SCIENCE science.org 17 DECEMBER 2021 • VOL 374 ISSUE 6574 1435
what has happened. Teenagers in some
countries have received three shots; people
elsewhere with a much higher risk of dying
are still waiting for their first.
Millions are alive today because they
got vaccinated, but millions of others have
declined the offer of a safe, free vaccine.
Hundreds of thousands died needlessly.
And any hopes that the vaccines might
curb transmission enough to stop the virus
from spreading have proved ill-founded.
As this year draws to a close, evidence is
mounting that the Omicron variant may
further erode vaccines’ protection. “It is
a little depressing to be here in December
2021 and just still feeling like we have an
uphill battle,” says Natalie Dean, a bio-
statistician at Emory University.
FOR ANY DRUG or vaccine, expectations help
shape whether it is seen as a success. Early
on, scientists worried COVID-19 shots
might only prevent 50% of cases. By that
standard, vaccines vastly overperformed.
But many in the public expected some-
thing like the measles or rubella vaccines,
which offer complete, lifetime protection
from infection—an unrealistic hope. “In
our excitement of having a vaccine and
having one quickly, we forgot that not ev-
eryone in the general public is a vaccino-
logist or virologist,” says Boghuma Titanji,
a virologist at Emory.
Early, hopeful speculation that wide-
spread vaccination would create herd
immunity—when so many people are pro-
tected that the virus has nowhere to go—
compounded the disappointment later.
Herd immunity, always an ambitious goal,
slipped out of reach as the more infectious
Delta variant spread around the world and
the shots’ protection waned.
Overall, the vaccines have proved very
safe. But in the spring, a very rare but po-
tentially deadly clotting disorder emerged
in people who had received vaccines pro-
duced by AstraZeneca and Johnson &
Johnson, which are based on an adeno-
virus vector. Although the risk-benefit ra-
tio was still very good, many rich countries
stopped using the shots once they had al-
ternatives, which damaged confidence in
vectored vaccines elsewhere, especially in
poorer countries that received large ship-
ments of the AstraZeneca vaccine. “The
perception ... has been that Africa was
given subpar vaccines,” says Titanji, who
had to convince her own parents in Camer-
oon to get the shot.
Cynical peddlers of half-truths and lies
about the risks of vaccines and the prom-
ise of unorthodox remedies exploited the
confusion, aided by an information eco-
system that prioritizes “engagement” over
veracity and politicians who would rather
put their voters’ lives at risk than risk ac-
knowledging a complex truth. In the end,
many people felt more comfortable swal-
lowing an unproven drug used to deworm
horses or taking their chance with a deadly
virus than getting a vaccine that had been
shown to protect the vast majority of peo-
ple against severe disease and death.
Nonbiomedical research could have
helped: studies of vaccine hesitancy, the
ways people make medical decisions, and
how misinformation spreads and canbe fought. “That is science, too, and we
do not pay enough attention to it,” Dean
says. Public health agencies neglected to
approach those most vulnerable to mis-
information before they were bombarded
with lies, Titanji says.MANY PEOPLE have not had the luxury of
choosing whether to get the shots. Only 8%
of Africa’s population is fully vaccinated.
“You had this unseemly scramble with the
rich countries paying whatever they could
to get hold of what they wanted, and the
rest pushed to the back of the queue,” says
Helen Clark, co-chair of the Independent
Panel for Pandemic Preparedness and
Response, which was established by the
World Health Organization ( WHO) to draw
lessons from the pandemic.
WHO and other groups in 2020 formed the
COVID-19 Vaccines Global Access (COVAX)
Facility to ensure a more equitable distri-
bution. But its approach—buying vaccines
in bulk and providing them for free to poor
countries—was flawed, Clark says. Rich
countries were happy to donate money
but cornered the market for vaccines, leav-
ing little for COVAX. And the scheme’s
main supplier, the Serum Institute of In-
dia, provided far fewer doses than prom-
ised this year. “We would have been even
worse off without COVAX,” Clark says. But
its modest track record—some 650 mil-
lion doses shipped to low- and middle-
income countries so far—“exposed the limit
of optimism in multilateralism,” says John
Nkengasong, director of the Africa Centres
for Disease Control and Prevention.
Targeting those most at risk across theglobe would not only have been more just,
but also would have averted more deaths,
says Maria Van Kerkhove, a top WHO
epidemiologist. And if rich countries
had fewer doses, they might have fol-
lowed WHO’s advice not to relax public
health measures such as mask wearing
and limits on gatherings, which could
have blunted recent surges. “Particularly
in those countries with access to the vac-
cines, there was a sense that the worst
is over,” says Jeremy Farrar, head of the
Wellcome Trust. That sense also eased the
pressure to ramp up vaccine production
and deliver more doses to more places
fast. As WHO Director-General Tedros
Adhanom Ghebreyesus recently put it:
“In too many countries, the bright light of
vaccines has also become a blinding light
for the continued need to stop this virus
from spreading.”THE PANDEMIC IS RAGING ON. It’s back with
a vengeance in the Northern Hemisphere,
even in countries with high vaccination
coverage. So far, vaccines have held up well
against new variants, from Alpha to Delta.
But the virus’ continuing spread gives it
every opportunity to evolve and find bet-
ter ways around human immunity, as early
data suggest Omicron is doing.
Booster shots have been shown to bol-
ster waning immunity, and may be a way
for rich countries to keep future waves in
check, but low- and middle-income coun-
tries cannot adopt such a strategy “with-
out destroying their health budgets,” says
Gagandeep Kang, a virologist at Christian
Medical College, Vellore, in India. In the
long run, we may need a new generation
of vaccines, says Richard Hatchett, head
of the Coalition for Epidemic Prepared-
ness Innovations. Hatchett says he always
viewed the current arsenal as “rapid re-
sponse vaccines,” fit for the pandemic
emergency, but not for the long-term
struggle with the virus.
One solution may be vaccines that ramp
up the immune response in the mucosa
of the respiratory tract, where the virus
first takes hold. If the approach can curb
transmission, Nkengasong says, “That will
truly become the game changer.” Others
are holding out hope for a pancoronavirus
vaccine that would not only thwart new
variants, but any future cousins of SARS-
CoV-2 as well.
Maybe Science will anoint a new vaccine
as its breakthrough next year, or the year
after. But whatever vaccines the world de-
velops next, we will also have to find ways
to use them better. So far in this pandemic,
it has been the virus, not humanity, that
has done most of the evolving. j“It is a little depressing
to be here in December 2021
and just still feeling like
we have an uphill battle.”
Natalie Dean, Emory UniversityBREAKTHROUGH OF THE YEAR | A TRIUMPH REVISITED 2021