Immunisation rates of babies in Tairāwhiti have dropped "disturbingly low", with one expert saying it reflects an overstretched health system in the middle of the Covid-19 vaccine roll-out.
Hauora Tairāwhiti District Health Board figures show a five percentage point decrease in infants being vaccinated at eight months from April to May.
It has prompted a "reset" in Hauora Tairāwhiti's approach to immunisations and an urgent meeting with iwi and Māori health providers.
Immunisation Advisory Centre director Nikki Turner said similar patterns were being seen across the country.
"The challenge with families and getting infant immunisations, is getting into services on time, particularly for families from high deprivation (areas)," she said.
When health services were "squeezed", children from backgrounds of deprivation and poverty were the first to miss out.
"When our services aren't over-busy and aren't stretched, it works a lot better.
"The other problem that we're seeing is the health sector is pulled in so many directions at the moment with the Covid-19 vaccination programme.
"It's a hard environment out there, so this is really recognising that our families are finding it hard, and our health sector is finding it hard."
Figures for May show 82 percent of all babies in Tairāwhiti and 76 percent of Māori infants were fully immunised at eight months.
The rate of immunisation at two years old was 79 percent overall and 76 percent among Māori.
The government's target is 95 percent.
Hauora Tairāwhiti chief executive Jim Green said the rates were "disturbingly low" and "urgent action" was needed to work out what more could be done.
Green last week told Hauora Tairāwhiti board members that they had been making "good progress", but the decrease in May was "concerning".
"We've had some correspondence from the Ministry (of Health) in general about immunisation rates and ensuring that we are applying attention to those, which of course we are."
Green said they must not lose sight of vaccinating mokopuna amid the Covid-19 vaccine rollout.
"That is certainly on the radar for us and for the ministry," he said.
Hauora Tairāwhiti group manager planning, funding and population health Nicola Ehau said they could speculate as to what had caused the decrease, but needed more in-depth analysis to be clear as to why.
Hauora Tairāwhiti was establishing a specific programme that focused on childhood immunisation in the 2021-22 year.
They were also resetting the local steering group to enable better-coordinated sharing of information and activities that could then be scaled up if improvements that could be replicated were seen.
The current approach had relied on a "traditional response" that had been proven not to work.
"We are looking to flesh out what this reset will look like including working with our key iwi/ Māori providers. This needs to happen before we can add substance to a planned direction."
An urgent meeting had been scheduled.
In October 2020, a report to the health board said misinformation and rumours about vaccinations, along with hesitation about visiting medical practices following the Covid-19 pandemic were affecting the region's immunisation rates.
At that time, immunisation rates were 79 percent at eight months and 86 percent at two years.
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