As the state reported another 38,625 infections on Friday, NSW Health released research that predicts the impact of the Omicron variant on the health system.

Taking into account the general health of NSW's population, vaccination rates and new data on the severity of Omicron, three scenarios were mapped.

The worst of them predicts 6000 people could be hospitalised at the peak of the outbreak, expected in the third or last week of January.

Some 600 of them would be in intensive care.

"Overseas experiences have shown that this will rise quickly and pass quickly," NSW Health Deputy Secretary Susan Pearce told reporters on Friday.

"We believe by the middle of February we will be certainly well past the peak of this."

The "most realistic" model predicts 4700 beds will be needed at the peak, 273 of them in ICU.

Comparatively, at the peak of the Delta outbreak in September, there were 1266 people in hospital with infections and 244 in intensive care.

Under the moderate model, hospitalisations would be almost four times what they were at the Delta outbreak peak, but ICU admissions would only be up about 11 per cent.

In the best case scenario, only 3158 people will be hospitalised and the number in ICU will peak at 270.

There are 9500 beds available in public hospitals across the state, and at least another 3000 in private hospitals.

However, as of Thursday, 8000 public hospital beds are already occupied, a fifth of them - 1600 - by COVID-19 patients.

It is a similar story in the ICU, where about 1000 beds are available. About half - 467 - are already taken, 134 by COVID patients.

But Premier Dominic Perrottet said the modelling is encouraging, as it demonstrates the state's health system will cope.

"Even on a worst case scenario, we have the capacity in our health system right now," he said.

"We are seeing significant pressure on our health system, but (it) is strong."

Still, Mr Perrottet announced non-urgent elective surgery will be suspended until mid-February, as was done in response to thhe Alpha and Delta outbreaks

However the concern is not necessarily the amount of beds the state has available, but whether there it has enough staff.

With the number of infections in NSW dwarfing previous outbreaks, scores of healthcare workers have been furloughed with the virus.

The government a week ago changed isolation guidelines for them in an effort to stem shortages.

Health staff "essential to service delivery" who are household contacts can now return to work after just seven days, while those exposed in a "social setting" are able to return to work in two if they get a negative test result.

Ms Pearce said staffing challenges had been factored into the health system capacity modelling.

"We obviously consider very carefully our workforce and ... we revised down quite significantly the number of ICU beds available, for example," she said.

But NSW Health is still calling out for everyone who is a registered health professional and may be able to assist to roll up their sleeves.

"If I need to put on a uniform myself and go and work, I will," Ms Pearce said.

Australian Associated Press