March 2021, ScientificAmerican.com 23THE SCIENCE
OF HEALTHClaudia Wallis is an award-winning science journalist
whose work has appeared in the New York Times, Time,
Fortune and the New Republic. She was science editor
at Time and managing editor of Scientific American Mind.Illustration by Fatinha Ramos
Like billions of people around the world, I am eagerly awaiting
my turn for a COVID vaccine. But not everyone shares my enthu-
siasm. My sister-in-law, an alternative health practitioner, says
she doesn’t trust “Big Pharma” to have formulated safe shots. She
prefers to fortify her immune system with supplements and a
healthy lifestyle. “I avoid all vaccines,” she told me.
She is not alone. By now the term “vaccine hesitancy” has
entered everyday pandemic discourse, joining “flatten the curve”
and “social distancing.” Polls in December 2020 suggested that
about 30 percent of Americans harbor doubts about COVID vac-
cinations. If that number holds steady, unvaccinated people could
form a deadly reservoir of the SARS-CoV-2 virus, able to restart out-
breaks. We need a level of protection known as herd immunity,
which experts estimate will require between 60 and 90 percent
of the population to be vaccinated or have antibodies resulting
from infection.
Vaccine reluctance looms large among certain
subgroups: 42 percent of Republicans, 35 percent of
Black adults and 33 percent of essential workers, for
varying reasons, said they would probably or definitely
refuse the vaccine in a December poll conduct-
ed by the Kaiser Family Foundation (KFF).
Experts say efforts to overcome hesitancy
should address specific concerns from these
groups and include transparency
about vaccine benefits and risks.
Here are seven key ideas:
- It’s not necessary to
change the minds of com-
mitted anti-vaxxers; they
are just a tiny slice of
the population, and we
can reach herd immunity
without them. Consider,
for ex ample, that in the 2018–
2019 school year, only 2.5 per-
cent of U.S. kindergartners were
exempted from vaccination. “We
are more interested in people who
might be ambivalent,” says Rupali
Limaye, a health communication scientist at the Johns Hopkins
Bloomberg School of Public Health.- Facts alone will not persuade skeptics. A 2014 study of adults
who worried that vaccination might cause autism—a debunked
idea—found that corrective facts had no impact on their inten-
tions to vaccinate a child. The information actually hardened
negative views among those most opposed. “A more convincing
approach is to address the lack of trust or reach people with
trusted messengers rather than trying to throw facts and sci-
ence at people,” says Brendan Nyhan, lead author of that study
and a professor of government at Dartmouth College. - Some minority groups, such as Black and Native Americans,
have strong historical reasons to view health authorities with
suspicion. Experts favor working closely with civic and faith
leaders, admired athletes and other trusted figures within those
groups. This technique was first developed to promote practic-
es that prevent HIV/AIDS among gay men and has since been
adapted for other purposes and populations. - Low levels of vaccination, particularly among low-income
communities, often reflect practical barriers. Offering extend-
ed hours for immunizations and ensuring that the public
knows there is no cost are two ways to improve the rates,
says Samantha Artiga, director of racial equity and health pol-
icy at KFF. - Talk about how popular the vaccine is. “It might be tempt-
ing to say, ‘Get your vaccine because half of Americans won’t,’”
says Katy Milkman, a behavioral scientist at the Uni-
versity of Pennsylvania, but that “emphasizes how
common it is to decline the vaccine.” Research on vot-
ing turnout shows it is more effective to say everyone
is doing it, she notes: “People follow perceived norms.” - Overcome the human tendency to procrastinate. A 2009
study at Rutgers University showed that people who
were given an opt-out appointment for a flu shot
were 36 percent more likely to be vaccinated
than folks who were sent a link to
schedule it themselves. Once the
new vaccines are widely available,
Limaye suggests health providers
can say to patients who come in
for other, more routine rea-
sons, “Let’s go ahead and
get that COVID shot.” - For forgetful types,
simple reminders—by
text or voice message—can be
powerful. A 2019 study showed that
frequent daily reminders to com-
plete drug treatment for tuberculo-
sis greatly im proved outcomes. “You’d
think that would be irritating, but it was
effective,” Milkman says. So when it
comes time for that second COVID vaccine
dose, she suggests, “Let’s nag people.”
7 Ways to Tackle
COVID Vaccine
Hesitancy
Use trusted messengers, remove
barriers, and other research lessons
By Claudia Wallis