There are two main messages for New Zealanders in the report on whether and how the country can reopen to the world, the public health experts who wrote it say.
A new report - with the backing of public health experts - is calling for a phased reopening of New Zealand's borders, but only once the vaccination programme is fully rolled out.
But the report written by the Covid-19 health advisory group for the government warns there will be further outbreaks to come.
The group suggests with high vaccination rates, a phased approach to resuming international travel is possible.
That could mean a shorter stay in managed isolation and even home quarantine, if testing and contact tracing systems are cranked up.
University of Auckland physics professor and Covid-19 modeller Shaun Hendy, who was part of the advisory group which authored the report, told First Up "For most of us the fact that we're not going to see significant re-opening of the borders until the vaccination program is complete, I think that's probably the big message".
"But then I think the second point that people should be aware of is there's still huge uncertainty at the moment and there is still a significant risk that we may see a new variant that's even more transmissible than Delta that really puts these plans on hold and forces us to rethink what we do at the border."
Hendy said people needed to be aware that the situation is very fluid.
"I think it's obvious we'll be seeing outbreaks in certain parts of the world for some time yet. The vaccination program has as well advanced in Europe and the United States but less so in other parts of the world, so you know that might be possible for - in low risk parts of the world where vaccination programs have brought the virus under control - we could certainly look for people who have been vaccinated, you know, to reduce restrictions - once everybody here has had a chance to be protected.
"I think that's the important point, that it's not zero risk when someone travels overseas even to a country worth low prevalence, even if they've been vaccinated. And it's important that the population here is protected as much as we can for the chance of the disease coming back into the country."
On vaccination rates, Hendy said for herd immunity and the outbreak to die out on its own, about 97 percent of the population would have to be immunised.
"We think that's probably an unlikely target, so we do need to aim very, very high. And even then, if we have another variant or variant that's more transmissible or evades the vaccine, then that number would be much higher.
"So having a target short of 100 percent is not going to give us any sort of extra confidence."
Professor Sir David Skegg led the group, and told Morning Report:
"We really need to get as close as possible to 100 percent [vaccination rate]. They're saying, you know, 70-80 [that] almost encourages underachievement and you know, would not be optimal.
As for travel conditions, Skegg said: "Travellers will be classified according to, first of all, that they should be vaccinated. Which country they're coming from. There'll be preflight testing."
"They'll be tested at the airport when they arrive, so some people will have to go into MIQ, but other people will have a reduced requirement or have quarantine free entry and can come straight away, but it will be important that we do have ways of checking on those people and also that we all need to increase our public health and social measures so that the country can continue to stamp out the infection.
"I'm hoping that people from lots of countries who've been fully vaccinated, who've been tested at the airport at could avoid MIQ. That's certainly the advice of our group that we should be aiming at."
"Unless the whole community supports this we're going to end up like most other countries in the world" - Sir David Skegg
"There will be countries where people will still need to have 14 days isolation or quarantine, but there'll be other countries where the risk is judged to be lower.
"Countries that are managing Covid-19 well where we can really trust the information about the pre-flight testing. There will definitely be different layers, and it's going to be more complicated, but I think that's the way it's going to be in the future.
As for those hoping to travel without being vaccinated, Skegg said: "I don't think many airlines are going to be accepting people who haven't been vaccinated in the future.
"That's clearly the message that's sort of coming out... So I think vaccination will be a prerequisite for international travel. That won't just be in New Zealand requirement. I think it will be worldwide.
"We've specifically suggested that children who are not eligible for vaccination would not require to be vaccinated if they're travelling with their family. Obviously, depending on the age for eligibility that would influence that."
It was possible that a plan to re-open borders could be derailed if another variant appeared, but Skegg didn't think it was likely with the Pfizer vaccine available.
"We're very lucky these MRNA vaccines so far have held up well against all the variants that have arisen.
"But it is a possibility and it's yet another reason why we should, we believe, maintain our elimination strategy, trying to stamp out this infection as it occurs because obviously if a severe variant that could evade vaccine immunity turns up, we'll be changing our policy and would be very glad to have kicked it out."
The group did not suggest any vaccination rate targets in their report.
"It doesn't mean eradication. It doesn't necessarily mean zero Covid. What it means is zero tolerance towards new infections so that as they arise they are quickly stamped out.
"This is what we do with measles. New Zealand has eliminated measles. It's endemic in many countries, but it's not endemic here and we maintain it - it keeps coming across the border, but because we've got a really high vaccination coverage and because we use public health measures, we manage to keep measles from being endemic in this country.
Re-opening the borders would require us to "do quite a lot of things in the next six months", Skegg said.
"We believe that the public health units need to be strengthened so they've got more capacity for contact tracing. Look what's happening in Sydney.
"We also need to lift our game generally, I mean, people aren't scanning QR codes very consistently. People don't go and get tested when they have cold or flu symptoms.
"Unless the whole community supports this we're going to end up like most other countries in the world."
Public health expert professor Michael Baker was not part of the group but said the cautious approach advised in the report was "absolutely" the right one.
"All the evidence we have is that the elimination approach has performed very well compared with the rest of the world, both in terms of protecting public health and also protecting our economy. And in addition, it's allowed normal life to return more in New Zealand than in other countries across the globe."
Asked what a "fully rolled out vaccination program" would look like, he said
"I think the main requirement is as high vaccine coverage. The report didn't set a goal, which I think is reasonable because it's as high as possible, and that's because we know from the modelling that even with 100 percent coverage, which we won't achieve, there's still potential for the more infectious variants to spread.
"And that's because no vaccine is 100 percent effective at stopping transmission."
Complete rollout would be hard to define, Baker said.
"I think it will be a sensible compromise that when we get to the stage where you're running mass clinics, our vaccine is readily available and people are no longer turning up and the evidence is that you've got high coverage - hopefully the late 80s, maybe even above 90 percent coverage. At that point, people have decided that they're going to get vaccinated or not.
"It is challenging, but I think there will be a point when we can say we've reached maximum coverage that we're going to achieve. There will still be people who will drift in, but really the curve is flattening out and I think that will be fairly apparent from the data."
There was an argument for having a vaccine target, but a problem was that we could not "vaccinate our way out of this", Baker said.