Top doctor Caroline McElnay says 'no' to vaccination doesn't always mean 'never'

• The government's immunisation target still "possible", a public health official says.
• 'Declines' sometimes just need more time.
• Trust in government is lower, so supporting local health providers is key to boosting coverage.

The high-profile public health doctor stepping down as head of the country's immunisation programmes believes the government's target is achievable - but only if health providers can gain the trust of vaccine-sceptical parents.

A decade ago, New Zealand's childhood immunisation rates were the envy of the world, with 93 percent of all children fully-vaccinated by the age of two.

Rates among Pacific children were 97 percent, and Māori tamariki were level-pegging with Pākehā on 92 percent.

After falling off a cliff since then, overall rates are inching back towards 80 percent - but some experts warn the growing number of 'declines' makes the government's 2030 target of 95 percent coverage a mathematical impossibility.

The outgoing clinical lead for immunisation at the National Public Health Service, Dr Caroline McElnay, reckoned it was possible, although she would not be here to see it.

After just seven months in the role, she is off to Australia to take up the position of Victoria's Chief Health Officer.

Speaking to RNZ on Wednesday, her last day in the job, McElnay agreed "if you don't get those declines down, you're not going to get 95 percent, that's simple mathematics".

"But we are tracking upwards in terms of our coverage."

The focus needed to be on understanding more about those declines.

"We do know already that about a third of those people who we currently call 'declines' do get vaccinated, so they're not real declines.

"We want to understand better what sits under those declines and I think by doing that piece of work we will reduce that category.

"We know historically and across the world that getting to less than 5 percent [people actively declining to be vaccinated] may not be possible. But we will do everything we can to get there."

Back in 2014, she was working in Hawke's Bay, which had the highest immunisation coverage of any region at the time.

"We actually got to 97 percent, and we were equitable across the board. It's been dropping since then, but we know the system is able to offer vaccinations to everyone, we just need to get back to the point where everyone is able to get these opportunities."

Director of Public Health between 2017 and 2022, McElnay became a familiar face and voice to New Zealanders during the Covid-19 pandemic, often fronting updates alongside then-Prime Minister Jacinda Ardern and then-Director General of Health Dr Ashley Bloomfield.

Covid-19 had accelerated those plummeting immunisation rates, both through disruption to normal business-as-usual, loss of trust in government services and growing vaccine scepticism, McElnay said.

"Like other countries, we're seeing vaccine hesitancy. That was happening already before Covid, and there are different reasons for that."

The high rates in 2014 and 2015 were the result of a "very focused" effort by everyone, from primary care and the community, hospitals and emergency departments, she said.

"Everyone was behind it because they could see value of vaccination. It was just slow, hard work by many people."

Work at the time showed not everyone coded as 'declines' had fixed views.

"We contacted them all: some were genuinely saying 'I've made my mind up, please don't contact me again'.

"Others said 'I've actually been waiting for the health service to get in touch with me'.

"Sometimes they wanted to wait until their babies were older than six weeks.

"Many times, conversations with those people resulted in them getting their children vaccinated.

"That's how I know they are not all genuine 'declines', it's a mixture."

'Trusted messengers' needed

In the first three months of this year, 79.3 percent of two-year-olds were fully vaccinated, while 8.2 percent 'declined'.

McElnay said when it came to combating vaccine hesitancy, there was no "one size fits all" approach.

"People decline and delay for different reasons, which are deeply personal and specific to their own contexts."

Anti-vaccination messages being spread via social media could only be countered by "trusted messengers", in her experience.

"For some reason people are believing these [online] individuals or getting attached to those messengers that they know nothing about.

"Yet we know that when it comes to making health decisions for your children, both local and international research shows you make those decisions based on information from people in your life that you trust."

Due to the decline in trust in government agencies, the best strategy was to support communities, and Māori and Pacific providers, to build up their skills and opportunities to have those critical conversations about immunisation.

The government's two-year $50 million package to help Māori health providers boost immunisation rates across the life-span, announced in December 2023, was having an impact, McElnay said.

"Sometimes the first encounter doesn't result in vaccination, but we get there in the end."

Different groups had different perceptions about the risk presented by certain diseases, she said.

For instance, parents of young people going off to university were often very worried about meningococcal disease and focused on ensuring their teenagers were vaccinated.

"But they may not feel the same way about measles, for instance."

That variable perception of risk was "driving some of that hesitancy".

"The less you see of a disease, the more likely you are to question whether you need to be vaccinated. But if you've seen a baby with whooping cough, I think you'll make up your mind very quickly that you need your baby to be vaccinated against whooping cough."

Using data to find the gaps

The Aotearoa Immunisation Register was getting "better and better" in terms of producing fine-grained data on what was happening with different age groups and vaccine types.

"It's progressed in leaps and bounds, even in the six months I've been back working with Health NZ.

"That's information we can then feed back to local providers to target any patches of under-coverage, and as time goes by, we will be much better able to analyse that data by vaccine, provider etc."

The childhood immunisation schedule was "the bedrock" of New Zealand's immunisation programme.

While sometimes a measles case popping up could be "a call to arms" and a push for those who may have missed vaccinations to get done, the whole system relied on a systematic rollout.

"We have new babies joining the cohort all the time, the two-year-olds from the end of March will be a different group by the end of October.

"So we need to be focused on childhood immunisations all the time."

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