💉 Why Are There So Many Anti-Vaxxers?
Explaining the reluctance to embrace one of humanity's greatest achievements
Vaccination is a medical marvel. It has virtually eradicated killer diseases like polio and smallpox, and it’s currently helping us manage a pandemic that has wiped out millions of people. For most of us in the developed world, updating our biological immunity is almost as easy as updating our laptop software, but it produces far bigger benefits.
There’s a surprising amount of resistance to vaccines though. Fear of needles and side effects might explain some of this pushback, but much of the hesitance is driven by a lack of trust. Whether it’s motivated by ideology or scientific illiteracy, this lack of trust around vaccine efficacy inevitably translates into unnecessary numbers of dead people.
So why exactly is there so much distrust for one of the most effective medical breakthroughs in human history? And why is it difficult to convince hesitant people that they should trust a particular vaccine, even when belief in the positive value of vaccines is a mainstream position? New research suggests we might be misunderstanding what it means for someone to be undecided or “neutral” on vaccines. Neutral people may not be so neutral after all.
⚖️ How neutral is neutral?
In a 2022 study, researchers at the University of Limerick in Ireland analyzed the “attitude space” of people with varying beliefs about vaccines. They took data from a large survey across 144 countries and almost 150,000 people, looking primarily at questions that asked people how much they trusted vaccines and science.
By comparing how people responded to different questions, the researchers plotted a map showing how much different views correlated with each other. For example, how much are people who trust vaccines also likely to trust science? And when people feel neutral about vaccines, are they more likely to trust or distrust science?
The visual below from the paper shows the attitude map. Each dot represents a particular attitude like feeling high trust or low trust for vaccines. And the colors represent how strong those attitudes are:
Unsurprisingly, dots of the same color sit close together on the map, showing that attitudes tend to cluster. If someone feels strong distrust for vaccines, they’re also likely to have strong distrust for related issues like science. But the researchers highlight a more interesting fact that emerges from the attitude space. In a few crucial ways, the map is not symmetrical:
Strong trust attitudes are more tightly packed together than strong distrust attitudes are. People who strongly trust vaccines are overwhelmingly likely to have strong trust for alternative, similar issues. However, other groups of opinions are more dispersed and don’t correlate so highly.
Strong trust attitudes are fairly isolated. They sit in their own little island distant from everyone else, while other attitudes are more likely to intermingle.
Neutral attitudes do not sit in the middle of the map. Instead, they lean toward the distrust side of the map. People who are neutral about vaccines are more likely to express distrust rather than trust on similar issues.
The problem with this picture is that people are more swayed by others who are similar to them. It’s rare that two extremes get together and change each other’s minds, but influence is stronger when people are less distant to begin with. If people who are neutral about vaccines have more in common with people who distrust vaccines, they’re more likely to move in an anti-vaccine direction than a pro-vaccine direction after an interaction with each perspective.
The researchers simulated these interactions using five popular social influence models. After comparing model outputs across different countries in their dataset, they found a strong link between how isolated pro-vaccine attitudes were within a country and how much trust in vaccines declined in that country after social influence simulations. Countries with more attitude isolation ended up with more anti-vaxxers.
The simulations weren’t merely an academic exercise. Those same countries with high levels of attitude isolation were more likely to show declining vaccination rates over time in real-world data.
In other words, social connection rather than social isolation is what changes minds. The researchers’ simulations suggest that pro-vaccine information campaigns shouldn’t just aim to maximize the extremity of pro-vaccine attitudes; they should also aim to reduce attitude isolation. Shifting neutral people in a slightly more pro-vaccine direction can increase vaccine support without widening the gap between pro-vaccine and anti-vaccine perspectives.
⭐️ Takeaway tips
Bring people together: With the deepening political polarization of social media and news coverage, it may be unrealistic to expect people with diverging opinions to build stronger connections with each other. But this might be our best hope of reducing the attitude isolation that harms public health interventions. We won’t convince anti-vaxxers by getting pro-vaxxers to shout more loudly at them. A better solution comes from leveraging mutual understanding and common interest rather than extreme polarization.
Escape your bubbles: This isn’t the first time I’ve recommended exploring opinions and perspectives you’re unfamiliar with. My point is never to suggest that you should take all ideas seriously - if you find the idea of a flat Earth silly for example, that’s probably because it’s silly. But there are some important and reasonable opinions out there that we’re quick to dismiss without fair exploration. All kinds of political and ethical debates you see in the news today would benefit from each side of the debate working harder to understand each other. And that starts with assuming good intentions and talking to people with an open mind, even when their opinion seems unacceptable to you at first.
Don’t forget 2020: You’re probably living a relatively normal life right now but we were in the middle of a global lockdown just a couple of years ago. If you’re anything like me, you’re quick to take life for granted when it’s going well, and quick to regret not appreciating your good life when it starts going badly. Break this cycle by taking a moment to appreciate everything you love about your life. In the context of COVID-19, we owe much of our current happiness to the efficacy of vaccines.
💡 A final quote
“It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas ... If you are only skeptical, then no new ideas make it through to you ... On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful ideas from the worthless ones.”
~ Carl Sagan
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👋 Until next time,
Erman Misirlisoy, PhD