Disinformation about vaccinations has a more dangerous edge on social media. A loose network of activists is in the online trenches, fighting back. Michelle Duff reports.

They couldn't tell me how long they spent at the computer. It was impossible to quantify. Sometimes hours a day. Often well into the night.

The anti pseudo-science activist who goes by the misnomer Skeptical Kiwi wouldn't meet me in person. Their Twitter bio places them in Manawatū, where I also live, but they told me their anonymity means too much to risk even a public flat white. So all I know about Skeptical Kiwi is this; they work in science, or a science-adjacent field. They don't like talking about themselves, and they are one of a growing underground network of disinformation fighters who work to stop lies spreading online.

Some of them are parents. Some of them are scientists. Some of them would be named, and others most definitely would not. But all of them have one thing in common – a personal mission to counter the spread of fake or pseudo-science around vaccines, and a belief that public health entities are not taking the threat seriously enough.

"Misinformation can't go unchecked. Social media gives a voice to everyone who has something to say, regardless of evidence. If enough people spread nonsense, then it only takes a few people to pick it up and problems arise."

What the World Health Organisation categorises as vaccine hesitancy, or the reluctance to get vaccinated despite the availability of vaccines, is not new. When the first vaccine was invented in 1796, for smallpox, people were terrified. What was in the injection? Was it against God's will? Would it result in cow's heads sprouting from their body, as one turn-of-the-century satirist imagined?

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A DELUGE OF MISINFORMATION

"The sentiments haven't changed," says Dr Helen Petousis-Harris, a vaccinologist at the University of Auckland and former head of research at the Immunisation Advisory Centre. "They're still the same, whether it's poisons and toxins, the diseases are not serious or they were going away anyway, or vaccines cause all kinds of idiopathic ills."

The difference now is how the arguments spread, both locally and across borders.

"There's always been the pockets in communities who are against vaccines, but there were limitations on how they could disseminate information. You were restricted to letters to the editor in the paper, letterbox drops, little pamphlets. It was quite limited in terms of reach."

In the 1930s, Whanganui doctor-turned-naturopath Ulric Williams was such an opponent of immunisation, asking: "How do you expect to keep your healthy children by injecting them with the blood of horses?" Even with his restricted circulation his public "immunisation outbursts" did appear to have an impact, with low rates in and around Whanganui. 

Now, a compelling myth can be quickly packaged in whatever format suits – video, gif, meme, blog post, the more shareable, the better – and posted and reposted on Facebook, Twitter, Snapchat and Instagram. It can be accompanied by terrifying images, personal anecdotes, and links to "research".

The power in this misinformation is twofold. It's in its insidious nature – along with being shared by those who truly believe that vaccinations cause harm and actively campaign against them, it's passed along by the well-meaning masses; mums, aunties, grandfathers. And it's in the speed and sheer volume; there's barely time to debunk one story before it mutates and folds into another. 

"We used to deal with a new myth or a new piece of misinformation once or twice a year, where you'd look at it and refute it and you'd develop something to help people understand where it had gone wrong," Petousis-Harris says. "For example, there might be a book written by the anti-vaccine lobby, so you'd develop a refutation to the material. 

"Those were periodical. Now you can have a new thing every week, every day. There's nothing new in it, it's just that it's a deluge of misinformation."

WE THOUGHT WE WERE WINNING

Vaccination rates in New Zealand weren't reliably known until 2005, when the National Immunisation Register was established. Before then, you'd only know if you'd been vaccinated by taking a look at your Plunket book, or doctor's records if they were available.

Back then, rates were about 70 per cent, and by addressing "systems" issues – tracking who needed to be immunised, establishing outreach programmes, beginning active promotion – numbers began to trend upwards.

By 2015, the national target of 95 per cent of all eight-month-olds receiving their first three immunisations on time didn't look out of reach – even though there was still low coverage in pockets of the country, coverage levels were around 94 per cent overall, and 91 for Māori.

"I think a lot of people thought 'We're sorted, we've got this'," says Petousis-Harris. "I think there was this idea among a lot of people that we'd solved the problems. But you don't need to spend much time in social media land to know that you haven't, and that you've got a real active movement. 

"We had a honeymoon for a while, and then this stuff started to seep out of the cracks and the circulation of this material sort of exploded globally. Vaxxed [the movie] was a real catalyst. It gave the movement a real global presence, and it gave people something to belong to."

Does she think it has affected confidence in vaccines? "I think so, yes. That's definitely part of it. You've got access and poverty barriers, and then you've got this. It's a global problem. 

"This disinformation has now permeated out of those wealthier networks who circulate the anti-vaccine material and their social media has gained access to those high-deprivation people. 

"In places like Northland they are now struggling with this type of material in their really highly deprived population, and there have been massive declines up there. Massive. 

"They lag behind in terms of coverage anyway, so now they're really taking a hammering."

Petousis-Harris's own work debunking pseudo-science over decades has come at a personal cost. "I've had my life threatened, I've been threatened with legal action, I've been OIA'd [had to comply with Official Information Act requests] multiple times, had complaints made to my workplace. They don't play by the same rules."

But in some places where anti-vaccination campaigners are active, like in Northland, public health authorities have found social media can also work in their favour. 

At times of an outbreak, such as when meningococcal W hit the region last year – resulting in three deaths – Northland District Health Board communications manager Liz Inch found herself answering dozens of Facebook messages late into the night. She was able to instantly answer safety questions and tell people how to get vaccinated. 

Northern DHB's Facebook page is more active than most, with almost 10,000 followers (Auckland, more than twice its size population-wise, has close to 8000 followers). And Inch says the community, most of whom do vaccinate, are quick to alert them to anti-vaccination propaganda circulating. In February, this included claims spread on social media that Kaitaia College students were being "mass-vaccinated" without parental consent.

It was a mobile clinic set up to respond to the outbreak, with consent forms required.

VAX WARS

With the rise of the wellness industry and the promotion of natural, back-to-basics lifestyles – think fresh-faced Instagrammers and celebrity paleo-diet proponents – pseudo-science claims online are not hard to find. In today's image-oriented world, the impact of bloggers and social media "influencers" can't be underestimated.

Earlier this year, Instagram celebrity and blogger Taylor Winterstein, the wife of Australian NRL star Frank Winterstein, announced appearances in New Zealand and Samoa in June for her "Tay's Way: Making Informed Choices" workshop. Winterstein, who has 21,000 followers on Instagram, promotes herself as "motivating the next generation of parents to TAKE BACK CONTROL". Tickets to her event cost $200.

In Dunedin, science graduate and functions assistant Melissa Taane, 29, read the news stories with increasing anger. "People like Taylor Winterstein make a lot of money out of running these workshops that are aimed at mothers. She is a charlatan, and stopping people like her sharing that anti-vax information would go quite a long way." 

Taane began a petition on Change.org to stop Winterstein's tour, calling for her to be de-platformed. "Allowing non-medical professionals to spout their ignorance and fear-mongering against vaccinations for their own financial gains, should not be something we encourage or tolerate," she wrote.

The workshops weren't welcome in Samoa either. Ministry of Health chief executive Dr Take Naseri told the Samoa Observer they were a "public health threat", and that one serious virus could "wipe out this population in less than two weeks". Taane's petition gained more than 8000 signatures before Winterstein announced in May she would be cancelling her tour. 

"I'm just very pro-science," says Taane, who also spends hours of her own time online engaging in debate with anti-vaxxers. "Vaccination is so important because it affects everybody, it's not a personal decision that affects just you.

"I think there's a need to fight back against that voice, because a lot of them are very vocal so they can seem more prevalent than they really are."