Māori health experts say they are being left in the dark over data collection to track the impact of Covid-19 on vulnerable communities.
Māori overall die about seven years earlier than non-Māori, and are also more susceptible to a range of diseases, meaning they are more likely to contract and less likely to recover from Covid-19.
These factors are compounded in rural areas with poor access to healthcare.
The Government's Covid-19 modelling assumes Māori hospitalisation rates from Covid-19 will be five times higher, and risk of death 2.6 times higher, than for Pākehā.
For these reasons Māori health experts say a "one size fits all" approach to data and modelling is not acceptable.
The National Māori pandemic group Te Rōpū Whakakaupapa Urutā, which consists of some of the country's top Māori health experts, has raised concerns about how exactly the spread of the disease is being tracked through Māori communities.
They believed it was "premature" for the Ministry of Health to say the "peak" of Covid-19 cases may have been reached.
"We question how the Ministry knows this is the case for Māori communities," a spokeswoman said.
"Without the accurate data and analysis, we believe it was a very unwise statement to make, particularly for Māori."
Māori communities have higher health needs, with many health conditions that make them much more susceptible to Covid-19.
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They were concerned as they did not know the source and quality of the data being collected, how ethnicity data was being collected when Māori were seeking testing or being referred for testing, and that there was no nationally consistent approach to ethnicity data collection.
"This means that we don't have a complete picture of what is happening in Māori communities or an understanding of the likely and predicted footprint of Covid-19 into Māori communities."
Due to the specific health concerns of Māori and lack of data collection, a "peak" in the number of cases overall might not mean the same for Māori.
"Without that knowledge, we aren't able to front-foot a tailored and specific Māori response for communities who need it."
University of Auckland statistician Andrew Sporle said the lack of transparency and sharing of data was a "major issue".
"In past pandemics there has been a vast impact on Māori," said Sporle, deputy director of the Healthier Lives National Science Challenge.
"In the 1918 flu Māori died at seven times the rate of non-Māori. My grandma told horrific stories of that time, when there were not enough people to move all the bodies. And even in recent times with the 2009 swine flu the rate was 2.6.
"There shouldn't be that discrepancy. We are talking about a potentially huge amount of preventable deaths, and we cannot address that if we do not have access to good information."
The information they were after included anonymised lists of who had been tested and who had been positive, with factors such as ethnicity and gender, along with general age and location.
For example, as Māori had a lower life expectancy, those in the over 60s should be treated as if they are over 70.
"We have no idea the age of Māori being tested, if they are being turned away when really, because of those differences, they should be classed as high risk."
With that information, Māori data experts could not only help with tracking progress of the disease in the community, but quickly jump into contact tracing and prevention in case of an outbreak.
"For example people living in those communities will know where areas of high-density housing are, where they might be a lot of people living in a household compared to others.
"It is a combination of having that fine-grain information and contextual knowledge, which is what these Māori health providers have."
Due to the lack of information, iwi health organisations had started doing their own testing and community mapping, he said.
If the eradication goal of Covid-19 fails, a Ministry of Health report has recommended "safe havens" be established across the country for vulnerable populations, including Māori.
Sporle says the checkpoints set up by iwi in absence of action by local authorities were essentially pre-empting those safe havens.
"Māori recognise this 'one size fits all' approach does not work - and it never has, and it is no surprise we are seeing community checkpoints popping up.
"Two weeks in and nobody can tell us where the Māori cases are. We cannot sit and wait for Wellington."
Sporle said he and all Māori health specialists he knew had offered their time and assistance to the Ministry.
"There are a lot of people offering help - we cannot wait."
The Ministry of Health has been approached for comment.
Deputy Director-General Māori health John Whaanga told Newshub this week there had been a "real drive" to increase testing across the country, and collecting accurate ethnicity data for Māori was a key part of this.
Of the country's 1239 Covid-19 cases, about eight per cent are Māori, although the proportion has been gradually increasing.