Counties Manukau DHB is preparing for the impact a surge in Omicron cases could have on staffing levels and hospital services.
But despite the fact the outbreak is expected to continue to grow, a spokeswoman says it is hard to predict exactly how it will play out.
She said the DHB was preparing for a number of possible outcomes and how staffing levels could be managed.
"There are many possible scenarios that could play out if community transmission of Omicron escalates, so this is difficult to predict," the spokeswoman said.
She didn't provide any hard data on what percentage of its total frontline workforce it expected to have in isolation or quarantine at the peak of an outbreak.
But a healthcare worker from Middlemore Hospital, who asked not to be named, said staff were expecting a wave of cases which would affect medical workers.
"We are gearing up for massive staffing losses due to staff being in isolation due to Omicron over the next two months," they said.
"There's a lot of anxiety about how we're going to cope with the influx of patients, but also the numbers of staff who may have to be stood down because they have Covid."
They said with nursing shortages already at breaking point something had to give.
New Zealand Nurses Organisation manager of industrial services Glenda Alexander said the union had been in constant contact with DHBs and healthcare providers about the developing situation.
She said most already had contingency plans to deal with losing staff due to Omicron.
"But the issue for us in health is we already have a stretched workforce in terms of staffing. So if we lost, for instance, 25 per cent of our workforce it's going to put enormous pressure on hospitals," Alexander said.
"And even if Omicron does have much less of an impact than we think, it will impact on the health system because of understaffing which has been an ongoing issue for years. We just don't have the capacity in the system, so it could be a real challenge."
University of Auckland epidemiologist Rod Jackson said while mortality and hospitalisation rates for Omicron are lower, the fact it is so contagious means it could have a bigger impact on workplaces.
He said as the outbreak grows it is highly likely that many employers will see increasing numbers of staff in isolation through either contracting the virus, or being close contacts.
"I think that's been a big concern with Omicron internationally," Jackson said. "People might not be sick enough to go to hospital, but they can't go to work."
And hospitals, like all workplaces, will be affected.
He said as case numbers increase we may see a shift towards shorter isolation times for people who have either been exposed, or have the virus.
"So it's all about getting the balance right. But at the moment we're just trying to keep it out for as long as possible."
It follows the government's announcement on Thursday that critical workers will be able to end self-isolation early if identified as a close contact of a Covid-19 case.
The changes will cover those who work in a number of industries, including food production, key public services like health and emergency services and utilities like power and water and transport. But the scheme won't start until the next phase of the Omicron outbreak, when there is a marked increase in case numbers.
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