Covid-19 vaccination uptake among Māori is only about two-thirds that of the general population.
The latest vaccine data shows in the Bay of Plenty, Lakes, Northland and Taranaki DHBs fewer than half of Māori have even had a first dose.
The government has consistently defended its approach to the vaccine rollout, saying Māori are younger and will therefore lag in vaccination rates.
But critics have repeatedly said Māori should have been prioritised for vaccination and the roll out was too Anglo-centric.
It has been a month since all New Zealanders over 12 became eligible for the vaccine and only 55 percent of Māori have had their first dose.
Te Rōpū Whakakaupapa Urutā co-leader Rawiri Jansen said he had seen some improvement, but there was more to be done.
"There is some improvement for Māori in terms of accessing vaccine and it does show up quite good in Auckland, where it's predictable with the Delta outbreak there's been a huge surge in accessing vaccine. But it's right to notice that other parts of the country haven't been able to reach Māori communities in ways that we would have hoped for and, I think, we're going to need."
There had been an increase in some of the features of the rollout Māori leaders had been calling for, such as education campaigns and events which resonated with Māori, but there needed to be more of it, Dr Jansen said.
"It's an enduring pity that wasn't the feature that we saw right at the start of the campaign, but I'm confident that if we keep doing enough of that we'll end up with a really great result."
The pandemic had exposed features of the health system which benefited the majority rather than bending towards equity, he said.
Addressing those historic policies and inequities would be key to not only protecting Māori and Pasifika from the worst effects of the pandemic, but ensuring equity in the health system in future, Dr Jansen said.
"I'm concerned that an outbreak in under-vaccinated Māori could be catastrophic," he said.
"So I really endorse mainstream New Zealand accepting that it will take three or four or five extra weeks to get the Māori population into the right place with respect to protection from Covid by being vaccinated. That's in all our interests to do that - having mass outbreaks of Covid will affect the health system for everybody. So it's in our interest to make sure that we have a vaccination programme that reaches 95 percent of Māori."
Based on current vaccination rates when 90 percent of the general population was fully vaccinated, only 62 percent of Māori would be- potentially 200,000-plus eligible Māori without a vaccine, which did not include the population under 12.
"That's a huge number of unvaccinated Māori and that's a huge reservoir for an outbreak that will swamp our hospital system, now nobody should be calling for that to happen. We've got to get this job done," Jansen said.
Modelling suggested a Covid outbreak among an under-vaccinated population https://www.rnz.co.nz/news/national/452127/covid-19-modelling-90-percent-vaccination-needed-to-avoid-lockdowns could be devastating], and Māori are more vulnerable to the virus.
Research from Te Pūnaha Matatini showed a 44-year-old Māori person was at the same risk from Covid-19 as a 65-year-old Pākehā.
Jansen said the longer people were unvaccinated the more time antivax conspiracy had to reach them.
"One of the things is because Māori weren't prioritised early in the vaccination rollout they've actually been exposed to much more antivax or vax hesitant messaging for a much longer period of time - that shouldn't have happened. We could've done this differently but it has happened, now we've got to do extra work to get to the right place."
Bringing the vaccine rollout into workplaces, religious spaces, marae and schools would provide an opportunity for that kind of antivax messaging to be overcome as people saw their peers and community receiving the vaccine safely around them, he said.
Medsafe was expected to assess evidence this month on whether the vaccine could be rolled out to 5-12-year-olds.
"The government should be preparing a programme for school vaccinations at the earliest opportunity because that's the best way of getting Māori vaccinations up to the levels that will protect our community.
"In saying the government - it's really the Ministry of Health, it's the Covid division within the ministry and it's all of the DHBs and all of the services that wrap around schools. So that's a big piece of work, but that's really worthy of our attention because it will get a good outcome for the country and it will get a good outcome for the Māori community."