Boxes with dry ice and GPS tracking mean the first Covid-19 vaccines to arrive in New Zealand could conceivably be given in GP clinics and rest homes.
A special Government taskforce will ultimately decide who is prioritised and how, with more details set to be announced.
The Pfizer-BioNTech vaccine is being used in countries including the United Kingdom and United States, and could be here from about March.
New Zealand has bought enough for 750,000 people. The Pfizer vaccine needs two doses and to be stored at about -70C.
That will make distribution complicated, but Dr Kate Baddock, chairwoman of the NZ Medical Association, said the experience in the UK showed the whole of New Zealand could be covered.
The government has ordered nine large super-cold freezers, and 40 smaller ones. From there, distribution can be done with boxes filled with dry ice, which can keep hundreds of doses at the required temperature for days.
Once removed, vials could be kept in a normal fridge for days longer, Baddock said, and when out of the fridge had to be used within about six hours.
"Certainly, it will be possible for it to be delivered through general practice. It may not be all practices can do it, it will probably be the bigger ones that will have the capacity to hold the vaccine, have a regular supply chain and can maintain all the requirements."
However, Dr Bryan Betty, medical director for the College of General Practitioners, said much would depend on who was prioritised, and the initial tranche of 750,000 doses might be largely delivered through more central distribution points, rather than GP practices.
"I think it's going to be quite limited in terms of where that vaccination goes and how it's given. However, as more vaccination becomes available, absolutely general practice would probably be involved."
The UK was the first country to approve the Pfizer vaccine for emergency use, and approval is looming for a second vaccine, developed by Moderna.
Australians were also set to get their first Pfizer vaccines in March, but Prime Minister Scott Morrison now says that could happen, "a bit earlier".
National's Covid-19 response spokesman Chris Bishop yesterday took aim at the Government, saying it should have told Kiwis what vaccines were coming, and when, how quickly they could be available to everyone, and when the country might reopen.
Different scenarios are being considered, including if there's a community outbreak when the vaccine rollout starts. Those prioritised are likely to be those most at risk, like border and healthcare workers, and people at risk of spreading the disease or of serious illness.
Simon Wallace, chief executive of the Aged Care Association, which represents most aged-care organisations and companies, said the roughly 35,000 aged care residents and 30,000 workers should be prioritised.
"That has been taken on board by the ministry. I would hope they follow the lead of the UK, who have prioritised care home residents and over 80s as being the top priority group for rollout of the vaccine."
The association's preference is for registered nurses working in aged care to administer the vaccines at rest homes, as they were already known to vulnerable residents, some of whom shouldn't be moved.
"What has been very difficult over the last nine months now has been the fact that we've had to close down our facilities to visitors. So this will be a huge breakthrough ... we can eventually return to some sort of normalcy."
New Zealand also has another vaccine agreement with Johnson & Johnson's Janssen Pharmaceutica, to get up to 2 million doses from the third quarter of 2021. The vaccine is single dose and easier to store.
More agreements are expected - $66m has been set aside for the Covid-19 immunisation programme, which has a governance group featuring experts including Mainfreight founder Bruce Plested and IT expert and former Deloitte chairman Murray Jack.
In July the Government announced $23m to replace the "not fit for purpose" National Immunisation Register, in anticipation of the Covid vaccination regime and after last year's measles outbreak.
GPs told the Herald they were ideally placed to help monitor who needed immunisation.
"We have delivered millions upon millions of doses of vaccines, across all the age group spectrums," said Dr Tim Malloy of the General Practice Owners Association (GenPro).
"We have IT systems that allow us to identify those patients who have greatest need."
That view was echoed by the College of General Practitioners, and NZ Medical Association chairwoman Dr Kate Baddock, who noted the warning out of the UK for people with a history of significant allergic reactions to not receive the vaccine.
"Initially, we thought [Covid immunisation] would lend itself quite well to drive-through clinics. But there might well be a requirement for a 15 to 20 minute observation after the vaccination."