The directive, which comes into effect at noon today, was triggered by the combined and crippling pressures created by wide-scale staff shortages across the state's health system and record-high COVID-hospitalisations, the latter of which is anticipated to well-exceed 2500 in a matter of weeks.

Health department data yesterday showed there were currently 1152 patients in hospital across the state, up from 361 on Christmas Day. Meanwhile, 4067 of Victoria's healthcare workers were furloughed on Tuesday because they had been exposed to, or infected with, COVID-19.

IN OTHER NEWS:

Under the declaration, hospitals would be able to reconfigure internal services to free up and redeploy more staff to priority areas, defer non-urgent care and, importantly, re-distribute demand driven by COVID-19 admissions across a number of hospitals.

Epidemiologist James Trauer, who heads the epidemiological modelling unit at the Monash University school of public health, said the decision - designed to relieve unsustainable pressure on the health system - proved the health system was in crisis and wholly unprepared for the surge in community transmission witnessed in recent weeks.

"This is one of the biggest crises that we've seen in the health system since I've been working as a doctor, which is nearly 20 years," Associate Professor Trauer said. "And it's certainly nothing like what we've had to deal with in the pandemic in the previous two years."

"Not only was the health system completely unprepared for Omicron, we didn't have a well-managed mitigation plan in place for how we were going to approach it to limit its transmission and pre-emptively manage pressure on our health system.

"It reflects a failure in our response to the Omicron wave."

Though all hospitals, private and public, have code brown emergency measures at their disposal, such measures are ordinarily only enlivened on an individual basis in response to extreme, short-term external emergencies, such as natural disasters or mass casualty events.

This is the first time a coordinated code brown emergency declaration has been issued for all of the state's major hospitals.

Deputy premier James Merlino said the call was warranted in order to fortify the capacity of the health system to withstand the pressure further hospitalisations and staff shortages would give rise to in coming weeks.

"We've reached a point in our healthcare system where it's juggling severe workforce shortages [with] more than 4000 healthcare workers unavailable right now," Mr Merlino said.

"It is the right time to do it now, not wait for a code brown [declaration] until two or three weeks down the track when we're seeing the impact of the peak of Omicron hospitalisations and ICU patients.

"The risks we're now seeing in COVID hospitalisations are a testament to that."

But epidemiologist Nancy Baxter, head of the Melbourne school of population and global health at the University of Melbourne, said the timing of the decision pointed to an anaemic health system cracking under the weight of the Omicron wave.

"It's not surprising that hospitals are feeling the pinch with the Omicron wave," Professor Baxter said. "What is surprising and quite remarkable is how low our hospitalisations were to lead to this [emergency] response."

"We're fortunate Omicron has proved to be comparatively less severe, less virulent, because otherwise [the hospital system] would never have been able to cope with the burden.

"And obviously this is a preventive kind of manoeuvre to try to avoid getting into an even worse crisis."

Deputy state controller of health system operations Adam Horsburgh said the manner in which the code brown declaration would be implemented would vary from hospital to hospital.

"In this particular instance, hospitals will be able to be flexible in terms of exactly how they respond at a local level, recognising the unique local demands and challenges that they face," he said.

"But some of the measures [will] include deferring or postponing non-urgent clinical services, including some outpatient services, or looking to provide some care outside of the hospital."

Mr Horsburgh added that the leave entitlements of healthcare staff could also be temporarily suspended if "absolutely necessary", while staff could also be asked to perform duties outside their normal role.

In a telling mark of how dire the situation within Victorian hospitals had become, Mr Horsburgh conceded that it would be entirely open to hospitals affected by the directive to cancel more-urgent category one elective surgery.

"We are conscious that the number of COVID admissions and therefore the pressure on the system will likely continue to rise over the next few weeks," he said.

"So, there may come a point where it becomes more challenging to maintain category one [elective] surgery."

This would mean delaying urgent procedures for people with life-threatening heart disease or cancer, something Professor Baxter said would likely have tragic consequences for those impacted.

"Category one surgeries are your non-emergency urgent surgeries, such as cancer surgeries," she said.

"The people who need [the procedure] could die if they don't get surgery."

Notably, the coordinated code brown directive could see Ballarat Base Hospital resume its role as a "COVID streaming" hospital, requiring it to admit COVID patients from other parts of the state.

Ballarat Health Services was contacted for comment but is yet to confirm how the emergency directive would impact the hospital or the wider health system in the Grampians region.

Health officials said they expected the code brown directive would be in place for a minimum of between four and six weeks, depending on when the Omicron wave finally peaked.

Meanwhile, the federal government announced that thousands of healthcare staff from private hospitals remain on standby to assist Omicron-affected parts of the country.

Several private hospitals in Victoria have already been seconded to the public system under the code brown directive.

The state's code brown declaration was announced on Australia's deadliest day of the pandemic, with nearly 70 deaths in Victoria and New South Wales combined and almost 80 nation-wide.

More than 460 people have died in Australia from COVID-19 this year - those deaths occurring at more than triple the pace experienced during last year's Delta wave.

If you are seeing this message you are a loyal digital subscriber to The Courier, as we made this story available only to subscribers. Thank you very much for your support and allowing us to continue telling Ballarat's story. We appreciate your support of journalism in our great city.