COVID Omicron Variant May Have “Significant” Capability To Evade Vaccine Protection – Even From Third Dose
By TAYLOR & FRANCIS GROUP
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| Vaccines and previous infection could offer some “stronger than basic” protection to Omicron, early study suggests. |
Tube samples of Omicron, however, do further propose its “significant” capability to evade protection from previous infection and, potentially, even third vaccine dose.
Published December 11, 2021, one of the earliest, peer-reviewed studies looking into
the Omicron variant of COVID-19 suggests
that people previously infected with COVID, and those vaccinated, will have
some, “stronger than basic” defense against this new strain of concern.
However, the test tube
(or ‘in-vitro’, scientifically) samples of Omicron examined in this new
research do show it “exceeds” all other variants in its potential capability to
evade the protection gained from previous infection or vaccination.
Published in Emerging Microbes & Infection, the findings also suggest that although a third-dose enhancement strategy can “significantly boost immunity,” the protection from Omicron “may be compromised” – but more research is needed to better understand this.
Reporting on this very
early study, lead author Youchun Wang, Senior Research Fellow from the National
Institutes for Food and Drug Control in China, says their results support
recent findings in South Africa which highlight Omicron was “easy to evade
immunity.”
“We found the large
number of mutations of the Omicron variant did cause significant changes of
neutralization sensitivity against people who had already had COVID,” Wang
says.
“However, the average
ED50 (protection level) against Omicron is still higher than the baseline,
which indicated there is still some protection effect can be observed.”
Wang, who is Former
Chairman of the Medical Virology and Vice Chairman of the Medical Microbiology
and Immunology of the Chinese Medical Association, does adds caution though.
He says that because the
antibody protection – in the form of previous infection or vaccination –
decreases gradually over a period of six months, Omicron “may be able to escape
immunity even better.”
Plus, his team’s paper
predicts that whilst “a third-dose enhancement strategy can significantly boost
immunity,” the “protection from Omicron may be compromised.”
The expert team of 11
scientists looked at 28 serum samples from patients recovering from the
original strain of SARS-CoV-2. They tested these against
in-vitro Omicron samples, as well as four other strains marked ‘of concern’ by
the World Health Organization (such as Delta), and two variants marked as ‘of
interest’.
“This study verifies the
enhanced immune escape of Omicron variant, which sounds the alarm to the world
and has important implications for the public health planning and the
development of matching strategies,” Wang summarizes.
Now, the team states
that more research, carried out not just in-vitro but in real-world studies is
urgently needed to better understand Omicron. And, specifically, whether it can
“escape from the vaccine-elicited immunity to cause more severe disease and
death.”
“It needs to be
re-evaluated whether the antibodies can still be effective against the Omicron
variant,” the authors state.
“The exact impact to
human protection may be influenced by more factors such as the infectivity of
Omicron variant relative to other variants to human populations and the viral
fitness of Omicron once the humans are infected.
“More population studies
including the level of immune protection and symptoms among people infected
with Omicron are needed to fully establish the global impact of Omicron to the
control of COVID-19 pandemic.”
The major caveat of this
study is that it is in-vitro in nature and that it used pseudotyped
(manufactured) viruses. However, previous studies have used in-virto as an
established measure of “good correlation” and the current vaccine literature
“has established that the in vitro neutralization assays are good predictors of
vaccine protection efficacy and real-world vaccine effectiveness.”
Therefore, the authors
state, their data “may well predict the potential reduction of vaccine
protection against the new Omicron variant.”
Reference: “The
significant immune escape of pseudotyped SARS-CoV-2 Variant Omicron” 11
December 2021, Emerging Microbes & Infections.
DOI: 10.1080/22221751.2021.2017757
