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New Zealand is projected to reach the symbolic 90 per cent vaccination milestone among eligible Kiwis by Christmas – the goal of a long-running Herald campaign.
The Herald's vaccination tracker is already forecasting a double-dose rate of 90 per cent by Christmas Eve – and it's hoped ongoing hard work by health workers, and motivation from the arrival of vaccination passes and eased restrictions, will prove more than enough to get there.
On Friday, health authorities confirmed that 90 per cent of the eligible population across Auckland is now fully vaccinated.
As of yesterday, some 3.6 million eligible Kiwis (88 per cent) were now fully vaccinated, while 3.9m people (93 per cent) had received at least one dose.
That left some 285,244 people – or 6.8 per cent of the eligible population – completely unvaccinated.
Just four district health boards – Auckland, Waitematā, Capital and Coast, and Canterbury – have reached the 90 per cent double-dose threshold, although several DHBs, including Southern (88 per cent) and Counties Manukau (87.2 per cent), are closing in.
Such percentages sometimes didn't give a clear picture of just how many vaccinations were required to hit 90 per cent. For instance, the West Coast was sitting at 81.5 per cent double-dose coverage, but needed only 2,371 more vaccinations to reach 90 per cent, while the Bay of Plenty, at 82.9 per cent, needed more than 15,300.
Auckland holiday travel: Potential for 'real disaster'
Epidemiologist Professor Michael Baker says we need to make summer as safe as possible; particularly as Aucklanders get set to leave the city that is still dealing with Covid-19 in the community.
Baker told TVNZ's Breakfast that despite vaccination rates now being very high in the Auckland region, we will still "probably" see more transmission of the virus in the city.
"This is uncharted territory at the moment. We've had 18 months with the very effective alert level system ... and this is a whole new world."
A lot more responsibility now rested with individuals, he said.
On people moving out of Auckland over the Christmas period, Baker encouraged people to get tested beforehand - even children.
"If there are children in the household, get at least one of them tested before heading away. Because if there is Covid in the household, it is likely young children who are not eligible for vaccinations will have contracted the virus at that point."
He also said it was best to have conversations with family and friends outside of the city they are due to visit, to ensure they are vaccinated.
Baker said "make alternative plans" if family members remain unvaccinated. He acknowledged that these are extraordinary times and those precautions should still be made to protect older members in the family, or family and friends who have other health conditions or are immunocompromised.
"They are very vulnerable to get this infection. It won't happen every time, but it will happen often enough that we could see some real tragedies around the country."
Asked if he was concerned as Aucklanders would officially be allowed to leave the city from next week, he said he is.
"Really, I don't think anyone from Auckland should go and stay with unvaccinated people. I think that could be a real disaster."
Experts have also cautioned the 90 per cent target masked still-lagging rates among vulnerable populations such as Māori and Pasifika – and also didn't account for the risk faced by children, who won't be eligible until next month.
University of Auckland epidemiologist and data scientist Dr Janine Paynter said she was more optimistic about the forecast for vaccinations than tracking tools like the Herald's suggested.
"It's important to look at what's happened in the last two weeks or so as the change to the traffic light system became imminent," she said.
"There was an uptick in [the] numbers of vaccinations. I speculate that people are likely to bump vaccination briefly up their priority list before they get wrapped in holidays or maybe make getting a vaccination once they are on holiday a priority."
She said another positive was that only non-Māori, non-Pacific eligible uptake seemed to have plateaued at around the 90 to 95 per cent mark, depending on the particular area.
"We're probably reaching the proportion, for this subgroup of people, who will strongly resist vaccination – I say this because it's consistent with the proportion who decline childhood immunisations."
Currently, around 71 per cent of eligible Māori were fully vaccinated, while 84 per cent had received their first dose – with respective rates for Pasifika people sitting at 82 and 91 per cent.
"Uptake of first doses has slowed a little for Māori in some DHBs, but it's not plateauing and where it is plateauing for the Pacific population the coverage is approaching 90 per cent," Paynter said.
"It's not slowing for the younger population either."
Paynter said it was important that this momentum was maintained.
"It's been said before, but these groups should have been prioritised sooner so that we could have had this momentum earlier."
Māori were two-and-a-half times more likely to need hospital care for Covid-19 than non-Māori - while the risk for Pacific people was even greater, at three times higher.
Among other inequity issues with the roll-out, researchers note these populations have younger age structures – and thus many had been eligible to receive the vaccine for a shorter period of time.
"We're in a catch-up mode," Māori health researcher Dr Rawiri Taonui said.
With Māori making up a disproportionate number of Covid-19 cases to date - and with many rural communities with large Māori populations still reporting worryingly low coverage – Taonui feared Auckland's re-opening could come with a high toll.
He also worried the Ministry of Health's dataset may be underestimating the number of Māori still to be vaccinated.
Compared with the ministry's 88 per cent of 4.21 million eligible Kiwis fully vaccinated, the most recent Statistics New Zealand estimates suggested just over 84.5 per cent of an eligible 4.36 million had received both doses.
Taonui said his calculations indicated an undercount of around 45,000 among Māori.
On top of that, he pointed out around 70,000 people who identified as Māori in Census-based population estimates weren't recorded as such in the ministry's internal database.
He said a targeted approach was urgently needed.
"DHBs need more resourcing from Government – but they also need to be supporting Māori health providers and giving them what they need to get to those under-vaccinated areas."
Modelling shows the difference that 90 per cent coverage – initially a benchmark of the new traffic light system – can have at slowing the spread of Covid-19.
If there were 10,000 exposures of Covid-19 in a population with just 50 per cent coverage, for instance, the result could be 2875 cases and 263 hospitalisations – with all but 13 of those hospital cases being unvaccinated.
At 90 per cent, however, those 10,000 exposures would result only in 1175 cases and 73 hospitalisations.
How high could we ultimately push coverage?
University of Auckland vaccinologist Associate Professor Helen Petousis-Harris saw potential to lift national rates to 95 per cent, among the currently eligible.
That was because there were still a large number of people who hadn't been able to access the vaccine, she said, or who weren't against vaccination but had some unanswered questions.
"That's going to take some hard work – but I think it's fair to say that it's doable."
Professor Peter McIntyre, of the Immunisation Advisory Centre, said the final five to 10 per cent of a population were tough to get on board in any vaccine campaign.
And given the Pfizer roll-out marked New Zealand's biggest vaccine drive ever – and the first time that everyone over the age of 12 has been approached – this challenge was even tougher.
"Community health providers around the country are trying to reach as many people as possible and are doing great work," he said.
"It is the community providers who know best what their communities might need to encourage them to get vaccinated."
McIntyre said the introduction of boosters and child vaccines would make a big difference to New Zealand's collective protection.
"There is a very low risk of severe disease among children aged 5 to 11, but they can still get sick," he said.
"The main community benefit of them being vaccinated is that it reduces infections overall.
"On the other hand, we know that those most at risk of severe disease - elderly, those with other significant health problems and especially compromised immunity also have the weakest vaccine response and really need that extra level of protection."
How long till each DHB reaches 90%?
As more people become vaccinated, there will be fewer and fewer people who are eligible for vaccinations. Reaching and convincing the remaining people will become harder, slowing down the rate of vaccinations the further we go. An estimate that doesn't account for this slow-down will constantly underestimate how far there is to go.
Using vaccination data from the Ministry of Health, we've created a simple statistical model for vaccination rates in the next four weeks.