A researcher who's mapped striking geographical disparities around vaccination says moving the country into a new traffic light system too early could put vulnerable communities at risk.
New Zealand's overall vaccination rate has now climbed to 90 per cent of the eligible population for first doses, and 81 per cent for both jabs - with Saturday's total tally of 26,996 adding to more than seven million shots administered to date.
Coverage among Māori - at 76 per cent for first doses and 60 per cent for both – however continued to lag behind the national average.
Respective rates for Pacific people, at 88 and 76 per cent, were higher but also trailed the overall figures.
When he delved deeper into the data and looked at the picture at suburb-level, Waikato University research fellow Dr Jesse Whitehead found those nationwide numbers obscured much lower coverage rates among Māori and Pacific across large pockets of the country.
That was a concern, he said, as a region that might reach an overall vaccination rate of 90 per cent – the threshold at which regions shift move to the new traffic light system – could still have low uptake among its most vulnerable people.
Total vaccination rates dates (dose one, November 9)
Total vaccination rates (dose two, November 9)
Total Māori vaccination rates (dose one, November 9)
Total Māori vaccination rates (dose two, November 9)
"I'm in Waikato – and an overall level of 90 per cent in Hamilton can make the whole region look like it's got better coverage than it does, yet in a lot of communities here, numbers may be really low."
Recent modelling by Te Pūnaha Matatini researchers has indicated 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.
Total Pacific vaccination rates (dose one, November 9)
Total Pacific vaccination rates (dose two, November 9)
Whitehead's analysis, which drew on data from HealthPoint and the Ministry of Health, also found links between low uptake and places where there was poorer accessibility to vaccination services – or longer travelling times to get to them.
For urban areas, he's found the median drive time to the nearest service was three minutes - but this more than tripled to 10 minutes for rural areas.
In the most remote areas of Aotearoa, this increased again to a median time of 21 minutes.
Work he's carried out with Otago University researchers showed that, as of a month ago, the rate of rural Māori with at least one dose was 10 per cent lower than urban Māori.
Many of these areas were also likely to have younger population age structures - meaning they had been eligible to receive the vaccine for a shorter period of time than other neighbourhoods.
"Especially in communities with a lot of Māori and Pacific residents, many people have only been eligible for the vaccine for a matter of weeks – while those in group one in the roll-out, or even the top end of group four, have been eligible for several months."
The Bay of Plenty town of Murupara, for instance – which has been singled out as the nation's "slowest town" - had one of the lowest levels of spatial access to vaccination services in the country.
Not only was the nearest permanent vaccination site a 50-minute drive minute drive away, but the median age of the town in 2018 was around 29 years.
Travelling times to vaccination clinics (November 9)
Other areas with low second-dose rates included rural parts of Northland – where coverage was still below 60 per cent – and the Midland region, which included Taranaki, Waikato, Lakes and Tairawhiti.
"This all means that, with more Aucklanders potentially travelling into other regions for Christmas, it could prove a nightmare for some communities, given one case in an isolated rural community can be enough to seed a new cluster."
Last week, Prime Minister Jacinda Ardern hinted the system could even be extended nationwide when Auckland moved to it – even if other regions hadn't reached 90 per cent.
Whitehead said taking more of a geographic approach to getting the vaccine to communities could improve the situation.
"Earlier this year, we published a paper showing that if we were running vaccination clinics from every school in the country, 99.9 per cent of the population would be within a 30-minute drive," he said.
"This isn't the only factor in low coverage, but it's one possible solution going forward.
"We can also see from our maps that areas with high at-risk populations also haven't been targeted with extra services.
"Experts in Māori and Pacific health have been talking about giving resources to these communities to run their own vaccine roll-out in a way they know works. I think that would be really helpful as well."
Those points have also been sounded by Otago University health researcher Associate Professor Garry Nixon.
"In many overseas countries rural communities have ended up with more Covid‑19 and higher death rates than the cities, and still are because of lower vaccination rates," he said last month.
"Rural areas are no place to come down with a serious respiratory illness that needs intensive care. We don't have to go there, but it's crucial that every rural Kiwi who's eligible gets vaccinated, and gets vaccinated now.
"This is further evidence that a concerted effort needs to be made to improve access to vaccination for Māori communities, including those outside the major centres."
Immunisation Advisory Centre director Dr Nikki Turner agreed that a mixed, targeted approach was needed to get the vaccine to those low-coverage areas.
"Vaccine mandates only take you a percentage of the way there - but really well delivered health services take you a long way," she said.
"So, it's really about looking to those communities that have lower coverage, and then focusing your health services on those who are continuing to miss out."