Affective risk aversion and Covid vaccine denial

After several unsuccessful attempts in the confused and governor-hobbled Florida vaccine roll-out, my spouse and I were recently able to get the first of two Moderna jabs. Despite the tragic (and up to 40% unnecessary) loss of life and the trashing that our economy has suffered because of the coronavirus over the last year, the number of people who are refusing, or plan to refuse, this vaccination is astoundingly high. Some surveys show this denial in over 30% of the population.

What is going on here? What is the thinking of people, especially healthcare workers, who refuse this critical piece of the amazing international science-based effort to defeat the virus? My take is that much of this denial can be pegged to a deeply evolutionary “brain misfire” called affective risk aversion, where an emotion-influenced part of our brain too-often wins out over the more rational math-evaluator part of our thinking.

What is affective risk aversion?

I do not ride rollercoasters anymore. Despite my long experience in analyzing quantitative risk, it is the affective risk aversion, which is my gut screaming, “Don’t be a fool!” that keeps me off that ride.

Humans appear to have separately evolved at least two brain/body systems for evaluating the risks threatening our survival, and they often give us different answers to important threats. In the case of the coronavirus and its several new preventative vaccines, the gut-friendly bet of not getting the vaccine multiplies your quantitative risk of substantial harm or death from Covid by at least 1000 times.

University of Oregon psychology professor Paul Slovik has long studied the various sociological and psychological factors that affect people’s perceptions of risk. All of us are subject to ranking many of life’s threats “incorrectly” as compared with a rational, quantitative assessment of actual risk. Sometimes this response just keeps us off rollercoasters. Sometimes the choice is deadly.

Affective risk aversion is the combination of factors that causes our brains to evaluate risks facing us, like my rollercoaster ride, as feeling, rather than as establishable fact. Slovik’s theory of this parallel evolution of risk evaluation resembles in several ways the “Thinking Fast and Slow” brain model that won Daniel Kahneman the Nobel Prize in economics in 2011 and produced a best-selling book by the same name.

In Kahneman’s model, humans and our forebear species first evolved ways to adjudge life-threatening risks in a “gut-level” decision-action mode that is very fast, but relatively inaccurate and prone to error. And, yes, sometimes literally in our intestinal system, which likely evolved “decision-making” chemical signals to the rest of the body well before brains appeared in the evolutionary scale. Better to think incorrectly that the vague movement in the savanna grass is a lion lurking to strike, and quickly get out of the way, than to be more curious and find out the hard way that it indeed was a lion lying in wait.

A separate, cognitive region of the brain, in Kahneman’s model, later developed a “thinking slow” mode that we call rationality, which often gives us more accurate and long-term solutions, but may take its time to get us there. Our “thinking fast” mode finds ways to get us quick nourishment, for instance, while our “thinking slow” mode causes us to slow down and develop a long-term survival food strategy.

In one of his risk assessment studies, Paul Slovik found that people often overestimate common risks, like nuclear power, based more on affective reactions, while at the same time underestimating the well-documented quantitative and more likely risks of driving a car, an activity that seems “natural” to many of us.

The news media and Covid vaccine deaths

We have become almost inured to coronavirus deaths in the United States, despite some days that have exceeded over 4000 deaths, and with us approaching the half-million mark of total fatalities. We are finally starting to see a decline in hospital admissions for Covid-related illnesses, which not long ago topped over 100,000 Americans per day and still approach 80,000 on any given day. In one study recently published in the Lancet, three-quarters of hospitalized Covid patients continued to have symptoms six months later, with half still showing chest abnormalities under x-ray. Covid remains a dangerous health threat, but much of the country remains oblivious until it happens to someone close to them.

At the same time, a lot of press coverage has been given to a small handful of “Covid-adjacent” deaths after a vaccine injection, even though no cause-effect link has been established. This is out of over 44 million vaccinations administered so far in the U.S. Any rational analysis demonstrates that the risk of long-term injury or death from Covid exceeds the risk of the Covid vaccination by many thousands of times. This is true for virtually all other vaccines as well, but rationality and data do not stop the vaccine denial movement.

Let us be clear. That gut-level fear that many people have of any medical injection is very real. One experienced medical worker who passed out after getting her vaccine injection recounted how this happens to her with every injection. Affective risk aversion to this vaccine can have very real body effects, but not necessarily to the vaccine itself.

Many people will also experience a vaccine reaction similar to an annual influenza injection, with a sore arm and even a fever for a couple of days. This is the vaccine working, preparing your body to successfully withstand a dose of the real virus. In a rational world, our “thinking slow” brain overrules our affective aversion to needles, and we thrive by our good decisions.

Conspiracies and affective thinking

But we often do not live in a rational world. Let me be frank. If you think that vaccines in general are more unsafe than the diseases they prevent, you have been grabbed by conspiratorial thinking that preys on your non-rational fears. You are making a very bad life choice.

I could go down a list of conspiracies that have possessed millions of Americans in recent months. Almost all of them have this factor in common. They take a very-low-probability fear, but one with a very high affective response, and blow it up so much that human rationality goes right out the window. If you are a real estate agent from Texas and you found yourself breaking into the U. S. Capitol to stop some imagined “steal” of an election, then you, too, have been fooled by both your gut/brain chemicals and corrupt, opportunistic politicians preying on your fears.

The same goes for your coronavirus vaccine fears. Get your Covid vaccine as soon as it is offered to you. But keep doing the rational mitigations as well, like wearing a mask and social distancing. You are no longer a worm without a rational brain. Act like it.


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