The changes meant the smaller Greenlane Hospital would be running very few services, with some staff redeployed to the larger Auckland City Hospital.
From today, at Auckland Hospital only the two most urgent categories of planned surgery, known as P1 and P2, will be carried out - for example, for cancers that need to be immediately removed.
Eye surgery will continue at Greenlane because that is where most of the equipment is, but from Thursday almost all other surgery there will be called off, apart from a small number of gynaecology and dental surgeries this week.
Acute surgery will continue. That is work that cannot wait, such as on people who have been in a car crash or have become sick suddenly and cannot wait.
The DHB said nursing shortages were a factor in the decision but it "would not be accurate to directly attribute planned care changes to the ... shortage."
The director of provider services, Mike Shepherd, said with a large number of Covid-19 cases in the community, it was not unexpected to see an increasing number of the hospital's staff off work because of the virus.
The decision had been a long time in the planning and there were daily meetings to discuss how to manage Covid-19 across the Auckland region, Dr Shepherd said.
He urged patients to still come to their appointments unless they were contacted by the DHB to rearrange, saying the most urgent cases would be prioritised.
"We acknowledge and apologise for the disruption and uncertainty this may cause our patients and whānau and thank them for their support and understanding whilst we respond to the on-going Covid-19 outbreak," Dr Shepherd said.
Planned surgeries, which used to be known as elective surgeries, were regularly delayed or cut through the Covid-19 lockdowns.
Hospitals and health authorities previously said that was how they would cope if hospitals had too many Covid-19 cases to carry out their normal work in this Omicron outbreak.
There were 47 people with Covid-19 in Auckland City Hospital yesterday.
The two hospitals catered for eastern and central Auckland. Greenlane was much smaller and mainly used for outpatient services, and day or short-stay surgeries.
- RNZ