Hospitals are planning how to cope when Covid becomes endemic in New Zealand and the unvaccinated turn up seriously sick.
Sarah Dalton, executive director of the Association of Salaried Medical Specialists union, told the Herald discussions were taking place among DHB leaders.
"We may be moving into a phase of what the DHBs are calling endemic Covid - even if we manage a form of elimination this time, as soon as the borders reopen, we will have Covid come back.
"It is going to be a massive challenge."
Covid-19 becoming endemic means the virus won't disappear even with high vaccination rates, but will instead regularly circulate in the population for months and years to come, possibly flaring up into significant outbreaks.
The high transmissibility of the Delta strain means the unvaccinated minority are most vulnerable, including to serious illness and hospitalisation.
Treating infectious and potentially infectious patients is resource intensive, with staff needing to obey strict protocols and put on and remove PPE. Different areas of hospitals would be needed for Covid patients.
A senior specialist at an Auckland hospital told the Herald how the health system would be affected by endemic Covid cases was a major concern for frontline workers.
"We will have to keep hospital resources available to treat a steady number of endemic Covid cases. No doubt about this. This is just how Delta works in a population where the vaccination rate is less than 100 per cent.
"We need extra manpower and extra time to cope with the fitting and removing of PPE for Covid cases. Doing surgery on a Covid case is very time consuming. Some nurses are not yet vaccinated and this may cause difficulties in work allocation."
The system was already under stress, he said, so dealing with endemic Covid cases would have a knock-on effect and lead to delays in treatment for non-Covid patients.
Another current focus is the huge number of people who have had their planned care put off or delayed to some extent because of the current lockdown even including some cancer cases, he said.
DHBs often look to send patients to private facilities to help cope with demand, but private hospitals will need to work through their own patient backlogs.
Health Minister Andrew Little has previously told the Herald that a "front and centre" consideration in loosening border restrictions will be the burden the unvaccinated would put on the health system, should Delta or future variants circulate. It will be difficult to boost capacity in the medium-term, he said.
"We have got a ways to go to improve facilities, to fill a lot of the vacancies that are in the workforce at the moment."