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Escaping COVID-19 Vaccine Hesitancy

There are emotional and intellectual reasons people give for their vaccine hesitancy. Addressing them can help these people off the fence.

As I write this, 4.8 billion doses of a COVID-19 vaccine have been administered globally. Even with my scientific background, I cannot easily wrap my head around this number, 4.8 billion. If you think of each syringe carrying a dose as a pencil, and you put these 4.8 billion pencils side by side like they are in a colouring box, you end up with a line that is almost twice the length of the Earth’s diameter. Dig down the Earth, go through the core, emerge at the other side and come back, and you have an idea of the size of this thing.

Despite the wide use of these vaccines, their proper testing in clinical trials, and their clear effectiveness in the real world (and the absence of massive deaths from the vaccine in the elderly that some anti-vaxxers predicted), a small percentage of people admit they could be persuaded to get the vaccine but would rather not. There is no simple portrait of who these people are; it’s a somewhat diverse group that arrives at hesitancy for reasons that can be sorted into five categories. There is confidence, meaning trusting (or not) the people involved in the development, authorization and manufacturing of the vaccines. Some people’s trust in governments and in pharmaceutical companies has been eroded to the point of paralyzing doubt. There is complacency: downplaying the risks of contracting the disease and not seeing the benefits of the vaccine. Many people face constraints to getting vaccinated, whether it’s a fear of needles or the lack of time to go get vaccinated and ride out the potential temporary side effects. Add to this list calculation, which is the thought process that leads you to decide if the vaccine is right for you or not, and collective responsibility, and we have the 5C model which describes the psychology at play.

Some of the factors driving vaccine hesitancy are very primal and instinctual, while others play on our desire to find a rational, scientific-sounding justification for our decision. Let’s explore both.

The fear of what might happen

I will admit: it is easy for a worry about what might happen to roll down a mental hill and grow in size, like a snowball, until our imagined risks are all we can see. This is especially true of things we put inside our body. Food, for example, can be a very polarizing topic, and modern diets have often been compared to religions. It speaks to our primal desire for purity, and vaccines can tap into the same vein. There is also a perceived loss of control: what happens once this vaccine is inside my body?

In a recent survey of Quebec adults not yet vaccinated against COVID-19, the number one reason given for refusing or delaying the vaccine was the fear of potential side effects. Indeed, a refrain on social media commonly heard from both anti-vaccine activists and individuals who are on the fence about receiving the vaccine is that “we don’t know what the long-term effects of this vaccine are going to be.” Could the vaccine give us cancer? Could it affect fertility? Could it make us sprout a third arm?

The good news is that our long history of developing and administering vaccines has shown that, when delayed effects have happened, it was always within eight weeks of receiving the vaccine. Moreover, and with the exception of cases of narcolepsy associated with the H1N1 influenza vaccine (where the causal link is still contentious), the side effects from the vaccines were of the same sort that could be caused by the infection itself. So if we worry about the vaccine, we should also worry about the disease.

In the case of the RNA-based COVID-19 vaccines, that RNA molecule breaks down fairly quickly in the muscle cells that get injected with it, and this RNA stops being used as a recipe to make the spike protein within about a week. Despite all the scaremongering from people deeply opposed to any sort of vaccine, there is no evidence these vaccines impact the fertility of men or women (whether it’s ovarian function, placental function or the ability to have kids) and no reason why they would. Just because we can conjure up a risk does not mean it is scientifically plausible.

Also, the hypothesis that these vaccines might create “immune enhancement” and make the disease worse in vaccinated people who do come across the virus “never materialized,” said Dr. Peter Hotez, the dean of Baylor College of Medicine’s National School of Tropical Medicine and the co-director of the Texas Children’s Hospital Center for Vaccine Development. As for the viral claim that COVID-19 vaccines prevent three deaths but also inflict two, it came from a paper which was retracted last July. It committed the cardinal sin of assuming that any death following vaccination was due to the vaccine, a fallacious argument we see in the related “VAERS scare,” where anti-vaxxers plunder a legitimate government database and assume, wrongly, that anything reported in it can be directly attributed to the vaccines. Imagine if a similar database existed where people could submit reports of anything bad that happened to them after using their cell phone. Everything from diarrhea to skin rashes to heart attacks would get blamed on cell phone usage. Clearly, that’s not how causation works.

All of this apprehension is in the social media water and it affects some people more than others. There is a great quote in a recent Maclean’s article on vaccine hesitancy: “I’m just anxious. I get anxious about new things.” Sometimes, it’s as simple as that, and empathetic conversations can help.

Vaccines are not antibiotics

Others may be swayed into hesitancy by a more, shall we say, intellectual argument. The Internet is still haunted by the ghost of Dr. Geert Vanden Bossche’s open letter to the World Health Organization, in which he predicted “disastrous consequences for global health” because of the COVID-19 vaccines. His claim is that vaccinating people in the middle of a pandemic would put some sort of selective pressure on the virus to develop mutations that would evade vaccine-acquired immunity. He worries the vaccines will turn the coronavirus into “a wild monster,” and his worry has infected some people. Can the vaccines act in this manner?

Dr. Anne Gatignol, a professor of molecular biology and virology at McGill’s own Department of Medicine and Microbiology & Immunology, told me she was not aware of any historical precedent for this. “It has not occurred for smallpox (the only eradicated virus),” she wrote to me, “polio or measles (the closest on their way to eradication).” Mutations that occur in the coronavirus’ genetic material are due to chance. When copies of the virus are made inside our bodies, the enzyme that replicates the genetic material sometimes makes mistakes, also known as mutations. These random mutations, like a typo in a quickly typed email, can make no difference to the virus, or they may be disadvantageous, or in some cases they may prove advantageous to its transmission. But the more bodies the coronavirus gets to replicate in, the more chances it has to mutate and to potentially become a problematic variant.

And being vaccinated helps prevent this. In fact, every SARS-CoV-2 variant of concern on the radar of public health agencies—from alpha, discovered in the UK in September 2020, to lambda, first seen in Peru in December 2020—emerged before mass vaccination started or in populations where vaccination had just begun and where most people were unvaccinated. The delta variant, which is highly transmissible and which is creating a second pandemic especially for the unvaccinated, was first seen in India in October of last year. India’s population started being vaccinated on January 16, 2021. The vaccines did not create these variants. Even strains of the virus that are being monitored because we’re not yet sure if they might behave differently all appeared by January 2021.

Yet, you might think this idea of vaccines putting selective pressure on the virus makes sense because of an often-used analogy: it’s just like overusing antibiotics and the emergence of antibiotic-resistant bacteria, we are told. Makes sense, right? Except, as Dr. Gatignol explained to me, the two are not comparable. “Antibiotics are treatments, not vaccines. Bacteria do not resist antibiotics by mutations but by the acquisition of mobile genetic elements harbouring resistance genes.” These mobile elements already exist: they are made by other bacteria or fungi in the environment. The bacteria that do have them survive the antibiotic and grow.

But if we still worry about a theoretical pressure on the virus because of the vaccines, we have to remember that no mutation that arises in the virus evades the vaccine itself; the mutation can evade our immunity. “Even if we stopped vaccinations,” Dr. Emma Hodcroft, a molecular epidemiologist at the University of Bern, wrote to me, “we would continue to have many, many infections (and many hospitalizations and deaths) which would give survivors immunity. This could then pressure the virus to evade immunity.” Whether we vaccinate or not, the potential for dangerous variants exists, but in the scenario in which we do vaccinate, the morbidity and mortality burden is much, much, much lower.

And all this talk of mutations evading our vaccine-acquired immunity presumes that this immunity is only made up of antibodies recognizing the spike protein. Change the spike protein enough, and antibodies can’t see it anymore. “But immunity by antibodies,” Dr. Gatignol reminded me, “is not the sole immunity; cellular immunity develops as well.” Professor Timothy Sheahan, a virologist at the Gillings School of Global Public Health at UNC Chapel Hill, agrees. “You have more than antibodies,” he told me. “You have T cells. T cells typically are not targeting Spike and proteins that are external to the virus particle. They might target less plastic enzymes [meaning enzymes that don’t mutate or change shape as much] that the virus needs to replicate.” Those enzymes are highly conserved and are unlikely to mutate if they are to keep doing their job, which is to help the virus make more copies of itself.

The bottom line is that vaccines are the best way we have to prevent transmission of the virus, hospitalizations, deaths and, yes, to slow down the emergence of variants. “Stopping vaccination because of a theory about what might happen in the future,” Dr. Sheahan told me, “doesn’t help me today. The world is on fire.” If the virus’ genetic material ends up drifting in a way that makes our current crop of vaccines significantly less effective, there is always the possibility of boosters tailored to these new variants. After all, we already do this yearly for influenza.

Whether the argument is an emotional anxiety for what might happen or an intellectual rationalization for why the vaccine is a bad idea, the resulting hesitancy is driving this relatively small group of people down an unnecessarily harrowing path. As local writer Toula Drimonis recently summarized, 95% of Quebecers who were diagnosed with COVID-19 and 95% of those who were hospitalized because of the disease between June 27 and July 3 of this year were not fully vaccinated, with similar numbers out of Alberta. The 11 COVID patients who had to be taken to the intensive care unit in Montreal and Laval recently were also not adequately vaccinated.

What is standing between the vaccine hesitant and their potential protection from COVID-19 is often nothing more than the human brain: susceptible to anxiety, seduced by misinformation, vulnerable to doubt. The virus itself, brainless but injurious, has no such qualms.

Take-home message:
-We can think of the psychology at play in vaccine hesitancy as the 5C: confidence, constraints, complacency, calculation and collective responsibility
-Some people worry about the potential long-term side effects of a COVID-19 vaccine, but in the history of vaccination, when delayed effects have been seen, it was always within eight weeks of receiving the vaccine
-The claim that vaccines will put selective pressure on the coronavirus and turn it into a “wild monster” is not borne out by the science.


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