have density limits."
With intensive care capacity remaining at manageable levels in major cities, Professor Bennett said "more clean messaging" on the basics - mask wearing, social distancing - was needed while "conceding we won't get everyone on board".
She warned going down an "enforcement pathway" could lead to resistance from some people who were otherwise "self-regulating their own behaviour".
"Then we're getting to this spiral, again, of having to have more severe rules than we need, just to try and get a basic level of compliance," she said.
"Given the translation to hospitalisations is manageable, except for [among] staff ... we should be working with the community to them with the information they need to stay safe."
The calls for tightened restrictions come ahead of a national cabinet meeting on Wednesday, where state and territory leaders will discuss health system capacity and COVID-19 testing.
The ACT's daily case tally jumped 80 per cent on Tuesday, up from 514 cases on Monday. There were 13 people in hospital at 8pm on Monday night with COVID-19, including one person in intensive care who required ventilation support.
A new epidemiological snapshot of the territory's COVID-19 situation will be released on Wednesday, when the chief health officer, Dr Kerryn Coleman, is expected to speak to the outbreak situation publicly for the first time since December 23.
ACT Health Minister Rachel Stephen-Smith on Monday said Canberra hospitals could be treating "a few dozen" COVID-19 patients by the end of the week, as the ACT health system readied itself for the highest caseload it has managed since the pandemic began.
Ms Stephen-Smith said health authorities had expected before Christmas the hospitalisation rate to be higher by the new year, and projections always took into account the potential impact of COVID-19 cases in the surrounding NSW region.
An ACT government spokesman told The Canberra Times in August there were 28 intensive care beds, which could be scaled up to 51 beds and then run at a surge capacity of 110 beds. Health authorities are expected to provide more detail about hospitalisation projections at an update on Wednesday
NSW set records for COVID-19 hospitalisations and daily caseloads on Tuesday, after the state reported 23,131 new cases on Tuesday, 2337 more than the previous day.
There were 1344 people in the state's hospitals with COVID-19 on Tuesday, 78 more than the previous record set on September 21 when NSW was in the middle of an outbreak of the Delta COVID-19 variant.
Victoria reported 14,020 COVID-19 infections on Tuesday, with 25 additional hospitalisations bringing the total number of patients to 516.
However, true case numbers in Australia are thought to be significantly higher. High test-positivity rates and limited availability of PCR tests to confirm infections mean the true COVID-19 infection rate is higher than the reported figures.
ACT health authorities are working to develop a system for people to self-report their positive rapid antigen test results, which would likely be included in official figures of COVID-19 infections.
However, population estimates of COVID-19 infections, similar to what are used for seasonal influenza, are still some time away, the Health Minister, Ms Stephen-Smith, said.
"It is quite likely that we'll move from a system where we're only counting positive PCR results to a system where we incorporate rapid antigen test results, maybe with symptomatic presentation. [We would move] potentially to a system where we're also estimating on the basis of population estimates," she said.
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