A vaccination rate of nine out of every 10 eligible New Zealanders is a great headline number. But it can also be deceptive. The Spinoff’s head of data Harkanwal Singh explains.
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Today the Spinoff is adding new graphs to our Covid tracker. They’re designed to highlight the challenges that become visible when we look beyond one number.
We’ve heard a lot about 90% lately: from Ashley Bloomfield, from experts and from media. Modelling from Te Pūnaha Matatini published yesterday shows that to control the virus New Zealand needs to lift rates well over 90%.
But beyond that headline number lie other challenges. The vaccination data in the graphs below are broken down by ethnicity and age at the DHB level.
It reveals startling gaps at local levels. For example, while Auckland may reach 90% overall, the picture will look different for different communities.
In Auckland Metro DHBs (Auckland District, Counties Manukau and Waitematā), the vaccination rates vary widely depending on the age group and ethnicity. Each dot shows the vaccination rate for a group by ethnicity and age.
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The younger Pasifika population is getting vaccinated more quickly than Māori in Auckland Metro DHBs. You can click on the legend to hide/show data for different ethnicities for easier comparisons.
The gap widens in Waikato and the numbers are even lower. For the older population at DHB levels, the data is noisy as a higher percentage number hides the fact that Māori population numbers are smaller in those age groups because of lower life expectancy.
The more challenging story is revealed when we look at vaccination rates by the first dose.
This graph shows all age groups in all DHBs – the number for Māori youth is lowest across all. It is easier to understand this graph by focussing on colour. The gap between Māori and Asian populations is wide for younger age groups across all DHBs.
The following graph shows the proportion of the population which has received the first dose in Auckland Metro DHBs.
The shape tells the story. We need everyone to try and go beyond 90%.
The 90% number is a compelling sell and has an appealing simplicity, but getting all subpopulations vaccinated is critical to controlling Covid.
Auckland University statistician Thomas Lumley says the subpopulations will be more socially connected on average than the whole population is on average.
“Low vaccination rates can give you a sustained epidemic even if the population as a whole looks safely vaccinated. This would be just as true if the subpopulation was soccer moms or dog owners or whoever.”
Māori and Pasifika health experts have been warning about failures in prioritising vaccination for Māori under the age of 65.
Māori and Pasifika have large proportions of their population in the younger age bands. The graph below shows the population distribution by age group.
A recent Spinoff article by Dr Rawiri Jansen summarises a study published in the New Zealand Medical Journal which delves into detail on what the gaps shown in the charts on this page mean for these communities and Aotearoa.
The shape on these charts will need to improve and that’s why you will be able to find them on The Spinoff Covid tracker, updated every Wednesday when the Ministry of Health releases new data.
The charts on the tracker page will open on the national averages shown below. You can select from the dropdown and see data for your DHB.
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