Some COVID-19 mutations may dampen vaccine
By Marilynn Marchione
The Associated Press
January 23, 2021
Scientists are reporting troubling signs that some recent
mutations of the virus that causes COVID-19 may modestly curb
the effectiveness of two current vaccines, although they stress
the shots still protect against the disease.
Researchers have expressed concern about the preliminary
findings, in large part because they suggest that future
mutations could undermine vaccines. The research tested
coronaviruses from the United Kingdom, South Africa, and Brazil,
and was led by Rockefeller University in New York with
scientists from the National Institutes of Health and elsewhere.
A different, more limited study out Wednesday gave
encouraging news about one vaccine’s protection against some of
One way vaccines work is to prompt the immune system to make
antibodies that block the virus from infecting cells. The
Rockefeller researchers got blood samples from 20 people who had
received either the Moderna or Pfizer vaccine and tested their
antibodies against various virus mutations in the lab.
With some, the antibodies didn’t work as well against the
virus — activity was one-to-threefold less, depending on the
mutation, said the study leader, Rockefeller’s Dr. Michel
"It’s a small difference but it is definitely a difference,"
he said. The antibody response is "not as good" at blocking the
Earlier research established that the two vaccines are about
95% effective in preventing COVID-19 illness.
The latest findings were posted late Tuesday on an online
website for researchers, <https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1>,
and have not yet been published in a journal or reviewed by
other scientists. Nussenzweig is paid by the Howard Hughes
Medical Institute, which also supports science coverage at The
Associated Press. The university has applied for a patent
related to his work.
The coronavirus has been growing more genetically diverse,
and scientists say the high rate of new cases is the main
reason. Each new infection gives the virus a chance to mutate as
it makes copies of itself.
Recent variants, or versions of the virus, that emerged in
the U.K., South Africa, and Brazil seem to spread more easily
and scientists say that will lead to more cases, deaths, and
hospitalizations. The new variants do not seem to cause more
serious disease, but their ability to eventually undercut
vaccines is a concern.
E. John Wherry, an immunology expert at the University of
Pennsylvania, said the Rockefeller scientists are "among the
very best in the world" at this work and their results are
"We don’t want people thinking that the current vaccine is
already outdated. That’s absolutely not true," he said. "There’s
still immunity here ... a good level of protection," but the
mutations "do in fact reduce how well our immune response is
recognizing the virus."
The news comes at "a really important time in the pandemic,"
said Dr. Buddy Creech, a vaccine specialist at Vanderbilt
"We’ve got an arms race between the vaccines and the virus.
The slower we roll out vaccine around the world, the more
opportunities we give this virus to escape" and develop
mutations, he said.
Dr. Matthew Woodruff, an immunology researcher at Emory
"This is going to be kind of a slow walk of evolution. We’re
going to have to have tools that slowly develop with it," such
as treatments that offer combinations of antibodies rather than
one, he said.
Dr. Drew Weissman, a University of Pennsylvania scientist
whose work helped lead to the Moderna and Pfizer vaccines, said
the antibody findings are worrisome, but noted that vaccines
also protect in other ways, such as spurring responses from
other parts of the immune system. The new work involved only 20
people and not a huge range of ages or races, "and all of that
matters" in how generalizable the results are, he said.
On Wednesday, Pfizer and its German partner BioNTech reported
a second round of reassuring findings about its vaccine against
one of the variants.
Earlier this month, Pfizer and researchers at the University
of Texas Medical Branch said that the vaccine remained effective
against a mutation called N501Y from new variants found in the
U.K. and South Africa. Likewise, there was no sign of trouble
when they tested some additional mutations.
The latest work tested all the mutations from the variant
from the U.K. at once rather than one-by-one. Tests from 16
vaccine recipients showed no big difference in the ability of
antibodies to block the virus, the researchers said in a report,
Pfizer didn’t immediately comment about the Rockefeller
findings, but its chief scientific officer, Dr. Philip
Dormitzer, previously said next steps include testing the
vaccine against additional mutations found in the variant from
Moderna and AstraZeneca, which makes a different type of
COVID-19 vaccine used in some countries, also have been testing
how their vaccines hold up against different mutations.
If the virus eventually mutates enough that the vaccine needs
adjusting — much like flu shots are altered most years —
tweaking the recipe wouldn’t be difficult for vaccines made with
newer technologies. Both the Pfizer and Moderna vaccines are
made with a piece of the virus genetic code that is simple to
It’s "wishful thinking" to believe that first-generation
vaccines will be enough, or that vaccines alone will solve our
problems, said Mayo Clinic vaccine expert Dr. Gregory Poland.
"We are shooting ourselves in the foot by allowing
unmitigated transmission of this virus" and not doing "common
sense" measures such as mandating mask-wearing as some other
countries are doing, he said.
"How can the bars and restaurants be full? It’s like ‘what
pandemic?’ We’ve reaped the seeds we’ve sown," he said.
Medical writer Lauran Neergaard contributed reporting.
The Associated Press Health and Science Department receives
support from the Howard Hughes Medical Institute’s Department of
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