48 Time November 30/December 7, 2020
Health
Vaccines normally Take decades To deVelop
and test, but two COVID-19 shots, from Moderna and
Pfizer (in partnership with BioNTech), have gone from
nonexistent to about 95% effectiveness in 10 months.
Public-health officials and governments now have the dual
challenge of convincing the public that the vaccines are
both safe and scientifically sound, as well as figuring out
how to distribute billions of doses. Here’s what we know
so far about how that’s going.
WHAT TO
KNOW ABOUT
VACCINES
YOUR GUIDE TO WHEN THEY ARE COMING
AND WHAT IT WILL MEAN BY ALICE PARK
WHO
APPROVES
THE VACCINES?
The Food and Drug Admin-
istration must approve any
vaccine. But most COVID-19
vaccine makers won’t initially
apply for normal approval,
which typically requires six
or more months of follow-up
study. Instead, they will likely
ask for emergency-use autho-
rization (EUA), which makes
it possible to release new
drugs and vaccines during
a health emergency. For an
EUA, the FDA has said com-
panies should monitor trial
participants for two months
to make sure the vaccines are
safe and don’t lead to serious
side effects. All of the testing
and other requirements for
evaluating safety and effec-
tiveness remain the same for
an EUA as for full approval.
Many vaccine makers plan to
apply for full approval of their
shots once they accumulate
the appropriate amount of
follow-up data.WERE SHORTCUTS
TAKEN TO DEVELOP
THESE VACCINES?
According to leading public-
health experts and the vaccine
makers, the same rigorous
scientific process that goes
into developing any vaccine
was used to create the
COVID-19 shots. But in some
cases, new technology like the
mRNA-based technique used
by Moderna and Pfizer—the
first two companies to finish
human testing—have sped up
the development process. The
mRNA method doesn’t require
researchers to grow or manip-
ulate SARS-CoV-2, the virus
responsible for COVID-19;
all they need is its genetic
sequence, which Chinese
scientists released in January.
The technology is both fast
and flexible, and allowed vac-
cine makers to develop and
start testing their vaccines in
a matter of months.IF I GET VACCINATED,
DOES THAT MEAN I
CAN’T GET INFECTED?
Not necessarily. But it means
you are less likely to get sick.
When Pfizer announced that
its vaccine was more than
95% effective and Moderna
said its shot was 94.5%
effective, that was how well
they kept people from getting
sick. In the studies, people
were randomly assigned to
get the vaccine or a placebo.
If anyone in either group
felt symptoms of COVID-19
(including fever, cough,
headache and difficulty
breathing), they reported it
to the researchers, who then
decided whether to test for
COVID-19. So the studies
did not test everyone to
see how many people in the
vaccinated group got infected
compared with the placebo
group. Instead, the scientists
took those participants who
tested positive for COVID-19
and compared how many in
the vaccinated group wenton to develop disease and
how many in the placebo
group did. The companies
will continue to test people
in the studies for antibodies
to the COVID-19 virus, which
would include people who
did not show any symptoms
of their infection, so they can
get a better sense of whether
or not the vaccines protect
against not only getting sick
but also against infection.ARE ALL THE
VACCINES MADE
THE SAME WAY?
No. The various companies
are relying on different
technologies. Moderna
and Pfizer use the mRNA
technology based on the
pandemic virus’s genetic
code. The AstraZeneca and
University of Oxford team, as
well as Johnson & Johnson/
Janssen, are relying on
different inactivated cold
viruses loaded with COVID-19