The New Zealand Nurses Organisation (NZNO) says it's concerned staffing levels at hospitals in the Auckland metro DHBs are putting patient care at risk.

But Deputy Prime Minister Grant Robertson is adamant that the health system is not overly stretched, while a senior Ministry of Health official says the system is also coping.

NZNO lead organiser Christina Couling says while the Government and the DHBs report they have enough beds, that isn't a lot of use when there aren't sufficient staff to look after the people in those beds.

"The strain on Auckland health care workers right now is enormous. Each of the three Auckland DHBs has 300 to 400 nursing vacancies at present and, on top of this, members say a lot of staff are taking sick leave, which puts even more pressure on those remaining at work.

"Auckland hospitals may be at less than 100 per cent bed capacity, but in many cases, there are not enough staff to provide the care required for patients who are seriously unwell with quite complex needs.

She said the health workforce was under considerable stress across the country but the situation was especially dire in the Auckland region which had increased demands.

"We are seeing nurses not coming into work because they are overwhelmed and stressed. Stand-downs relating to Covid exposures events also create additional pressure. This is only going to get worse if they continue to be unsupported."

Robertson and director of public health Dr Caroline McElnay provided an update on the Covid-19 Delta outbreak at 1pm today.

Robertson denied the system was overwhelmed.

He said the health system was set up to make sure it did early assessments of whether people were safe to isolate at Covid at home. He said a standardised approach might not work for everyone in the community and that was why an individual assessment was needed.

On the nurses' association speaking of severe staffing shortages, Dr McElnay said she based her comment on the health system being able to cope with rising Covid numbers on her conversations with the heads of the DHBs.

ICU occupancy is around 70 per cent, and ventilator capacity is at 15 per cent.

"We can manage, but it is important that we limit the loads on our hospitals," she said.

McElnay said there were constant meetings across DHBs to ensure they continued to learn how to deliver better care.

"People have died this week and that is tragic for their friends and family. It is a sad reminder that Covid is potentially fatal, and this is particularly true if you are unvaccinated," she said.

There are currently 81 people in hospital with Covid, including 11 in ICU. A total of 51 of those in hospital had not been vaccinated, 20 have had one dose of the Pfizer jab, while one has had two doses, but the second dose had been given to them less than 14 days ago.

A further five fully vaccinated people who have been diagnosed with Covid are also in hospital.